To see the other types of publications on this topic, follow the link: Pier.
Journal articles on the topic 'Pier'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Pier.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Sang, Liansheng, Jun Wang, Tiejie Cheng, Zhixing Hou, and Jueyi Sui. "Local Scour around Tandem Double Piers under an Ice Cover." Water 14, no. 7 (April 6, 2022): 1168. http://dx.doi.org/10.3390/w14071168.
Full textAbstract:
Compared to the scour around a single pier, the local scour process around tandem double piers is much more complicated. Based on laboratory experiments in a flume, we conducted the scour process around tandem double piers under an ice-covered flow condition. The results showed that when the pier spacing ratio L/D = 2 (where L = the pier spacing distance, and D = the pier diameter), the rear pier (the downstream one) will intensify the horseshoe vortex process behind the front pier, and the scour depth around the front pier will increase by about 10%. As the pier spacing ratio L/D increases, the scour depth around the front pier will gradually decrease. When the pier spacing ratio L/D = 5, sediment scoured around the front pier begins to deposit between these two piers. To initiate a deposition dune between piers, the pier spacing distance under an ice-covered condition is about 20% more than that under an open flow condition. The results also showed that the existence of the rear pier will lead to an increase in the length of the scour hole but a decrease in the depth of the scour hole around the front pier. The local scour around the front pier interacts with the local scour of the rear pier. The maximum scour depth of the scour hole around the rear pier increases first, then decreases and increases again afterward. When the pier spacing ratio L/D = 9, the scour depth around the rear pier is the least. With an increase in the pier spacing ratio, the influence of the local scour around the front pier on the local scour around the rear pier gradually decreases. When the pier spacing ratio L/D is more than 17, the scour around the front pier has hardly any influence on that around the rear pier. The scour depth around the rear pier is about 90% of that around the front pier.
2
Štimac Grandić, Ivana, and Davor Grandić. "Reduction in wind force in relation to corner design of bridge piers." Engineering review 40, no. 2 (April 1, 2020): 88–100. http://dx.doi.org/10.30765/er.40.2.10.
Full textAbstract:
The effects of wind on beam bridges can be significantly reduced with careful design of deck, roadway and wind barriers, as well as with appropriate design of piers. In this paper, the influence of corner design of rectangular cross-sectional piers to total wind force on piers is investigated. The total wind force changes, due to a different corner design of rectangular cross section of piers in free standing phase, are analyzed for piers of different heights, different environments and different wind velocities. The correlation between changes in total wind force and changes in geometric properties of a pier is also shown. By rounding the corners of a pier square cross section, the total wind force on pier in free standing phase can be drastically reduced in comparison to the total wind force on sharp corner pier with a small reduction in a load bearing properties of the pier. Changes in the bridge pier environment, as well as changes in pier height and wind velocity have negligible influence on changes in reduction of total wind force due to rounding the pier corners.
3
Hassan, Zahraa F., Ibtisam R. Karim, and Abdul-Hassan K. Al-Shukur. "Effect of Interaction between Bridge Piers on Local Scouring in Cohesive Soils." Civil Engineering Journal 6, no. 4 (April 1, 2020): 659–69. http://dx.doi.org/10.28991/cej-2020-03091498.
Full textAbstract:
Local scour at the piers is one of the main reasons of bridge foundation undermining. Earlier research studies focused mainly on the scour at a single bridge pier; nevertheless, modern designs of the bridges comprise wide-span and thus group of piers rather than a single pier are usually used to support the superstructure. The flow and scour pattern around group of piers is different from the case of a single pier due to the interaction effect. Reviewing the literature of local scour around bridge piers group revealed that the local scour around bridge piers group founded in cohesive soil bed was not investigated, and most of the scour studies were related to scour in cohesionless soils. The objective of the present study is to investigate the effect of the interaction between two in-line (tandem) circular bridge piers of variable spacings founded in cohesive soil on the local scour. A set of laboratory flume experiments were conducted under the clear-water scour condition to investigate this effect. This study is the first that investigates experimentally the scour around group of bridge piers in cohesive bed. It was found that the maximum scour depth at the upstream pier of the two in-line piers occurred at a spacing of two times the diameter of the pier, scour at the downstream pier was reduced due to a sheltering effect, the interference effect will be reduced for pier spacings larger than three times of the pier diameter. A recent pier scour equation was used to estimate the scour depths at the two in-line piers in cohesive soil and compare the estimated value with the measured scour depths in the laboratory. The comparison indicated that the proposed scour equation overestimates the scour depths at both the upstream and the downstream pier.
4
Rashno, Emad, Amir Reza Zarrati, and Mojtaba Karimaei Tabarestani. "Design of riprap for bridge pier groups." Canadian Journal of Civil Engineering 47, no. 5 (May 2020): 516–22. http://dx.doi.org/10.1139/cjce-2019-0007.
Full textAbstract:
Stable riprap size and optimized extension of the riprap layer around double and triple piers along the flow direction are studied experimentally. Results showed that the critical riprap failure area and stable riprap size around the first pier remain unchanged with increasing pier spacing. In addition, the largest stable riprap should always be placed in front of the first pier in comparison with the remaining downstream piers. However, by increasing the pier spacing, stable riprap size around the second and third pier increased and approached that around the first pier. A relationship was developed for designing stable riprap size in pier groups. Based on this relationship, different riprap sizes are suggested for different zones around the pier group. Experiments showed that the critical zone around the piers includes only a small area and the rest of the riprap extent area can be protected with smaller riprap stones.
5
Ferregut, Carlos, and Miguel Picornell. "Reliability analysis of drilled piers in expansive soils." Canadian Geotechnical Journal 28, no. 6 (December 1, 1991): 834–42. http://dx.doi.org/10.1139/t91-101.
Full textAbstract:
Heavy structures in areas with expansive soils are commonly founded on piers resting beneath the surface active zone. During construction, the piers remain essentially unloaded and are exposed to potentially high tensile stresses that can split the pier unless the pier has been adequately reinforced. In this context, uncertainties arise relative to (i) the parameters governing the load transfer from the soil to the pier, (ii) the potential heave to be expected in a "free field" condition, when the soil movements are not restricted by the pier, and (iii) the estimation of the pier capacity to resist the induced stresses. Probabilistic models to handle and to quantify these uncertain parameters are constructed and then used to compute the probability of exceeding two potential limit states: (i) vertical pier head displacement and (ii) maximum tensile stress in a cross section of the pier. The displacements are used to assess the serviceability performance of the pier, and the maximum tensile stresses are used to estimate the reliability of the pier. Key words: piers, expansive soil, reliability, probability, foundations.
6
Wang, Chengquan, Zheng Qu, Yonggang Shen, Jiqing Jiang, Chongli Yin, and Yanwei Zong. "Numerical Investigation of the Performance of Segmental CFST Piers with External Energy Dissipators under Lateral Cyclic Loadings." Materials 15, no. 19 (October 9, 2022): 6993. http://dx.doi.org/10.3390/ma15196993.
Full textAbstract:
In order to improve the construction efficiency of piers and reduce the local damage of piers, concrete-filled steel tubes (CFST) are used to precast pier segments. Aiming at the problems of the poor integrity and insufficient energy dissipation capacity of dry joint segmental assembled piers, segmental assembled concrete-filled steel tubular piers with external replaceable energy dissipators are being developed. Based on the low cyclic test of a segmental assembled CFST pier, the finite element numerical simulation model of a CFST pier is established based on ABAQUS software, and the validity of the numerical model is verified by the experimental results. The effects of the section ratio, axial compression ratio, and initial prestress on the seismic performance of piers are studied through a pseudostatic analysis. The results show that an increase in the section ratio can improve the lateral bearing capacity and energy dissipation capacity of the pier. When the section ratio is increased to 4%, the energy dissipation capacity of a CFST pier is increased by 77.8% and the lateral bearing capacity is increased by 33.9% compared with a section ratio of 2%, but the residual displacement of the pier top also increases. With an increase in the axial compression ratio, the energy dissipation capacity of the pier is significantly improved; when the axial compression ratio is increased to 0.30, the energy dissipation capacity of CFST piers is increased by 27.5% compared with a section ratio of 0.05, the residual displacement of the pier top is reduced, and the self-resetting effect of the pier is improved. A change in the initial prestress has no effect on the energy dissipation capacity of piers. Finally, based on an analysis of mechanical theory, a formula of bending capacity suitable for this type of pier is proposed, and the error is within 10%.
7
Al-Shukur, Abdul-Hassan K., and Manar Hussein Ali. "Optimum Design for Controlling the Scouring on Bridge Piers." Civil Engineering Journal 5, no. 9 (September 1, 2019): 1904–16. http://dx.doi.org/10.28991/cej-2019-03091381.
Full textAbstract:
The scouring around bridge pier can be considered the most important reasons of bridge failure. Therefore, we investigated by using physical models of piers and we used single pier with square collar , circular collar and interaction of two piers in laboratory channel, its width 1 m and applied three velocities (0.1, 0.08, and 0.07) m/sec. This experimental investigation was made to choose the optimum shape and location of collar of single pier and comparing it with the interaction of two piers, the results showed that both square and circular collar decrease the scour depth, but the square collar is more effective of reducing scouring and the best location at bed level for single pier, comparing the results of single pier with the interaction of two piers, the interaction of two piers without any countermeasure reduced scour depth about 58%.
8
Zhang, Xianqi, Tao Wang, and Xiaobin Lu. "Influence of bridge piers shapes on the flow of the lower Yellow River." Water Practice and Technology 16, no. 2 (February 13, 2021): 661–80. http://dx.doi.org/10.2166/wpt.2021.011.
Full textAbstract:
Abstract The shape of bridge piers across rivers is one of the significant factors that affect the backwater in the river. The study on the influence of bridge pier shapes on the flow patterns of the river is valuable to the design of the bridge and river flooding. Based on the MIKE21 Flow Model hydrodynamic model, dynamic numerical simulations were conducted to investigate the effect of different shapes of bridge piers on water flow. The result shows that rectangular, circular and elliptical piers have a water blocking effect on the river. The flow patterns changed in local areas near the piers. Under the same flow rate, the backwater of the rectangular pier was the largest, followed by the circular piers, and the elliptical pier was the smallest. The value of backwater volume caused by the rectangular pier was 1.95 times the elliptical pier. The elliptical bridge piers basically do not change the overall flow patterns of the river, and have little effect on the river regime. This work provides a reference for the layout of river bridge piers.
9
Nie, Yun Jing, Xu Yan, and Tie Ying Li. "Influence of Tie Beams of Pier on the Seismic Performance of a Continuous Rigid Frame Bridge with Twin-Legged Piers." Advanced Materials Research 368-373 (October 2011): 1105–10. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.1105.
Full textAbstract:
In this paper, the influence of tie beams for piers is investigated on the dynamic characteristics and the seismic performance of a continuous rigid frame bridge with twin-legged piers. Modal analyses and the linear seismic response analyses are performed on a practical continuous rigid frame bridge with twin-legged piers with no tie beam, one tie beam and three tie beams of pier, using software Midas/civil. The findings indicate that installing tie beams of pier can increase the natural frequencies of this kind of bridge. Setting tie beams of pier is disadvantageous to the seismic performance of the bridge beam, but advantageous to improving the seismic performance of the twin-legged piers. The influence of tie beams of pier on the seismic performance on the whole structure is relevant to the pier height. These analytical results provide a reference for the seismic design and analysis of similar structures.
10
Thomas, Fairl Louise, and Elizabeth A. Forys. "The Role of Fishing Piers in Brown Pelican (Pelecanus occidentalis) Entanglement." Animals 12, no. 18 (September 8, 2022): 2352. http://dx.doi.org/10.3390/ani12182352.
Full textAbstract:
Throughout their range, Brown Pelicans (Pelecanus occidentalis) are one of the most common species to become entangled in fishing gear. We surveyed four piers every other week for one year (6/2019–5/2020) in the Tampa Bay region, FL, USA, to determine frequency of pelican entanglement associated with fishing piers, and explored factors that might influence the rate of entanglement. We conducted a generalized linear model (GLM) to determine the influence that pier, pier closure due to COVID-19, time of day and season, number of anglers, and presence of human behaviors that might attract pelicans to the pier had on the number of entangled pelicans. We conducted 144 surveys and counted 3766 pelicans of which 254 (7%) were entangled. The variables significantly associated (p < 0.05) with entanglement were the pier, time of day, and pier closure status, while the number and behavior of anglers were not significant. The two piers that most significantly influenced the number of entanglements both had extensive perches within 10 m of the fishing pier. The management action most likely to reduce the number of entangled pelicans appears to be deterring pelicans from perching near piers or decreasing fishing near perching structures.
11
Wang, Zhen, and Xiu Xin Wang. "Mechanical Properties of the Section from Steel Tube-Reinforced Concrete Pier." Applied Mechanics and Materials 744-746 (March 2015): 789–92. http://dx.doi.org/10.4028/www.scientific.net/amm.744-746.789.
Full textAbstract:
To research the impact of inner concrete filled steel tubular (CFST) on the reinforced concrete (RC) pier confined by stirrups, a Matlab program based on fiber model was written to calculate the moment-curvature (M-ϕ) relationship. The program was utilized to compute the M-ϕ relationships of three piers with same longitudinal bars and stirrups, and the three piers were an ordinary RC pier confined by stirrups、a high strength reinforced concrete (HSRC) pier confined by stirrups and a steel tube-reinforced concrete (ST-RC) pier respectively. The rules about bearing capacity of section and curvature ductility along with axial load N were deliberated by comparing the numeral results of three piers. The ratio of peak moment Mk to yield moment My was defined as super coefficient λs, and the disciplinarian of λs along with N was discussed. Participation factor ξ referred to the ratio of the moment provided by inner CFST to the total moment of ST-RC pier, and the laws of ξ affected by ϕ and N were researched. The results show that ST-RC pier has higher ductility and higher bearing capacity of section, and ductility decreases more slowly than other piers with the increase of N. λs of ST-RC pier is highest among three piers in most cases. On conditions of different N, ξ shows different variation trend with curvature ϕ up, and the maximum of participation factor ξmax is reckoned to be not affected by N basically.
12
Li, Jie, Yuanhong Hu, Dayu Yang, Tengda Feng, Yan Liang, and Chenchen Tao. "Feasibility Study of Using Engineered Cementitious Composite and High-Strength Bars in Rigid Bridge Piers Based on Seismic Vulnerability Analysis." Shock and Vibration 2020 (September 27, 2020): 1–11. http://dx.doi.org/10.1155/2020/8850800.
Full textAbstract:
The main function of pier is to transmit the load from superstructure to foundation reliably. Under earthquake action, the main failure reason of bridge is the damage of bridge pier. The application of some high-performance materials is helpful to improve the seismic performance of bridge piers. Based on seismic vulnerability analysis, this paper studies the feasibility of using engineered cementitious composite (ECC) and high-strength bars in bridge piers. Taking a rigid pier as an example, a nonlinear numerical model is established by OpenSees software. The reasonable replacement height of ECC in plastic hinge regions, stirrup ratio of pier section, and replacement rate of high-strength bars are obtained through the seismic performance analysis of the pier. Then, seismic vulnerability of rigid pier with ECC and high-strength bars is analyzed. The results show that it is feasible to improve the seismic performance of the piers by using ECC and high-strength bars. Considering the economic rationality, the replacement height of ECC in plastic hinge regions can be determined according to the curvature change point. For the rigid pier, the economical and reasonable volume stirrup ratio is 0.78%. The ultimate curvature of RC/ECC pier bottom increases by 12.4% when the longitudinal bars of the pier are replaced by high-strength bars, and the energy dissipation capacity increases by 22.5% on average. Compared with the pier’s original design, the exceedance probability of each limit state of the rigid pier with ECC and high-strength bars is significantly reduced. Its seismic performance is superior, and the risk of seismic damage is significantly reduced.
13
Qiu, Wen Liang, Meng Jiang, and Le Zhou. "Seismic Performance of Reinforced Concrete Pier with Inside Concrete Filled Steel Tube." Advanced Materials Research 163-167 (December 2010): 4194–98. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.4194.
Full textAbstract:
A reinforced concrete column with inside concrete filled steel tube (RC-CFT) has many advantages over reinforced concrete (RC) column, such as higher compression, shear and moment capacity, higher ductility. So this kind of composite column has been used as frame column in buildings. In this paper, the composite columns are used as piers of a continuous bridge to improve the seismic performance. Using nonlinear time-history analysis method and fiber element model, considering elasto-plastic nonlinearity, the nonlinear relationships between lateral load and horizontal displacement of RC-CFT pier and RC pier are calculated, and the seismic behaviors of continuous bridges with the two types of piers are analyzed. Based on the comparison of the results, it is found that the ductility of RC-CFT pier is much larger than RC pier. Under the same intensity earthquakes, the damage of RC-CFT pier is less than the RC pier, and RC-CFT pier is more safe and easy to be repaired after earthquake.
14
Lakusic, Stjepan. "Simulation of Scour at Bridge Supports." Journal of the Croatian Association of Civil Engineers 72, no. 09 (October 2020): 793–801. http://dx.doi.org/10.14256/jce.2506.2018.
Full textAbstract:
Groups of piers are used on bridges to minimise scour around bridge supports. The prediction of scour around piers due to interaction of vortices around bridge piers is more complex compared to scour prediction around a single pier. Four arrangements of bridge piers with different spaces in the lateral and longitudinal directions are investigated under clear water conditions to observe scour generation around bridge foundations. The experimental study is performed in a rectangular open channel. A 3D numerical study based on fluid dynamics is also conducted. Results show that different pier group arrangements produce smaller scour holes than a single pier.
15
Abbas, Fakhar Muhammad, Usman Ali Naeem, Usman Ghani, Amina Khan, and Talat Farid Ahmad. "Experimental Study of Inclined Bridge Pier Scouring." Mehran University Research Journal of Engineering and Technology 39, no. 4 (October 1, 2020): 859–70. http://dx.doi.org/10.22581/muet1982.2004.18.
Full textAbstract:
The bridges are one of important structures in any country. The failure of bridges occurs due to many factors including design flaws and manufacturing construction errors. Among all imperfections scouring around the pier is the most detrimental. So, the estimation of local scouring around a bridge pier is of fundamental importance for the safe design of bridges. Although numerous researches have been done on local scouring around a single bridge pier. The present study investigates the effect of angle of inclination of dual bridge pier configuration on local scouring around bridge piers. Principally rectangular shaped dual bridge piers were installed in sand bed of laboratory flume at angle of inclination of 0°,7°,12°,15° and 19° with vertical respectively. Three different flow rates 9, 14 and 18L/sec were considered during each trial. The duration of each trial was kept around 2 hours. The scour depth was measured separately around both piers with the help of point gauge under clear water condition. The value of scour depth around upstream pier was larger as compared to downstream pier because of the lower strength of horseshoe vortices around downstream pier. From the experimental results, it can be concluded that there is an inverse relationship between the angle of inclination and scour depth, an increase in the angle of inclination leads to decrease in scour depth around both piers. The value of scour depth was maximum when piers were at 0° and minimum at 19°. It was also found that scour depth increases with the increase in flow rate.
16
Yao, Zhan Yong, Xiao Meng Zhang, Shuai Li, Lian Fu Li, Xiang Hong Pan, and Kai Yao. "Influence of Closure Sequences on the Rigid Frame-Continuous Girder Bridge Closure." Applied Mechanics and Materials 361-363 (August 2013): 1422–28. http://dx.doi.org/10.4028/www.scientific.net/amm.361-363.1422.
Full textAbstract:
Closure sequences of rigid frame-continuous girder bridge are analyzed by calculation to compare girder deflection change, pier horizontal displacement maximum, girder and pier stress value. The results show that the first side span-second side span-mid span closure sequence causes the largest girder vertical displacement and others cause almost the same vertical displacement; side piers pier top horizontal displacement is larger than middle piers whatever the closure sequence is, closure sequences could not change the stress of the girder and pier. The first side span-mid span-second side span closure sequence should be preferred.
17
Deng, Baodong, Yanmin Jia, and Dongwei Liang. "Study on the Seismic Performance of Prefabricated Single-Segment Steel Jacket Bridge Piers." Symmetry 13, no. 12 (December 3, 2021): 2312. http://dx.doi.org/10.3390/sym13122312.
Full textAbstract:
To study the seismic performance of prefabricated single-segment steel jacket piers connected by grouting sleeves, two scaled symmetrical pier models with different anchorage lengths of the longitudinal reinforcement in the grouting sleeves and a comparative symmetrical cast-in-place (CIP) model were designed. OpenSees finite element models were established and shaking table tests were carried out on the three scaled pier models. The seismic response of each pier was compared and analyzed. Results showed the stiffness of the two prefabricated piers was greater than that of the CIP pier, and other seismic responses were less than those of the CIP piers, The dynamic responses of the two prefabricated bridge models were similar and changing the anchorage length of the reinforcement in the grouting sleeve had little effect on the seismic performance of the prefabricated pier. The simulation results were in good agreement with the experimental results. In the parameter analysis, the counterweight of the pier top had the greatest influence on the seismic performance of the prefabricated pier. The anchorage length of the longitudinal reinforcement in the grouting sleeve could be 6–14 times the diameter of the longitudinal reinforcement. Moreover, the seismic performance was found to be optimal when the thickness of the steel jacket was 5–7 mm.
18
Deng, Jiang Dong, Zhou Hong Zong, and Zhang Hua Xia. "Study on Seismic Strengthening Demand of Damage Concrete Bridge Piers." Applied Mechanics and Materials 178-181 (May 2012): 2070–74. http://dx.doi.org/10.4028/www.scientific.net/amm.178-181.2070.
Full textAbstract:
Initial damage often exists in the concrete piers of bridges in service. In this paper numerical analysis was used to study the seismic strengthening behavior of concrete bridge piers with different bending damage degrees, including seismic forces, pier top displacements, steel bar strain and energy dissipation, in order to obtain the strengthening demand to repair the damage piers. The results showing that: initial bending damage reduced the seismic force, increased the pier top displacements and the steel bar strain. After strengthening the pier top displacements and steel bar strain at the pier bottom decreased, energy dissipation increased, and the anti-seismic properties of damage piers effectively recovered, but the increase of the seismic force might make new plastic-hinges out the strengthened area. At last according to the mechanics properties the strengthening demand under different bending damage degrees was given.
19
Bestawy, A., T. Eltahawy, A. Alsaluli, A. Almaliki, and M. Alqurashi. "Reduction of local scour around a bridge pier by using different shapes of pier slots and collars." Water Supply 20, no. 3 (February 14, 2020): 1006–15. http://dx.doi.org/10.2166/ws.2020.022.
Full textAbstract:
Abstract Local scour around bridge piers is one of the main causes of bridge failure all over the world. Experimental and hydraulic models were carried out to investigate two types of scour reduction methods around a single cylindrical pier, namely the pier's slots and collars. The efficiency of various types of pier slots and circular collars around the pier's base in reducing scour were studied. A new shape of a conical collar was developed by the authors and examined along with other shapes. The results revealed that collars, in general, have more influence in reducing scour depth than slots made in the front and rear of bridge piers. The sigma-slot acts better than other tested slots, with a reduction in the scour depths of 59.3% and 52.8% at the upstream and downstream of the pier, respectively. On the other hand, the conical collar appeared to be the most effective collar shape in reducing the scour around the bridge pier, with a 61.1% reduction in the scour depth downstream of the pier. A three-dimensional laser scanner was used to capture the bed topography at the end of each experiment and contour maps of the deformed bed were produced. A one-dimensional Hydrologic Engineering Center-River Analysis System model was developed with a single bridge pier to predict the scour depth around the pier in an attempt to introduce new values for the pier nose shape factor, , which describes the tested piers.
20
Wang, Jie, Jin Yun Zhao, and Jian Xin Liu. "Experimental Study of Aerodynamic Interference Effects on Double Thin-Walled Hollow Pier in Tandem Arrangement." Advanced Materials Research 368-373 (October 2011): 1517–20. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.1517.
Full textAbstract:
Against the problem of the aerodynamic interference effects on aerostatic coefficients between parallel continuous rigid frame bridges with high-pier and long-span, the aerodynamic interference effects on aerostatic coefficients of double thin-walled hollow pier in the parallel long-span continuous rigid frame bridges were investigated in details by means of wind tunnel test．The space between the two piers and wind direction angles were changed during the wind tunnel test to study the effects on aerodynamic interferences of aerostatic coefficients of twin piers. The test got aerostatic coefficients of 8 conditions. The research results have shown that the aerodynamic interference effects on aerostatic coefficients of double thin-walled hollow pier in parallel bridges can not be ignored. The aerodynamic interference effects on parallel bridge pier is shown mainly as follows: The tandem interval and wind direction angles are important factors affecting interference effects. The drag coefficient of pier downstream dropped and the drag coefficient of pier upstream changed but Not change significantly. There are also the aerodynamic interference effects of lateral force coefficient and torque coefficient between the piers upstream and downstream. The effects upstream are smaller and the effects downstream are larger.
21
Rowe, R. K., and H. H. Armitage. "Theoretical solutions for axial deformation of drilled shafts in rock." Canadian Geotechnical Journal 24, no. 1 (February 1, 1987): 114–25. http://dx.doi.org/10.1139/t87-010.
Full textAbstract:
A theoretical examination of a number of factors affecting the behaviour of drilled piers in soft rock is presented. Firstly, the fundamental difference between tests commonly used for determining the peak average side shear resistance along a socketed pier is discussed. Secondly, the effect of interface strength parameters, dilatancy, and the relative Young's modulus of the pier and rock upon the average mobilized side shear resistance is examined. Thirdly, a series of theoretical solutions are presented in the form of design charts to provide a simple means of estimating the load—deflection response of piers both before and after full slip has developed along the pier shaft. Finally, the effect of weak horizontal seams adjacent to the pier is considered. Key words: drilled shafts, piers, piles, rock, theory, settlement, displacement, analysis.
22
Wu, Bo, and Shixiang Xu. "Experimental study on damage evaluation of stainless steel–reinforced concrete piers under lateral impact." Advances in Mechanical Engineering 12, no. 5 (May 2020): 168781402092488. http://dx.doi.org/10.1177/1687814020924886.
Full textAbstract:
Horizontal impact tests of stainless steel–reinforced concrete piers with different reinforcement ratios at different impact velocities were carried out by using the ultra-high drop weight impact test system. Degree of piers damage after impact was comprehensively analyzed by measuring the acceleration of the impact body, the displacement of the top of the pier specimens, the strain of the steel bars, the rotation of the pier bottom, and the crack development of concrete. The test results showed that under the same impact velocity, with the decrease in reinforcement ratio, the peak acceleration of the impact body, the displacement of the top of pier specimens, the strain of steel bars, and the pier bottom rotation all increase. To a certain extent, increasing the reinforcement ratio of bridge piers can effectively reduce impact damage.
23
Joo, Hyung Joong, Seung Sik Lee, Soon Jong Yoon, Joo Kyung Park, and Sun Kyu Cho. "Seismic Performance of Bridge Pier with FRP Wrapping." Key Engineering Materials 326-328 (December 2006): 1717–20. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.1717.
Full textAbstract:
This paper presents the results of an experimental study on the seismic performance of reinforced concrete (RC) bridge piers wrapped with FRP at the lap-spliced region. It is well known that the FRP wrapping on the surface of concrete bridge pier can prevent concrete cover from spalling and it can reduce the slip displacement of lap-spliced longitudinal re-bars due to confinement. In order to develop the effective way of strengthening the concrete bridge pier with poor lap-spliced longitudinal re-bars, which is not designed under seismic design consideration, a series of pier test under seismic loading condition is conducted. As a result, FRP wrapped bridge pier under seismic loading exhibits ductile behavior with plastic deformation at lap-spliced region. Half-scaled six circular and nine square pier specimens were tested under uniform concentric axial compression and quasi-static lateral loading at the top of the pier. For the purpose of comparison, two piers without lap-splice and two piers with lap-splice were not wrapped with FRP and tested under same loading condition. Other experimental parameters were the height of FRP wrapping and the reinforcing method. The experimental results showed that the FRP wrapping could significantly increase ductility of piers with lap-spliced longitudinal re-bars at the potential plastic hinge region.
24
Lee, Wei-Lin, Chih-Wei Lu, and Chin-Kun Huang. "A Study on Interaction between Overfall Types and Scour at Bridge Piers with a Moving-Bed Experiment." Water 13, no. 2 (January 11, 2021): 152. http://dx.doi.org/10.3390/w13020152.
Full textAbstract:
River slopes can be changed due to an extreme event, e.g., a large-scale earthquake. This can uplift a riverbed greatly and thereby change the behavior of the river flow into a free or submerged overfall. Corresponding damage, including extreme erosion, on bridge piers located in the river can take place due to the aforementioned flow conditions. A reconstructed bridge pier in the same location would also experience a similar impact if the flow condition is not changed. It is important to identify these phenomena and research the mechanism in the interaction between overfall types and scour at bridge piers. Therefore, this paper is aimed at studying a mechanism of free and submerged overfall flow impacts on bridge piers with different distances by a series of moving-bed experiments. The experiment results showed clearly that bridge pier protection requires attention particularly when the pier is located in the maximum scour hole induced by the submerged overfall due to the z directional flow eddies. In many other cases, such as when the location of the bridge pier was at the upstream slope of a scour hole induced by a flow drop, a deposition mound could be observed at the back of the pier. This indicates that, while a pier is at this location, an additional protection takes place on the bridge pier.
25
Lee, Wei-Lin, Chih-Wei Lu, and Chin-Kun Huang. "A Study on Interaction between Overfall Types and Scour at Bridge Piers with a Moving-Bed Experiment." Water 13, no. 2 (January 11, 2021): 152. http://dx.doi.org/10.3390/w13020152.
Full textAbstract:
River slopes can be changed due to an extreme event, e.g., a large-scale earthquake. This can uplift a riverbed greatly and thereby change the behavior of the river flow into a free or submerged overfall. Corresponding damage, including extreme erosion, on bridge piers located in the river can take place due to the aforementioned flow conditions. A reconstructed bridge pier in the same location would also experience a similar impact if the flow condition is not changed. It is important to identify these phenomena and research the mechanism in the interaction between overfall types and scour at bridge piers. Therefore, this paper is aimed at studying a mechanism of free and submerged overfall flow impacts on bridge piers with different distances by a series of moving-bed experiments. The experiment results showed clearly that bridge pier protection requires attention particularly when the pier is located in the maximum scour hole induced by the submerged overfall due to the z directional flow eddies. In many other cases, such as when the location of the bridge pier was at the upstream slope of a scour hole induced by a flow drop, a deposition mound could be observed at the back of the pier. This indicates that, while a pier is at this location, an additional protection takes place on the bridge pier.
26
Nagao, T., and Y. Kurachi. "An Experimental and Analytical Study on the Seismic Performance of Piers with Different Foundation Bottom Widths." Engineering, Technology & Applied Science Research 12, no. 5 (October 2, 2022): 9142–48. http://dx.doi.org/10.48084/etasr.5088.
Full textAbstract:
Piers can be severely damaged by earthquakes. When an action of a massive earthquake is assumed, the seismic performance of the pier can be improved by widening the foundation width. A previous horizontal loading study indicated that extending only the Foundation Bottom (FB) width, rather than the complete foundation, can boost seismic resilience while suppressing the increase in building cost. However, the research dealt with only two types of FB width, i.e. normal and widened, and the data for sufficiently assessing the inclination angle of the pier with loading were not obtained. In this study, to evaluate the seismic performance of piers with different FB widths in more detail, horizontal loading tests on piers with ordinary columnar foundations and two types of piers with widened FB were conducted, and the seismic resistance of the three pier types were compared. It was shown that horizontal displacement and inclination angle of the pier can be reduced by widening the FB. Furthermore, finite element analysis was carried out to reproduce the experimental results. The analysis results showed good agreement with the experimental results in terms of pier horizontal displacement and inclination angle.
27
Song, Guohua, Minghui Li, and Delu Che. "Construction Stability Analysis of Curved Continuous Rigid Frame Bridges with High Piers." MATEC Web of Conferences 206 (2018): 01017. http://dx.doi.org/10.1051/matecconf/201820601017.
Full textAbstract:
Taking the curved continuous rigid frame bridges (CRFBs) with high piers as research object, the construction stability of four different styles of main piers were analyzed by finite element (FE) method in three construction stages including the segment 0 stage, largest cantilever stage, and finished bridge stage. Rules governing the stabilities of bridges with various pier styles, height, and slenderness ratio were established. At different construction stages, pier type and pier height affect structural stability differently. Wind loads have little influence on structural stability at any construction stage, and accidental events influence the stability of bridges more than normal construction loads. There is a nonlinear power relationship of fixed functional type between the stability safety factor (SSF) and slenderness ratio in all four pier styles; this power relationship can be used to predict the stability of a new pier.
28
Guemou, Bouabdellah, Abdelali Seddini, and Abderrahmane Nekkache Ghenim. "Scour around Bridge Piers: Numerical Investigations of the Longitudinal Biconcave Pier Shape." Periodica Polytechnica Mechanical Engineering 62, no. 4 (August 1, 2018): 298–304. http://dx.doi.org/10.3311/ppme.12263.
Full textAbstract:
The flow pattern around a bridge pier and the scouring phenomenon are very complicated. The basic mechanism causing local scour is the down-flow at the upstream face of the pier. It is understood that the horseshoe vortex is the key mechanism that leads to the local scour around pier; existing literature revealed that the strength of the down-flow, horseshoe vortex and the wake vortex are greater in the case of square piers compared to circular piers. In this paper we have investigated a new longitudinal biconcave bridge pier shape that reduces better the bed shear stress. For that purpose, a number of numerical simulations have been carried out using a Finite Volume Method (FVM) and for the turbulence model we have chosen the Detached Eddy Simulation (DES) for its capability to capture the rich dynamics of the horseshoe vortex at the upstream junction between the pier and the bed.The present study shows that the new longitudinal biconcave bridge pier shape reduces 10 % to 12 % the bed shear stress at the junction between the pier and the bed in other hand this shape increases the bed shear stress about 20 % but at a distance of D downstream the bridge pier in the flow direction.
29
Chen, Ling Kun, and Li Zhong Jiang. "Inelastic Displacement Spectra for Displacement-Based Seismic Design of High-Speed Railway Bridge Pier." Applied Mechanics and Materials 121-126 (October 2011): 892–96. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.892.
Full textAbstract:
The inelastic displacement spectra is established based on the elastic displacement spectra and the strength reduction factor, the calculation process of Displacement-Based Seismic Design is presented in this paper, the seismic design of high-speed railway bridge piers is conducted to verified the method. The calculation results show that, at the same performance target, the pier height is taller, the cross-section is bigger; at the same pier height, the performance target is higher, the cross-section of pier is bigger; the reinforcement ratio with the different pier height and performance target are the lower limit of calculation value, it mean that the lateral reinforcement ratio of piers can just meet the detailing requirements.
30
Cai, Zhehan, Zhijian Wang, Kaiqi Lin, Ying Sun, and Weidong Zhuo. "Seismic Behavior of a Bridge with New Composite Tall Piers under Near-Fault Ground Motion Conditions." Applied Sciences 10, no. 20 (October 21, 2020): 7377. http://dx.doi.org/10.3390/app10207377.
Full textAbstract:
Currently, the seismic designs of reinforced concrete (RC) bridges with tall piers are often accomplished following the ductility-based seismic design method. Though the collapses of the RC bridges with tall piers can be avoided, they are likely to experience major damage and loss of functionality when subjected to strong near-fault ground motions. The objectives of this study are to put forward an innovative design concept of a tall-pier system and its application in tall-pier bridges. The concept of the innovative tall-pier system is derived from the principle of earthquake-resilient structures, and is to improve the seismic performances of the tall-pier bridges under strong near-fault ground motions. The proposed tall-pier system has a box section and is composed of four concrete-filled steel tubular (CFST) columns and energy dissipating mild steel plates (EDMSPs). Trial design of a bridge with the new composite tall-pier system is performed based on a typical continuous rigid frame highway bridge with conventional RC box section tall piers. Both static analysis and nonlinear time history analysis of both the bridges with the new composite tall piers and conventional RC tall piers under the near-fault velocity pulse-type ground motions were conducted in Midas Civil2019 and ABAQUS. The results show that: under the design-based earthquake (DBE), the CFST columns and connecting steel beams remain elastic in the bridge with the new composite tall piers, while the damage is found in the replaceable EDMSPs which help dissipate the seismic input energy. The displacement responses of the new bridge are significantly smaller than those of the conventional bridge under DBE. It is concluded that the bridge with the new composite tall piers is seismic resilient under near-fault ground motions.
31
Sha, Yanyan, and Hong Hao. "Laboratory Tests and Numerical Simulations of CFRP Strengthened RC Pier Subjected to Barge Impact Load." International Journal of Structural Stability and Dynamics 15, no. 02 (February 3, 2015): 1450037. http://dx.doi.org/10.1142/s0219455414500370.
Full textAbstract:
Bridge piers are designed to withstand not only axial loads of superstructures and passing vehicles but also out-of-plane loads such as earthquake excitations and vessel impact loads. Vessel impact on bridge piers can lead to substantial damages or even collapse of bridge structures. An increasing number of vessel collision accidents have been reported in the past decade. A lot of researches have been conducted for predicting barge impact loads and calculating structural responses. However, in practice it is not possible to design bridge structures to resist all levels of barge impact loads. Moreover, with an increasing traffic volume and vessel payload in some waterways, the bridge piers designed according to previous specifications might not be sufficient to resist the current vessel impact loads. Therefore, strengthening existing bridge piers are sometimes necessary for protecting structures from barge impact. Carbon fiber reinforced polymer (CFRP) has been widely used in strengthening reinforced concrete structures under impulsive loadings. It is an effective material which has been proven to be able to increase the flexural strength of structures. In this study, CFRP composites are used to strengthen reinforced concrete piers against barge impact loads. Pendulum impact tests are conducted on scaled pier models. Impact force and pier response with and without CFRP strengthening are compared. The effectiveness of using CFRP strengthening the pier model is observed. In addition, numerical models of the bridge piers are developed and calibrated with experimental results. Parametric simulations of barge impacting on piers with or without CFRP strengthening are carried out. The results show that compared with unstrengthened pier, CFRP composite strengthened bridge pier has a higher impact resistance capacity and hence endures less structural damage under the same barge impact load. The effectiveness of CFRP strengthening with different CFRP thickness, CFRP strength and bond strength between the pier and the CFRP composite are also discussed.
32
Nesterova, Olga. "On the problem of using the bridge span as a tuned mass damper of bridge pier oscillation." Bulletin of scientific research results, no. 1 (March 28, 2019): 24–30. http://dx.doi.org/10.20295/2223-9987-2019-1-24-30.
Full textAbstract:
Objective: To identify the area of effective use of bridge span as a tuned mass damper of bridge pier oscillation during earthquake in seismic areas. Methods: Numerical simulation of oscillations of the “bridge pier with span” system under both the impact set by the harmonic rule and the records of past earthquake accelerograms. Results: The area of effective use of bridge span structures as a tuned mass damper of bridge piers’ oscillation during earthquake in seismic areas has been defined. The concept of the relative critical mass of the span used as a tuned mass damper of bridge piers’ oscillation during earthquake has been introduced. When the spun structure mass reaches the critical value, the effect of the tuned mass damper disappears. The dependences of the optimal parameters of the connection between the span and pier on the relative span mass used as a tuned mass damper have been obtained. It has been found that the span critical mass used as a tuned mass damper decreases when the pier damping increases, and the dependences of the optimal parameters of the connection between the span structure and the pier on the damping in the pier body have been obtained. Practical importance: The possibility of using span as a tuned mass damper of piers is shown. The optimum characteristics of the span and its connection with the pier body have been obtained to be used in designing. The use of span as a tuned mass damper in piers can significantly reduce labor input and the cost of bridge building in seismic areas. It also facilitates the elimination of consequences of devastating earthquakes.
33
Hu, Sicong, Kaiwen Shao, Xiang Liu, Ziqiang Ma, and Baokui Chen. "Predictions and Evolution Characteristics of Failure Modes of Degenerate RC Piers." Buildings 13, no. 1 (January 1, 2023): 113. http://dx.doi.org/10.3390/buildings13010113.
Full textAbstract:
During the service process, piers are often in harsh chloride ion erosion environments. The failure mode evolution of reinforced concrete (RC) piers may occur under the action of continuous corrosion. Accurately identifying the failure mode types and evolution characteristics of corroded RC bridge piers is a prerequisite for the lifetime seismic performance evaluations of bridges. First, based on Fisher’s theory and 174 RC pier columns as the analysis samples, a two-stage discrimination formula for the pier failure modes was established and compared with the existing theoretical discrimination methods. Then, based on Fisher’s discriminant grouping, and combined with Bayes’ formula and chloride erosion theory, a failure mode discrimination method for corrosion-damaged bridge piers that considers probability was developed. Finally, taking a medium-span concrete bridge as an example, the failure modes of the corroded pier in different service periods were predicted, and the influences of the various parameters on the failure mode evolution process of the corroded pier were studied. The results show that the accuracy of the proposed discriminant model was significantly improved compared with those of previous theoretical studies. The development of the failure mode features depends on how the distinct RC pier material qualities degrade under the influence of chloride ions. The degradation of the stirrups and concrete accelerates the nonductile failure of RC bridge piers, while the degradation of the longitudinal reinforcements delays it.
34
Zhu, Mei-Liang, Li-Qing Zhang, Ye Ma, and Shun-Kun Jiang. "Stability Analysis of High-Pile and high-pier Considering Initial Pier Deviation." E3S Web of Conferences 261 (2021): 02050. http://dx.doi.org/10.1051/e3sconf/202126102050.
Full textAbstract:
Based on the high-pile and high-pier bridge of Qianhuang Expressway, eigenvalue buckling analysis is carried out by establishing three-dimensional finite element models of three different bridge types and high-pier types, and the corresponding structural nonlinear buckling loads under different initial pier deviations are calculated. The calculation results show that the nonlinear buckling loads of three high-pier types are less than elastic buckling loads. The stability of column high-pile and high-pier of continuous bridge is better than that of simple supported bridge, and the stability of plate high-pier is better than that of other two high-piers. In addition, the corresponding buckling load decreases with the increase of the initial horizontal displacement, indicating that the pier top offset of the high-pile and high-pier bridge is not conducive to the stability of the structure.
35
Yang, Meng, Yanmin Jia, and Dongwei Liang. "Shaking Table Tests and Simulations of Grouting Sleeve Connecting Prefabricated Bridge Piers." Symmetry 14, no. 4 (March 23, 2022): 652. http://dx.doi.org/10.3390/sym14040652.
Full textAbstract:
To investigate the seismic performance of prefabricated piers with a grouting sleeve connection, two scaled model specimens of symmetrical prefabricated piers with different reinforcement anchorage lengths, and two cast-in-place (CIP) comparison symmetrical specimens, were designed and manufactured. The fabricated specimens were connected by a grouting sleeve, which was in the column of the pier. The height of the pier column of the test piece was 1.425 m, the diameter of the pier column was 0.25 m, and the size of the bearing platform was 0.85 m × 0.85 m × 0.5 m. Shake table tests were performed on the specimens to evaluate crack development, dynamic characteristics, acceleration response and relative displacement of the pier tops, as well as strain in the plastic hinge area. The results revealed the dominant failure mode of the test piers was bending failure, while the cracks were generally horizontal through-cracks. The failure location of the prefabricated specimens with the grouting sleeve was concentrated within one diameter of the pier in the upper sleeve region. Compared with the CIP specimens, the plastic hinge exhibited an obvious upward movement. Under a maximum test loading condition, the peak acceleration at the pier top of the fabricated pier was 11.0% smaller than that of the CIP specimen, the peak relative displacement was 34.2% smaller than that of the CIP specimen, and the peak tensile strain of the pier body was 46.8% smaller. The seismic performance of the prefabricated pier connected via the grouting sleeves was barely affected by changing the anchoring length of the reinforcements in the grouting sleeves. An ABAQUS finite element model was established for the specimens, with good agreement between the model and experimental results. When the seismic load was 0.65 g, the difference between the peak acceleration of the pier top in the X direction and the Y direction of the numerical simulation and the experimental data was less than 15%.
36
Niu, Lijun, and Wenfang Zhang. "Experimental Study on a Self-Centering Earthquake-Resistant Masonry Pier with a Structural Concrete Column." Advances in Materials Science and Engineering 2017 (2017): 1–15. http://dx.doi.org/10.1155/2017/6379168.
Full textAbstract:
This paper proposes a slotting construction strategy to avoid shear behavior of multistory masonry buildings. The aspect ratio of masonry piers increases via slotting between spandrels and piers, so that the limit state of piers under an earthquake may be altered from shear to rocking. Rocking piers with a structural concrete column (SCC) form a self-centering earthquake-resistant system. The in-plane lateral rocking behavior of masonry piers subjected to an axial force is predicted, and an experimental study is conducted on two full-scale masonry piers with an SCC, which consist of a slotting pier and an original pier. Meanwhile, a comparison of the rocking modes of masonry piers with an SCC and without an SCC was conducted in the paper. Experimental verification indicates that the slotting strategy achieves a change of failure modes from shear to rocking, and this resistant system with an SCC incorporates the self-centering and high energy dissipation properties. For the slotting pier, a lateral story drift ratio of 2.5% and a high displacement ductility of approximately 9.7 are obtained in the test, although the lateral strength decreased by 22.3% after slotting. The predicted lateral strength of the rocking pier with an SCC has a margin of error of 5.3%.
37
Li, Yu, Yan Yang Che, and Sen Wang. "Improved Seismic Checking for Pier Based on Seismic Energy Response Method." Applied Mechanics and Materials 455 (November 2013): 224–27. http://dx.doi.org/10.4028/www.scientific.net/amm.455.224.
Full textAbstract:
Based on prophase research work, seismic checking for pier based on energy method is improved. The seismic input energy demand of pier is determined by using the seismic input energy response spectra and hysteretic energy dissipation spectra of sing-degree-of-freedom. Meanwhile, the Pushover Method is used to determine the hysteretic deformation capacity of pier. Then, based on the equilibrium principal between hysteretic deformation capacity and seismic input energy demand of pier, seismic checking for pier is carried on. Then, this improved seismic checking for pier based on energy method is applied in the design examples of piers. Comparing with the calculation of nonlinear time history analyses, it is known that improved seismic checking for pier based on energy method can evaluate the seismic performance of pier effectively. So, these valuable results can provide the meaningful reference for the seismic design of bridge engineering.
38
Song, Fangyuan, Tingting Zhang, and Xu Xie. "Effect of Corroded Surface Morphology on Ultra-Low Cycle Fatigue of Steel Bridge Piers." Materials 14, no. 3 (February 1, 2021): 666. http://dx.doi.org/10.3390/ma14030666.
Full textAbstract:
Corrosion is a common form of durability degradation of steel bridges. Corrosion morphology affects stress distribution under cyclic loads and causes strain concentrations in pits, thus affecting the mechanical properties of steel structures, including ultra-low cycle fatigue (ULCF). To precisely simulate corrosion morphology and investigate the ULCF failure mechanism of corroded steel piers, a sculpting method was applied to mesh units using three-dimensional surface morphology data of corroded steel specimens. Moreover, the ULCF crack-initiation life was numerically predicted using the finite element model based on the cyclic void growth model (CVGM). The cumulative equivalent plastic strain, cyclic void growth index, and critical void growth index of corroded steel piers with different corroded morphologies were compared. Results reveal that, regardless of whether the pier is corroded, fatigue cracks tend to initiate at the weld toe at corners when exposed to cyclic loads under an oblique direction at the pier top. Additionally, the ULCF crack-initiation life in a corroded pier is less than that in an uncorroded pier, and it is significantly affected by a reduction in the pier wall thickness. Corrosion pits affect the position of ULCF crack initiation in a steel pier and cracks tend to initiate at the bottom of pits with large depth-to-diameter ratios. In the case of minor corrosion, the corrosion morphology affects the seismic performance of piers to a small extent.
39
Ahmad, Nursafarina, Azmi Ibrahim, and Shahria Alam. "Analytical Seismic Fragility Curves for Reinforced Concrete Wall pier using Shape Memory Alloys considering maximum drift." MATEC Web of Conferences 258 (2019): 04001. http://dx.doi.org/10.1051/matecconf/201925804001.
Full textAbstract:
Fragility curves express the seismic vulnerability of bridge piers for different damage states at various earthquake intensities. A fragility curve typically gives a physical understanding of repair costs and functionally levels of a bridge pier. Shape memory alloys (SMAs) provide a promising alternative material in reducing the failure probability of a bridge pier. This study develops a family of seismic fragility curves for reinforced concrete (RC) wall piers reinforced with three different types of SMA rebar in plastic hinge regions. An incremental dynamic analysis (IDA) using a total of 20 earthquake ground motions was performed on a SMA-RC wall pier to evaluate its seismic performance. The maximum drift recorded for each ground motion was taken as the seismic performance demand parameter of interest in this study. The probabilistic seismic demand model (PSDM) was used to generate fragility curves for each RC-SMA wall pier. The results show that the different mechanical properties and type of SMAs affect the performance of RC-SMA wall pier.
40
Xu, Junming, Yanmin Jia, and Dongwei Liang. "Shaking table test on single segment prefabricated concrete bridge pier connected by grouting sleeve." International Journal of Structural Integrity 13, no. 1 (November 9, 2021): 164–84. http://dx.doi.org/10.1108/ijsi-07-2021-0079.
Full textAbstract:
PurposePrefabricated pier technology has the advantages of quick construction time, relatively little traffic interference and relatively small environmental impact. However, its applicability under earthquake conditions is not yet fully understood. The seismic performance and influence parameters of a prefabricated concrete pier connected by embedded grouting sleeve (GS) in a pile cap are investigated in this study.Design/methodology/approachTwo prefabricated pier scale model specimens with different reinforcement anchorage lengths and two comparative cast-in-place (CIP) pier model specimens are designed and manufactured for a seismic simulation shaking table. With the continuous increase of input ground motion strength, the changes in basic dynamic characteristics, damage development, acceleration and displacement variation laws, and pier bottom strain responses are compared among the specimen. The finite element software ABAQUS is used to simulate the test pier.FindingsThe crack location of the two prefabricated pier specimens is almost the same as that of the CIP pier specimens; CIP pier specimens show more penetrated cracks than prefabricated pier specimens, as well as an earlier crack penetration time. The acceleration, displacement and strain response of the CIP pier specimens are more affected by earthquake activity than those of the prefabricated pier specimens. The acceleration, displacement and strain responses of the two prefabricated piers are nearly identical. The finite element results are in close agreement with the acceleration and displacement response data collected from the test, which verifies the feasibility of the finite element model established in ABAQUS.Originality/valueA GS connection method is adopted for the prefabricated pier, and on the premise of meeting the minimum reinforcement anchorage length required by the code, this study explores the influences of different reinforcement anchorage lengths on the seismic performance of prefabricated piers in high-intensity areas. A shaking table loading test is used to simulate the real changes of the structure under the earthquake. This work may provide a valuable reference for the design and seismic performance analysis of prefabricated pier, particularly in terms of seismic stability.
41
Li, Junhong, and Junliang Tao. "Streamlining of Bridge Piers as Scour Countermeasures." Transportation Research Record: Journal of the Transportation Research Board 2521, no. 1 (January 2015): 162–71. http://dx.doi.org/10.3141/2521-17.
Full textAbstract:
Bridge scour is one of the most critical causes of bridge failure. Existing scour countermeasures either passively prevent the development of scour holes by stabilizing the critical shear zone or actively reduce the turbulence intensity in the vicinity of the pier surface. This paper proposes streamlining of the bridge pier as an option to reduce turbulence intensity actively in the local zone and thus decrease overall local scour potential. The effect of the curvature of the pier cross section was evaluated with computational fluid dynamics (CFD) simulations. To reduce computational cost, two-dimensional CFD simulations were conducted to model the flow fields around test cases having different pier cross sections. Simulation results were systematically analyzed and compared to evaluate the effect of streamlining on the flow field. The cross section that resulted in the smallest value of the maximum bed shear stress was selected as the optimal cross section for the subsequent three-dimensional (3-D) study, which investigated the vortex structures around the pier. Results from this 3-D simulation were compared with those from two other test cases, in which piers had cross-section shapes that are commonly seen in practice. The pier model with the optimal cross section was found to significantly reduce the downward velocity in front of the piers, the maximum bed shear stress, and the overall scour potential. These findings are expected to inform the design of optimal streamlined piers for newly proposed bridges, which could diminish the overall scour potential around piers.
42
Memar, Sargol, Mohammad Zounemat-Kermani, Ali-Asghar Beheshti, Giovanni De Cesare, and Anton J. Schleiss. "Investigation of local scour around tandem piers for different skew-angles." E3S Web of Conferences 40 (2018): 03008. http://dx.doi.org/10.1051/e3sconf/20184003008.
Full textAbstract:
In the present study the effect of the skew-angle of the alignment of tandem piers on local scour depth around them is investigated. The tandem piers were aligned with different skew-angles of θ=0°,30°,45°,60°,90° with respect to the flow direction. The results indicatethat with the increment of the skew-angle, the influence of sheltering effects is decreased. In other word, since the sheltering effect of the upstream pier is declined (which reduces the approach velocity for the downstream pier) the scour depth around downstream pier increases. The results show that the maximum scour depth occurs at both piers for the skew-angle of θ=45°.Furthermore, the best configuration to aligned tandem piers was achieved at the skew-angle of θ=30°.
43
Meng, Wen Yuan, Jia Qing Li, Ying Kui Guo, Guan Chao Xu, and Jun Wei Guo. "The Impact on the Pier of Shaped Charge Ice-Breaking and Numerical Simulation Analysis." Applied Mechanics and Materials 501-504 (January 2014): 1883–87. http://dx.doi.org/10.4028/www.scientific.net/amm.501-504.1883.
Full textAbstract:
In the process of shaped charge ice-breaking , the response of piers is great under the impact of air, ice, water etc, and relates to integral security of the bridge. For the impact on the pier with burst points of the different distances is simulated by ANSYS / DYNA software, summarizes the impact on the pier of shaped charge ice-breaking, and obtains the maximum stress curves of the pier at different distances. Simultaneously, the paper analyses critical damaging- model of the C30 reinforced concrete piers in detail. The conclusion has a major role in guiding when shaped charge ice-breaking appears.
44
Naser, Ali Fadhil, Hussam Ali Mohammed, and Ayad Ali Mohammed. "Mathematical Modeling of Linear Static and Dynamic Analysis for Pier Height Effect on the Structural Performance of Bridges Structures." Mathematical Modelling of Engineering Problems 8, no. 4 (August 31, 2021): 617–25. http://dx.doi.org/10.18280/mmep.080415.
Full textAbstract:
The results of linear static analysis explained that the increasing of pier heights was leaded to rise the values of positive bending moment, tensile stresses, and downward vertical deflection. Whereas the compressive stresses and negative bending moment were decreased, indicating that the structural performance of bridge structure representing by stiffness, bearing capacity of structural members, and elasticity will decrease and the bridges structures will be damaged. Therefore, the bridges structures need safe design when using tall piers by adopting high quality materials such as high strength concrete, more steel reinforcement, more prestressed tendons, and increasing of cross section dimensions of girders and piers. The results of modal analysis show that the un-loaded dynamic frequency for three types of bridges models were decreased when the pier heights were increased, indicating that the stiffness of bridges structure was became low with higher pier height. According to response spectra and time history analysis results, the loaded dynamic frequency (vibration state) and dynamic displacement were increased when the pier heights were increased, showing that the bridge of structure will suffer from high vibration when the pier height was high. It can be concluded that from this study, the piers heights have significant effects on the static and dynamic structural performance of bridges structures under traffic loads.
45
Wang, Zi Jian, Li Ming Wu, and Sheng Xie Xiao. "Vibration Response Analysis on Deep-Water Piers under Earthquake and Wave Coupling Motivation." Applied Mechanics and Materials 548-549 (April 2014): 1607–12. http://dx.doi.org/10.4028/www.scientific.net/amm.548-549.1607.
Full textAbstract:
Taking a typical cylindrical solid pier as example, this paper utilizes the way of additional mass to consider the influences of hydrodynamic pressure on piers. It establishes dynamic response comparative analysis of single pier model under different earthquakes’ motivation taking ANSYS finite element software as computing platform. This draws conclusion that hydrodynamic pressure keeps characteristics of changing the seismic response of piers in which pier top displacement and pier bottom internal force are increased. Also it acquires the conclusion that weight and cycle of structure are related to the effect of hydrodynamic pressure. Through analyzing continuous beam bridge and continuous rigid-frame bridge, it is verified that there exists close relationship between effect of hydrodynamic pressure and inherent cycle of structure in which the higher inherent cycle becomes, the lower influence hydrodynamic pressure keeps on structure.
46
Lu, Wenliang, Wen-Qiang Peng, Li Zhu, Cong Gao, Ya-Dong Tang, Yue-Wu Zhou, Wei Su, and Bing Zeng. "Experimental and Numerical Study of Static Behavior of Precast Segmental Hollow Bridge Piers." Materials 15, no. 19 (October 9, 2022): 6991. http://dx.doi.org/10.3390/ma15196991.
Full textAbstract:
To investigate the static performance of precast segmental hollow piers, two precast segmental hollow pier specimens were designed for static loading tests on the top of piers. The finite element model of precast segmental hollow piers was established by the finite element software Abaqus and verified based on the test results. Based on the experimental and finite element models, three optimal design solutions were proposed, and the calculation results of each solution were analyzed. The results show that precast segmental hollow pier mechanical behavior is similar to that of cantilevered bending members. The specimens present brittle damage characteristics after the destruction of the structure at the bottom of the pier pressure edge as the axis of the rigid body rotation. Following the test loading process, the bonding between the segments is good, except for the pier bottom damage surface of the rest of the bonding surface, which has no relative displacement. The calculation results of the finite element model are in good agreement with the test results and can effectively predict the load–displacement response of precast piers. Three optimized design solutions are proposed. The finite element simulation proves all three optimized design solutions show better overall ductility than the original solution and can effectively improve the performance of segmental precast hollow piers.
47
Ahmad, N., T. Mohamed, F. H. Ali, and B. Yusuf. "Clear-water local scour at wide piers in shallow-water flow." Water Practice and Technology 9, no. 3 (September 1, 2014): 331–43. http://dx.doi.org/10.2166/wpt.2014.035.
Full textAbstract:
Laboratory data for local scour depth regarding the size of wide piers are presented. Clear water scour tests were performed for various pier widths (0.06, 0.076, 0.102, 0.14 and 0.165 m), two types of pier shapes (circular and rectangular) and two types of uniform cohesionless bed sediment (d50 = 0.23 and d50 = 0.80 mm). New data are presented and used to demonstrate the effects of pier width, pier shape and sediment size on scour depth. The influence of equilibrium time (te) on scouring processes is also discussed. Equilibrium scour depths were found to decrease with increasing values of b/d50. The temporal development of equilibrium local scour depth with new laboratory data is demonstrated for flow intensity V/Vc = 0.95. On the other hand, the results of scour mechanism have shown a significant relationship between normalized volume of scoured and deposited with pier width, b. The experimental data obtained in this study and data available from the literature for wide piers are used to evaluate predictions of existing methods.
48
Chen, Libo, Yi Tu, and Leqia He. "A Probabilistic Capacity Model and Seismic Vulnerability Analysis of Wall Pier Bridges." Applied Sciences 10, no. 3 (January 31, 2020): 926. http://dx.doi.org/10.3390/app10030926.
Full textAbstract:
This study aims to establish a probabilistic capacity model of a wall pier under various damage states, and the seismic vulnerability of a typical wall pier bridge is studied. The finite element analysis of the wall pier is carried out by using the layered shell element, and its accuracy is verified through the comparison with the experimental results. A series of wall pier samples are generated based on the survey data, and the corresponding finite element models are established. The hysteresis analysis is implemented to obtain the displacement drift ratio of each seismic performance point. A candidate capacity model with various factors is proposed, and the unknown parameters are estimated and filtered by the Bayesian method. One hundred and twenty bridge samples of a benchmark bridge are generated by considering the uncertainty of parameters, and the finite element models are established. The bridge samples and ground motions were matched by one-to-one correspondence for the nonlinear time history analysis, and seismic vulnerability models of bridge components and system are obtained. The results showed that the in-plane capacity of wall piers is mainly affected by axial compression ratio, shear span ratio, and vertical reinforcement ratio. The wall pier shows excellent behavior in the earthquakes. The capacity models of wall piers can be used for evaluating the damage states of wall piers, and obtaining the seismic vulnerability model of wall piers bridges to be used for future seismic risk assessment and retrofit prioritization.
49
Yang, Yifan, Bruce W. Melville, Graham H. Macky, and Asaad Y. Shamseldin. "Local Scour at Complex Bridge Piers in Close Proximity under Clear-Water and Live-Bed Flow Regime." Water 11, no. 8 (July 24, 2019): 1530. http://dx.doi.org/10.3390/w11081530.
Full textAbstract:
In this study, we investigated the characteristics of scour at complex bridge piers in close proximity. The experiments were performed under both clear-water and live-bed flow regimes. We compare our results with those for a single complex pier. Further, the performance of existing predictors is discussed. In this study, four typical pier arrangements were adopted, including side-by-side with aligned or 30° skewed flow, staggered, and tandem. The results show that the skew angle for a side-by-side arrangement significantly accelerates the clear-water scour development at all the vertical piles as well as between the piers, and the most scoured pile shifts from the upstream end to the downstream end of the upstream pier flank. The staggered and tandem pier arrangement show significant protection to the downstream pier for both the developing rate and the equilibrium scour depth. When the flow velocity exceeds the threshold for general bed motion, the clear-water scour pattern for all the pier arrangements may be altered significantly due to the upstream sediment supply, the weakened protection effect, and the enhanced flow contraction. The bed-forms migrate via the bridge opening and are damped gradually by the flow, and thus the response of the bed morphology under live-bed conditions is quite unsteady.
50
Peng, Tianbo, and Ning Guo. "Applicability of a Simplified SDOF Method in Longitudinal Deck-Pier Poundings of Simply Supported Girder Bridges." Shock and Vibration 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/3569674.
Full textAbstract:
The pounding issue between decks in the earthquake has been a great concern of many researchers, but the research on the deck-pier pounding issue was inadequate. In this paper, a simplified SDOF method was proposed to study the issue for simply supported girder bridges. Theoretical analysis, shaking table test, and finite element analysis were conducted to study the applicability of the simplified SDOF method in longitudinal deck-pier poundings. A whole structural model and a SDOF model for the longitudinal pounding issue were also established to study influences of the pier stiffness and the pier mass on longitudinal pounding responses. It is shown that the simplified SDOF method can estimate the pounding force and deck displacement fairly accurately for almost all cases. The pier mass has little effect on pounding responses except for bridges with very rigid piers, but the pier stiffness has a great influence. The larger the pier stiffness is, the higher the peak pounding force is.