Journal articles: 'Uplift foundation capacity'

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Chen, Rong, He Feng Liu, Dong Xue Hao, and Zhi Yun Wang. "Comparative Analysis of Bearing Capacity of Inclined and Vertical Excavated Foundation." Applied Mechanics and Materials 680 (October 2014): 241–44. http://dx.doi.org/10.4028/www.scientific.net/amm.680.241.

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Excavated foundation has widely used in the field of transmission line engineering because of its large capacity to resist uplift and moment force. Elastic-plastic numerical model were established by using the finite element software ABAQUS focusing on the difference of bearing characteristics of inclined and vertical excavated foundation. There is very slight difference of axial uplift resistances between the both foundations because almost the same soil mass are mobilized at the same displacement loading. However, failure modes and horizontal resistances of negative, positive and vertical foundations are very different. The larger soil mass along the shaft of negative foundation is mobilized than positive and vertical foundations. The uplift resistances of vertical and negative foundations are about 5% and 25% higher than positive foundation at horizontal displacement of 50mm respectively.

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Xu, Lin, Yi Wan, and Peng Peng Jiang. "Calculation of the Effective Value of the Uplift Depth for the Tower Foundation in Sloping Ground." Applied Mechanics and Materials 496-500 (January 2014): 551–56. http://dx.doi.org/10.4028/www.scientific.net/amm.496-500.551.

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Uplift capacity is the main design control parameter of tower foundations. There are many factors to be considered in the design of tower foundations, such as the choice of models and the combination of different factors. The research on the uplift capacity of tower foundation is mainly focused on the foundations built on flat ground, while there is no mature method for the tower foundations placed in sloping ground. Base on the theory of earth pressure and the Mohr Coulomb law, This paper tries to establish the equations to calculate the uplift capacity of tower foundation placed in sloping ground and get the equation to obtain the effective value of the uplift depth for the tower foundation. At the end of the paper, a calculation example is presented using the simplified equation.

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Li, Xiaojun, Christophe Gaudin, Yinghui Tian, and Mark J. Cassidy. "Effect of perforations on uplift capacity of skirted foundations on clay." Canadian Geotechnical Journal 51, no. 3 (March 2014): 322–31. http://dx.doi.org/10.1139/cgj-2013-0110.

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The retrieval of deep water subsea installations resting on soft soil, such as “mudmat” shallow foundations, can be a difficult and costly operation if significant resistance to uplift is experienced. At the mudmat invert, suctions may develop, increasing the uplift resistance to greater than the weight of the mat. In this paper, a series of centrifuge model tests are performed to determine the uplift resistance of rectangular mudmats resting on lightly overconsolidated kaolin clay. The study investigates the influence of perforation, in combination with skirt length and eccentric uplift, on the uplift resistance and suction generation at the foundation invert. The outcomes demonstrate that the central and eccentric uplift of mudmats have different failure mechanisms, resulting in a different distribution of excess pore pressure at the foundation invert. In contrast, perforations do not change the failure mechanism and only alter the magnitude of suction generated. The two different configurations of perforation investigated significantly reduce the suction at the mat invert and the uplift resistance, and may potentially shorten the operating time for centred uplift. The combination of perforation and eccentric uplift has the most beneficial effect on the reduction of the uplift resistance.

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Mana, Divya S. K., Susan Gourvenec, and Mark F. Randolph. "Experimental investigation of reverse end bearing of offshore shallow foundations." Canadian Geotechnical Journal 50, no. 10 (October 2013): 1022–33. http://dx.doi.org/10.1139/cgj-2012-0428.

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Shallow skirted foundations can mobilize uplift resistance from end bearing in the short to medium term. However, uncertainty exists over the magnitude of reverse end bearing resistance compared with resistance in compression, and how this might be affected by a gap between the external face of the foundation skirt and the adjacent soil. The study presented in this paper explores this problem through centrifuge model tests, investigating the effect of skirt embedment ratio on (i) the magnitude of reverse end bearing capacity compared with compression capacity, (ii) the uplift displacement associated with spontaneous loss of suction during uplift, and (iii) the existence of a vertical gap along the external skirt–soil interface. The results show that (i) peak uplift capacity equivalent to compression capacity can be mobilized for a fully sealed foundation with an intact skirt–soil interface, (ii) suction required for reverse end bearing can be maintained through considerable foundation displacement, even for a low skirt embedment ratio, and (iii) the presence of a vertical gap along the external skirt–soil interface causes abrupt loss of suction beneath the top plate after minimal foundation displacement, with subsequent uplift capacity being markedly reduced.

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Yun, Sung Wook, 성욱 윤, Man Kwon Choi, Si Young Lee, Dong Hyeon Kang, Sung Dong Moon, Chan Yu, et al. "Uplift Capacity of Shallow Foundation for Greenhouse." Protected Horticulture and Plant Factory 24, no. 3 (September 1, 2015): 187–95. http://dx.doi.org/10.12791/ksbec.2015.24.3.187.

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Kumar, Pradeep, Mohit Kumar, V. K. Chandaluri, and V. A. Sawant. "Uplift Capacity of Single And Group of Granular Anchor Pile System." Journal of Civil Engineering, Science and Technology 9, no. 1 (April 30, 2018): 34–40. http://dx.doi.org/10.33736/jcest.879.2018.

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In view of increased development in the infrastructure across the world, now it becomes necessary to go for the marginal sites having weak soil for foundation. Foundations are normally designed to transfer compressive and uplift forces safely to the subsoil, wherein piles provide an appropriate solution. But the option of pile foundation is quite expensive. Before going for pile foundation, the feasibility of other alternatives must be accessed thoroughly. If it is possible to adopt some suitable ground improvement technique for enhancement of foundation strength, then it should be considered. In the present study, Granular Anchor Pile System is proposed to with stand uplift forces. The present paper, based on a field study, briefly discusses the basic principles associated with the granular pile. The analysis of field test data indicates that the proposed granular pile system is a viable means for ground improvement. It is found effective for improving varying soil conditions and capable of providing resistance to compressive forces in addition to the uplift resistance. Besides, this foundation technique has been found cost effective as compared to the concrete piles.

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Lu, Xian Long, and Qiang Cui. "The Bearing Capacity Character of Enlarged Base Shallow Foundation under Uplift Load." Advanced Materials Research 243-249 (May 2011): 2151–56. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.2151.

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By theory analysis and field tests, failure model of soil around foundation and ultimate uplift resistance of enlarged bass shallow foundation were analyzed. The results showed that the deformation and failure process of soil around foundation under uplift load undergone three phases: 1) soil upon enlarged base compressed, 2) appearance and extension of plastic zone of soil around foundation, and 3) soil around foundation general shear failure. With the combination of the Limit Equilibrium Method, and Sliding Curve Theory, a simplified theory model to calculate net ultimate uplift resistance of shallow foundation assuming cir failure surface under uplift load was established. Then three examples were calculated by this method and the good agreement between theory calculation solution and experimental results validated the rationality of the model. The study in this paper provided an important theoretical support and brand-new idea on calculation method of uplift capacity of foundation with enlarged base and failure surface characteristics determination of soil around foundation.

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Han, Yangchun, Jiulong Cheng, Qiang Cui, Qianyun Dong, and Wanting Song. "Uplift Bearing Capacity of Cone-Cylinder Foundation for Transmission Line in Frozen Soil Regions, Using Reduced-Scale Model Tests and Numerical Simulations." Energies 13, no. 8 (April 21, 2020): 2066. http://dx.doi.org/10.3390/en13082066.

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In order to analyze the uplift bearing capacity of cone-cylinder foundation for transmission line in frozen soil regions, a series of reduced-scale modeling tests and numerical simulations are carried out. First, three reduced-scale cone-cylinder foundations with the same sizes, that are five times smaller than the prototype, are made and then loaded under uplift load at −5 °C, −10 °C, and −15 °C, respectively. On this basis, the foundations of nine sizes are modeled and loaded by numerical simulation. The impact of three dimension factors, including the ratio of depth to bottom width ( λ = h t / D t ), the top diameter of the cone-cylinder (d), and the bottom diameter of the cone-cylinder (D), on the uplift bearing capacity of foundations have been investigated. The results reveal that, for cone-cylinder foundation, the uplift bearing capacity is obviously affected by the freezing temperatures and the foundation sizes. The capacity is negatively correlated with the former. Whereas the order of correlation with the latter is as follows: λ, D, and d based on the comprehensive results of range and variance analysis, but none of them are the significant factors, according to the F-test. Furthermore, three failure mechanisms of frozen soil are distinguished and named T-mode, V-mode, and U-mode, respectively. Based on the above results, the bearing mechanism of cone-cylinder foundation in frozen soil is elaborated in detail.

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Hao, Dong Xue, Yu Cong Gao, and Rong Chen. "Estimation of Uplift Capacity of Excavated Foundation of Transmission Lines." Applied Mechanics and Materials 680 (October 2014): 361–64. http://dx.doi.org/10.4028/www.scientific.net/amm.680.361.

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Finite element model for the system of foundation and its surrounding homogeneous soil is established based on software ABAQUS to analyze the uplift behavior of excavated foundation of transmission lines. The influence of soil properties and embedment ratio were analyzed. Deep mode occurs when embedment ratio is more than 4. As for shallow mode, the shearing method based on cylinder sliding surface was used to estimate uplift capacity. The expression of nominal uplift coefficient of earth pressure Ku in the formula was determined via back-calculation and fitting, which is the function of embedment ratio, friction angle and cohesion simultaneously. The errors of uplift capacity from fitting formula and numerical analysis are all within 15%.

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Harris, Daniel Edward, and Gopal Santana Phani Madabhushi. "Uplift capacity of an under-reamed pile foundation." Proceedings of the Institution of Civil Engineers - Geotechnical Engineering 168, no. 6 (December 2015): 526–38. http://dx.doi.org/10.1680/jgeen.14.00154.

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Yun, Sung Wook, 성욱 윤, Man Kwon Choi, Si Young Lee, Chan Yu, Yong Cheol Yoon, 만권 최, 시영 이, 찬. 유, and 용철 윤. "Uplift Capacity of Wood Pile for Greenhouse Foundation." Protected Horticulture and Plant Factory 24, no. 2 (June 1, 2015): 123–27. http://dx.doi.org/10.12791/ksbec.2015.24.2.123.

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Kumar, B. R. Phani, and N. Ramachandra Rao. "Increasing pull-out capacity of granular pile anchors in expansive soils using base geosynthetics." Canadian Geotechnical Journal 37, no. 4 (August 1, 2000): 870–81. http://dx.doi.org/10.1139/t00-012.

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Granular pile anchors are innovative and effective in resisting the uplift pressure exerted on the foundation by a swelling expansive soil. In a granular pile anchor, the foundation is anchored at the bottom of the granular pile to an anchor plate with the help of a mild steel rod. This renders the granular pile tension-resistant and enables it to offer resistance to the uplift force exerted on the foundation by the swelling soil. This resistance to uplift or pull-out load depends mainly upon the shear parameters of the pile-soil interface and the lateral swelling pressure of the soil, which confines the pile radially and prevents it from being uplifted. The resistance to uplift can be increased by placing a base geosynthetic above the anchor plate so that it forms an integral part of the granular pile anchor. The increase in resistance is due to the friction mobilized between the geosynthetic and the confining media when the uplift load acts on the pile and the geosynthetic moves along with the pile. Hence it depends on the friction between the geosynthetic and the confining media and the area and stiffness of the geosynthetic. This paper discusses the effects of these parameters on pull-out load, rate of heave, and relative ground movement near the pile surface.Key words: expansive soil, granular pile anchor, base geosynthetic, ground movement, rate of heave, pull-out load.

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Fan, Qing Lai, Mao Tian Luan, and Rong Chen. "Shape Effects on the Undrained Uplift Capacity of Skirted Suction Foundations in Clay." Applied Mechanics and Materials 353-356 (August 2013): 329–32. http://dx.doi.org/10.4028/www.scientific.net/amm.353-356.329.

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Skirted suction foundations are an attractive solution for floating offshore wind turbines that are subject to uplift due to overturning or buoyancy loading. Current industry design guidelines give conservative collapse loads for offshore shallow foundation systems, particularly due to neglecting the beneficial effect of suction developed within the soil plug during rapid uplift. The behavior of skirted rectangular and circular footings subjected to uplift loading has been studied using centrifuge model tests and upper bound plastic limit analyses. Results demonstrate that the shape effects on the uplift capacity factor are not significant when the circular and rectangular footings both obey reverse end bearing failure mechanism. Simple predictive methods based on existing bearing capacity theory are provided.

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Zhang, Yan, and Wei Feng Zheng. "Experiment Research of Rock Anchor Foundation on Sandstone Ground in Transmission Line." Applied Mechanics and Materials 580-583 (July 2014): 601–5. http://dx.doi.org/10.4028/www.scientific.net/amm.580-583.601.

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Rock anchor foundation can be widely used for the practical transmission line engineering in mountain areas. On strong-weathered sandstone ground, ten sets of uplift static load test of single rock anchor foundation were carried out. Based on the testing results, the typical failure modes and the ultimate uplift bearing capacity of foundations were obtained. Internal force distribution and effective anchorage depth were investigated through stain measurements. Design parameters of rock anchor foundation on sandstone ground were proposed, which can provide a reference for transmission line engineering design.

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Ding, Shijun, Yongfeng Cheng, Hong Zheng, Feng Xue, Zhibao Nie, and Yin Man. "Uplift Bearing Capacity of Transmission Tower Foundation in Reinforced Aeolian Sand Using Simplified Model Tests." Advances in Civil Engineering 2021 (July 23, 2021): 1–13. http://dx.doi.org/10.1155/2021/6630731.

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In order to analyze the uplift bearing capacity of transmission tower foundation in the geosythetic-reinforced aeolian sand, a series of simplified indoor modeling tests are carried out. A simplified reduced-scale foundation made according to the prototype and the uplift bearing capacity of transmission tower foundation in geosynthetic-reinforced aeolian sand is studied. Three kinds of reinforcement materials are embedded in the sand according to five ways of layout spacing. A total of 15 reinforcement schemes are tested. The results show that ultimate uplift bearing capacity of transmission tower foundation can be significantly improved by the reinforcement treatment of geotechnical materials in the aeolian sand. The type and spacing of reinforced materials also have a significant influence on the uplift bearing capacity of the foundation model in reinforced aeolian sand, and the effect of reinforcement works until the end of the loading process. The comprehensive effect is evaluated by the ratio of bearing capacity improvement and the total layer of reinforced materials. Based on the above results, the bearing mechanism of transmission tower foundation in geosynthetic-reinforced aeolian sand is elaborated and analyzed in detail.

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Dickin, E. A., and C. F. Leung. "The influence of foundation geometry on the uplift behaviour of piles with enlarged bases." Canadian Geotechnical Journal 29, no. 3 (June 1, 1992): 498–505. http://dx.doi.org/10.1139/t92-054.

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Centrifugal model tests investigating the influence of shaft to base diameter ratio and bell angle on the uplift capacity of piles with enlarged bases (or belled piers) in sand are reported. Increases in the angle of bell and in diameter ratio both result in a decrease in net uplift capacity and failure displacement. This appears to account for observed differences in uplift capacity between belled piers and anchor slabs. Studies of failure mechanisms around models of belled piers and anchor plates show distinctly different behaviour characteristics between foundation types. The comparatively low uplift capacities observed for belled piers are attributed to a lesser degree of soil mobilization. An empirical design method for belled piers is proposed in which appropriate factors which account for foundation geometry are applied to a simple continuous anchor formula. Key words : piles, sand, uplift capacity, centrifuge, design.

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Choi, Man Kwon, 만권 최, Sung Wook Yun, Ha Neul Kim, Si Young Lee, Chan Yu, Yong Cheol Yoon, et al. "Uplift Capacity of Pipe Foundation for Single-span Greenhouse." Protected Horticulture and Plant Factory 24, no. 2 (June 1, 2015): 69–78. http://dx.doi.org/10.12791/ksbec.2015.24.2.069.

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Qin, Li, Jin Xin Zhu, and Si Wen Zhao. "Research on Application of Suction Bucket Foundation for Transmission Tower in River Network Area." Advanced Materials Research 919-921 (April 2014): 727–30. http://dx.doi.org/10.4028/www.scientific.net/amr.919-921.727.

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Because the suction bucket foundation is construction period and low cost advantages,application of suction bucket foundation is more and more widely. In this paper, whether the suction bucket foundation can be used as the basis of transmission tower in river area were studied.According to the working mechanism of bucket foundation in soft clay ground and characteristics, through ABAQUS finite element simulation, bearing capacity under the pressure and uplift ultimate draw suction bucket foundation, and compare with the experimental results, verify the feasibility and accuracy of simulation.According to the transmission requirements of bearing capacity of the foundations,design the basic size,and verify whether the requirements of bearing capacity of foundation, confirmed the suction bucket foundation can be applied to the area of river network transmission tower.

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Xu, Jian, Jianwei Ren, Songhe Wang, Long Jin, and Jun Yuan. "Axial Uplift Behaviour of Belled Piers in Coarse-Grained Saline Soils." Advances in Civil Engineering 2018 (November 4, 2018): 1–16. http://dx.doi.org/10.1155/2018/4735423.

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Bearing capacity of belled pier foundation is critical in designing transmission lines in coarse saline soil region. This paper describes model test results on belled pier foundations. Axial uplift behaviours including failure modes, load-displacement curves, and ultimate uplift bearing capacity were discussed. The failure planes in four cases were obtained from pulled out cone-shaped bodies. An empirical equation was developed with a critical parameter of an uplift angle in design. Results indicate the range where the ground uplift shows circular extension at higher loads and the overall shear failure finally occurred. The load-displacement curves are primarily softening, and the uplift bearing capacity for coarse-grained saline soils (CSS) in the crystalline state increases at larger thickness, higher than that in dissolved state. Failure planes all exhibit approximately linear change from bottom to up. The angles of uplift for soils in crystalline and dissolved states can be taken as 34° and 18°, while 32° for the conventional for the sake of safety. Uplift behaviour of belled piers in CSS was modelled incorporating a practical interface model, with both failure planes and plastic range.

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Feng, Shi Lun, Hai Feng Jin, Jun Li, and Pu Lin Li. "Numerical Analysis of the Pit Excavation Influence on Foundation Piles." Applied Mechanics and Materials 99-100 (September 2011): 1239–42. http://dx.doi.org/10.4028/www.scientific.net/amm.99-100.1239.

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Excavation of the soil is actually the unloading process. The unloading process of soil makes the soil uplift, and the soil uplift is restricted by the pit engineering piles. And then, engineering piles should bear the vertical upwards pulling force caused by soil uplift. When pulling force is huge and tensile bearing capacity of pile is low, engineering piles could be pulled apart, and it is harmful to bearing capacity and durability of engineering piles. This paper adopts the finite element method to simulate engineering piles during pit excavation, and studies the traits of engineering piles in various excavation working conditions and different position. The computational results show that the deeper pit, the bigger displacement and tensile forces of piles, and the farther away from edges of the pit, the bigger displacement and forces of piles. In addition, the paper also gives a formula about the relationship between depth of pit excavation and uplift force on piles.

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Cui, Yu, and Jun Qiang Wu. "The Vertical Bearing Capacity Analysis of Screw Pile in Clay." Advanced Materials Research 788 (September 2013): 575–77. http://dx.doi.org/10.4028/www.scientific.net/amr.788.575.

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Recently,ocean energy, especially wind energy, gains attention from all over the world.In offshore engineering , the design and construction of foundation are key factors. As a new type of piles, screw pile has advantages of compressive capacity and uplift capacity.Therefore, screw pile is a good choice for offshore engineering foundation. In this paper , ABAQUS software analysed vertical bearing capacity of screw pile and steel pile with same diameter in clay .And the analysis result shows : the compressive resistance and uplift resistance of screw pile are 1104KN and 974.3KN, the same capacity of steel pile are only 332.3KN and 189.7KN.

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K S, Yogesh. "Strength & Stability Analysis of Straight Shafted Pile Foundation in Cohesive Soil Condition using Finite Element Analysis." International Journal for Research in Applied Science and Engineering Technology 9, no. VII (July 31, 2021): 3612–17. http://dx.doi.org/10.22214/ijraset.2021.37194.

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Pile foundation is one of the effective forms of deep foundation. This is to be used where the load has to be transferred to deeper layers of soil and it can with stand uplift forces in foundations in expansive soil and also in case of floating foundations. The finite element method is one of the most versatile and comprehensive numerical technique which can be used for analysis of structures or solids of complex shapes and complicated boundary conditions. There are different variables which influence the load carrying capacity of pile foundation. But only some of those have significant influence on load carrying capacity. Here those variables are considered and the variation of load carrying capacity with the change in value of those variables is observed. Those variables are pile length and pile diameter, analysis of pile foundation was carried out to determine the ultimate load carrying capacity of pile for different lengths and diameters in cohesive soil, the corresponding settlement was also determined.

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Armaghani, Danial Jahed, Houman Sohaei, Eshagh Namazi, and Aminaton Marto. "Investigation of Uplift Capacity of Deep Foundation in Various Geometry Conditions." Open Construction and Building Technology Journal 13, no. 1 (December 31, 2019): 344–52. http://dx.doi.org/10.2174/1874836801913010344.

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Background: Uplift resistance of deep foundations or piles is a critical factor for deep foundation design in several civil engineering applications such as electric transmission towers, communication towers and wind power generators. Therefore, the behavior of the pile under uplift load, together with its influential parameters, should be studied to provide a proper design. Objective: The aim of this study was to identify the effects of pile geometry, including diameter and embedment depth on the Maximum Uplift Resistance (MUR) of the small-scale piles. Methods: To achieve the aims of this study, a total of nine laboratory experiments having various pile diameters (i.e. 9 mm, 12 mm and 15 mm) and embedment depths (i.e., 10 cm, 15 cm and 20 cm) were planned, designed and conducted. Results: Generally, the results indicated that both diameter and embedment depth have a significant effect on the MUR of piles. The values of the MUR of piles were increased by increasing the pile diameters in all conducted tests. Furthermore, a significant increase in the MUR results was observed when the embedment depths are increased from 10 cm to 20 cm. Moreover, in all cases, small-scale piles were failed in embedment depths ranging from 5 mm to 10 mm. Conclusion: It was concluded that pile geometry has a deep impact on the MUR of the piles. Future research can be done to investigate the effects of other influential factors on the MUR.

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Li, Yuanqi, Xiaoliang Qin, Jinhui Luo, Meng Xiao, and Cong Hua. "Uplift Test and Design Method for Bearing Capacity of Isolated Spread Concrete Foundation Slab with Large Width-to-Height Ratio." Advances in Civil Engineering 2018 (November 15, 2018): 1–16. http://dx.doi.org/10.1155/2018/3672868.

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This paper is focused on the experimental study and numerical simulation of isolated spread concrete foundation slab with a large width-to-height ratio (in short ISCFS-LWR) to investigate the failure modes and uplift bearing capacity, as well as the design method of uplift capacity. First, a total of 16 isolated spread concrete foundation slabs with the width-to-height ratio varied from 1.5 to 4 and the hypotenuse slope varied from 10° to 30° were tested under uplift load. Based on the test results, effects of the width-to-height ratio and the hypotenuse slope on uplift bearing capacity of ISCFS-LWR were analyzed and discussed. Then, several numerical models were built using the finite element software ABAQUS and the results of numerical analysis agreed well with the test results. Furthermore, the cross-sectional performance of ISCFS-LWR was studied, and the coefficients of internal force arm were also evaluated further using previous validated numerical models. To obtain the suggested design method of uplift capacity for the foundation slab, effective width correction coefficient k and slope correction coefficient j were introduced to propose a design formula. Finally, the proposed design method was applied to a practical engineering, and the economic indicators obtained from the suggested design method were compared with that from the original design method. The results of this paper showed that the correction coefficient jsks based on numerical analysis agreed well with the recommended correction coefficient jk, and the error was between 1% and 3.4%, by which the reasonability of the proposed design method of uplift capacity for ISCFS-LWR has been proved. It can also be found that the economic benefits of the practical engineering in this paper were obvious due to the suggested design method, and this paper can provide a reference for other engineering practices and the further research work on ISCFS-LWR.

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Kulczykowski, Marek. "Experimental Investigation of Skirted Foundation in Sand Subjected to Rapid Uplift." Archives of Hydro-Engineering and Environmental Mechanics 67, no. 1-4 (December 1, 2020): 17–34. http://dx.doi.org/10.1515/heem-2020-0002.

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Abstract This paper reports results from 1g model tests carried out under single gravity on a skirted foundation installed in sand and subjected to a rapid uplifting force. The effects of displacement rates ranging from 5 mm/s to 450 mm/s on the ultimate capacity, suction pressure inside the skirt compartment, and time of extraction were investigated. Test results indicate that the displacement rate significantly affected the magnitude of uplift resistance, as well as the magnitude of suction under the foundation lid, but had little effect on the relationship between stress and the displacement of the foundation. The shapes of the uplift capacity-displacement curve and the suction-displacement curve were similar for all experimental displacement rates.

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Wang, Zhi Yun, Mao Tian Luan, and Lu Shen. "Bearing Capacity of Suction Caisson Foundations Using FEM Analysis." Advanced Materials Research 243-249 (May 2011): 2112–15. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.2112.

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To understand features of bearing capacity of suction caisson foundation is one of the key issues in design and construction of deep-water marine structures. In this paper, the general-purpose finite element analysis package ABAQUS is employed to conduct three-dimensional numerical analyses on load-carrying features of suction caisson foundation under vertically uplift load, horizontal load and moment. Then the ultimate bearing capacity of suction caisson foundation for undrained condition of the soil is evaluated by displacing-controlling procedure. Moreover, three-dimensional failure envelope of suction caisson foundation under combine loading condition are established by the proposed numerical procedure.

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Yun, Sung-Wook, Man Kwon Choi, Si Young Lee, and Yong Cheol Yoon. "Uplift Capacity of Continuous Pipe Foundation for Prevention of Meteorological Disaster." Journal of Agriculture & Life Science 49, no. 5 (October 30, 2015): 303–10. http://dx.doi.org/10.14397/jals.2015.49.5.303.

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Hao, Dongxue, Rong Chen, and Guangsen Fan. "Ultimate Uplift Capacity of Transmission Tower Foundation in Undisturbed Excavated Soil." Energy Procedia 17 (2012): 1209–16. http://dx.doi.org/10.1016/j.egypro.2012.02.228.

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Shengxi, Su, Ding Jihui, and Yan Meng. "Comparative Analysis of the Compression and Uplift Bearing Characteristics of PHC Pipe Pile on the Same Site." Open Civil Engineering Journal 14, no. 1 (March 20, 2020): 31–43. http://dx.doi.org/10.2174/1874149502014010031.

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Introduction: The analysis of single pile behavior is an important foundation for the analysis of group pile foundation and other complex pile foundations. Methods: Based on the analysis of the load transfer of the compression pile and the uplift pile, the DoseResp model is used to fit the normalized load transfer function. Results: The results show that the load transfer function of the uplift pile and the compression pile has similar characteristics, the goodness of fit of the DoseResp model to the test data is greater than 0.99, which can better reflect the load transfer law of the pile. The fitting parameters in the DoseResp model mainly depend on the end resistance sharing ratio, A2 (Top asymptote)is independent of pile type and soil property parameters and is close to 1. The DoseResp model is applied to the PHC pipe pile, and the method to determine the parameters of the model fitting is proposed, which can accurately determine the side resistance distribution of PHC compression and uplift pipe pile along the pile body. Under the same load, the amount of uplift on the top of the uplift pile is significantly greater than the settlement on the top of the compression pile. Conclusion: The end resistance sharing ratio of the compression pile and the uplift pile is between 5.76 and 12.80. The ultimate bearing capacity of the compression pile is 3.61 ~ 3.81 times of that of the uplift pile under the same geometric parameters.

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Man, Yin, Xian Long Lu, and Wei Feng Zheng. "Experimental Study on Bearing Characteristics of the Pad and Chimney Foundation in Salt Lake Area." Applied Mechanics and Materials 256-259 (December 2012): 97–100. http://dx.doi.org/10.4028/www.scientific.net/amm.256-259.97.

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Transmission line foundation engineering inevitably encounters the special geological conditions in salt lake area, such as strong corrosion of saline soil, weakness of foundation soil and high water table of groundwater. In-situ tests on bearing characteristics of the selected pad and chimney foundation were conducted. Ultimate uplift bearing capacity and ultimate compressive bearing capacity of the pad and chimney foundation in salt lake are obtained, which can verify the rationality and reliability for its engineering popularization.

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Ye, Chao Liang, Huai Ping Feng, and Yao Jun Liu. "In Situ Study on Reinforced Effect of Silt by Ram-Compaction Gravel Pile with End Expansion." Advanced Materials Research 446-449 (January 2012): 3428–31. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.3428.

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Ram-compaction gravel pile with end expansion is widely adopted in the treatment of silty clay foundations. In this paper, the bearing properties of rammed gravel pile reinforced foundations and soil between piles were investigated by use of static load tests and heavy-duty dynamic penetration test. It is demonstrated that the settlement curves (P-S curve) of ram-compaction gravel pile with end expansion reinforced foundation and soil between piles were monotonic, without turning point being observed. With the increases of pile length, the bearing capacity of pile increases. According to the experimental results from heavy dynamic penetration tests and static load test, the strength of soil between piles is improved, which also have effects on the elimination of the uneven settlements. Comparison the results between heavy-duty dynamic penetration tests and over-heavy dynamic penetration tests shows that the later one is suitable on testing of the soil properties between piles. In addition, from in-situ measurements of uplift deformation of different depths, it is found that uplift behavior occurs with depth more than 0.5m, whit largest uplift value of 21cm. The result provides a reference for the design and construction of rammed gravel pile reinforced foundation.

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32

Zhou, Kun, Linhua Chen, Xiangyu Gu, and Qi Zhang. "Research on Uplift Bearing Performance of Assembled Steel Pipe Pile used in Transmission Lines in Mountainous Terrain." MATEC Web of Conferences 275 (2019): 03008. http://dx.doi.org/10.1051/matecconf/201927503008.

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Assembled steel pipe pile, which is a novel pile foundation, is developed in the paper. The ultimate uplift bearing capacity of the pile is proposed, and simulation by Plaxis3D and the corresponding experiment are performed to verify the theory. In the simulation, ultimate uplift bearing capacity of the assembled steel pipe pile and ultimate lateral frictional resistance of the interface of pile-soil increases with the increasing of the strength and stiffness of the interface of pile-soil, and with the increasing of length-diameter ratio, ultimate uplift bearing capacity of the assembled steel pipe pile increases while the ultimate lateral frictional resistance decreases gradually. The ultimate lateral friction is influenced by both of the strength of the soil around the pile and the interface of pile-soil, and the ultimate uplift bearing capacity obtained by simulation and theoretical calculation are close. Long-gauge FBG sensors are used in the experiment for measuring the longitudinal strain of the pile, and the error of ultimate uplift bearing capacity between the results of experiment and theory is less than 10%.

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Chen, Kun, and Yu Bin Dou. "Study on Design of Uplift Piles According to the Elastic Foundation Beam Theory." Advanced Materials Research 838-841 (November 2013): 907–12. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.907.

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Taking the every arranged uplift pile in a practical project for example and selecting the column strip on the scale board as the research object, this paper analysis mainly focuses on the pullout capacity of piles at different locations with different vertical loads from columns by using the Winkler elastic foundation beam model. The results show that design with assumption that uplift piles evenly share the net buoyance would lead to successive failure of the piles. Then further parametric analysis was conducted to study the influence of stiffness, thickness and column space on the vertical forces of piles. The conclusions could provide positive reference to related uplift pile design.

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Richards, D. J., D. J. White, and B. M. Lehane. "Centrifuge modelling of the pushover failure of an electricity transmission tower." Canadian Geotechnical Journal 47, no. 4 (April 2010): 413–24. http://dx.doi.org/10.1139/t09-112.

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Centrifuge model tests were conducted to examine foundation failure mechanisms during rapid horizontal pushover of an electricity transmission line support tower, simulating a broken transmission line response or wind gust loading. A model transmission tower supported on four pad foundations in clay and backfilled with sand was loaded horizontally and the loads at each foundation were measured during fast and slow pushover. The tests examined the influence of tensile resistance mobilized at the underside of the footings, which is difficult to reliably incorporate within design practice due to a lack of accepted quantitative design methods. The measured performance of the tower footings was compared with results from a series of tests where a single footing is subjected to purely vertical loading in compression and tension and was found to be in good agreement. The tower response was back-analysed as a simple push–pull model and the calculated uplift capacity of the footing backfill provided a close match to the observed response of the tower footings subjected to slow pushover. During fast pushover, the additional capacity mobilized due to tensile resistance (suction) created by the reverse bearing capacity beneath the base of the footings subjected to uplift was quantified using a suction capacity factor.

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35

Yu, S. B., J. P. Hambleton, and Scott William Sloan. "Analysis of Inclined Strip Anchors in Sand Based on the Block Set Mechanism." Applied Mechanics and Materials 553 (May 2014): 422–27. http://dx.doi.org/10.4028/www.scientific.net/amm.553.422.

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Anchors are widely used in foundation systems for structures requiring uplift resistance. As demonstrated by numerous theoretical and experimental studies on the subject, uncertainty remains as to both the theoretical uplift capacity of anchors in idealised soils and the suitability of the various modelling assumptions in capturing the responses observed during tests. This study, which deals exclusively with the theoretical uplift capacity, presents newly obtained predictions of uplift capacities and the corresponding collapse mechanisms for inclined strip anchors in sand. The analysis is based on the upper bound (kinematic) method of limit analysis and the so-called block set mechanism, in which a collapse mechanism consisting of sliding rigid blocks is optimised with respect to interior angles and edges of the blocks. It is demonstrated that the method provides lower (better) estimates of uplift capacity in some cases compared to previous upper bound calculations. Also, variations in the predicted collapse mechanism with changes in embedment and inclination are assessed in detail.

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Wang, Zhi Yun, Yue Sun, and Chuan Cheng Wang. "Numerical Simulation of Ultimate Capacity of Suction Caisson Foundations by FEM." Applied Mechanics and Materials 170-173 (May 2012): 3478–81. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.3478.

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As a newly developed type of foundation for deep water offshore and marine engineering, the suction caisson is usually subjected to combined loading of vertically uplift load, horizontal load and moment. Performance evaluation and design theory for such a new type of foundation can not meet the basic requirements of engineering practice sufficiently at present. In this paper, the general-purpose finite element analysis package ABAQUS is employed to conduct three-dimensional numerical analyses on load-carrying features of suction caisson foundation. Then the ultimate bearing capacity of suction caisson foundation under monotonic load for two drainage conditions of the soil is evaluated by displacing-controlling procedure.

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YAMAKAWA, Yuki, Hiroki MIZOE, Yutaka CHIDA, Jo TODA, Kiyohiro IKEDA, Hiroshi TAMURA, and Kenjiro TERADA. "UPLIFT CAPACITY ANALYSIS OF ANCHOR FOUNDATION FOR TRANSMISSION TOWER ON SLOPE CREST." Journal of Japan Society of Civil Engineers, Ser. C (Geosphere Engineering) 71, no. 1 (2015): 1–13. http://dx.doi.org/10.2208/jscejge.71.1.

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Dai, Guo-liang, Wen-bo Zhu, Qian Zhai, Wei-ming Gong, and Xue-liang Zhao. "Upper Bound Solutions for Uplift Ultimate Bearing Capacity of Suction Caisson Foundation." China Ocean Engineering 33, no. 6 (December 2019): 685–93. http://dx.doi.org/10.1007/s13344-019-0066-9.

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Wang, Xing Yun, Bin Peng, Xiao Chao Tang, and Lian Fan. "Numerical Simulation for Uplift Bearing Capacity and Affecting Factors of the Digging Piles in Slope Ground." Applied Mechanics and Materials 423-426 (September 2013): 1292–95. http://dx.doi.org/10.4028/www.scientific.net/amm.423-426.1292.

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Based on the numerical simulation method, this paper has established the numerical simulation method by using of finite difference software of FLAC3D through establishing interface for digging pile-soil. It can consider mutual effect of digging pile-soil. The uplift bearing capacity of the digging pile in slope ground was calculated and the affecting factors of the bearing capacity were analyzed. The results show that the uplift bearing capacity has a negative correlation with the slope ratio, and has a positive correlation with the width or height of the foundation, which can be expressed as a quadratic polynomial. But when the slope ratio is smaller than a certain extent, the capacity no longer increases. Nonlinear regression analysis of calculation data are carried out. Finally, the calculation method of uplift bearing capacity about pile in the slope is developed, which can provide a reference to specification revision and engineering.

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Cui, Qiang, and Xian Long Lu. "Calculation Method on Bearing Capacity of Anchor Bolt of Transmission Line Tower Foundation Considering Influence of Horizontal Force." Applied Mechanics and Materials 170-173 (May 2012): 327–30. http://dx.doi.org/10.4028/www.scientific.net/amm.170-173.327.

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Anchor bolt which is one of the most important component connecting foundation and transmission tower bears the force transmitted from superstructure. At present, in the conventional design method, uplift force is only included, however, the influence of horizontal force on bearing capacity of anchor bolt is neglected. Thus, a theoretical method on obtaining bearing capacity of anchor bolt is proposed for the first time based on the third strength theory in this paper, in which the influence of horizontal force is considered. According to the third strength theory, the calculation results of bearing capacity of anchor bolt under different force are obtained. It can be seen that the cross-section area of single anchor bolt shows linear increase with the increment of vertical uplift force, at the same time, the influence of horizontal force to bearing capacity of anchor bolt is more significant with the addition of the ratio of horizontal force to uplift force, which should be attached enough attention in engineering application. And the conclusion achieved in this work can provide valuable guidance for anchor bolt design of the transmission line project.

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41

Saeedy, Hamed S. "Stability of circular vertical earth anchors." Canadian Geotechnical Journal 24, no. 3 (August 1, 1987): 452–56. http://dx.doi.org/10.1139/t87-056.

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This study aims to provide an extensive analytical approach for determining the uplift capacity of circular vertical earth anchors and to investigate the soil–anchor interaction. The solution is simplified by utilizing proper dimensionless parameters, in which controlling dimensionless factors [Formula: see text] are produced for a range of values of H/D and angle of internal friction. The factor [Formula: see text] is a pressure ratio representing gravitational and shear strength of the soil, and H/D signifies relative depth, which pertains to anchor geometry. The functional relationship of these parameters was previously studied for H/D ratios up to 6. The present work concludes that the greater the value of H/D the higher the uplift resistance, but with a decreasing rate until a constant value of uplift force is reached. The transitional value of depth, which defines the condition of failure, is a function of the shear strength of the burial soil. This transitional stage indicates the optimum possible value for uplift capacity for a given relative depth (H/D). Key words: tension foundation, uplift capacity, earth anchor load capacity, soil anchor interaction.

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42

Wallace, Jeff F., and Cassandra J. Rutherford. "Response of suction caissons for tidal current turbine applications in soft clay to monotonic and cyclic vertical loading." Canadian Geotechnical Journal 55, no. 4 (April 2018): 551–62. http://dx.doi.org/10.1139/cgj-2016-0133.

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In soft marine clays, suction caissons provide a foundation system for tidal current turbines that further promote the sustainable nature of the system by allowing for their removal at the end of the structure’s design life. When configured as a multipod, the moment loads resulting from the horizontal flow of water will be transferred to the suction caissons as compression–uplift loads on opposing foundation legs. The behavior of a suction caisson in soft clay was investigated at aspect ratios of 1 and 2 under monotonic and cyclic vertical loading applicable to multipod-supported tidal current turbine design. Installation and solely monotonic vertical load tests indicated lower back-calculated adhesion factor, α, values and higher back-calculated bearing capacity factor, Nc, values than design standards recommend. The capacity and stiffness response of the foundation after undergoing cyclic loading was found to be largely dependent on the magnitude of displacement the foundation underwent during cyclic loading. Additionally, a threshold of elastic foundation response was observed during cyclic loading defined by a cyclic displacement amplitude. These results indicate serviceability constraints will be critical in the design of suction caisson foundations for tidal current turbine applications.

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ACOSTA-MARTINEZ, H. E., S. GOURVENEC, and M. F. RANDOLPH. "Centrifuge study of capacity of a skirted foundation under eccentric transient and sustained uplift." Géotechnique 62, no. 4 (April 2012): 317–28. http://dx.doi.org/10.1680/geot.9.p.027.

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Feng, Xu, Xiaojian Pi, Shilun Feng, and Chen Bian. "Research on the Uplift Bearing Capacity of Suction Caisson Foundation under Local Tensile Failure." Procedia Engineering 166 (2016): 61–68. http://dx.doi.org/10.1016/j.proeng.2016.11.563.

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45

Lu, Xilin, Kunye Zhou, Maosong Huang, and Zheng Su. "Numerical modeling the uplift bearing capacity of transmission line tower foundation on expansive soil." Japanese Geotechnical Society Special Publication 7, no. 2 (April 30, 2019): 636–40. http://dx.doi.org/10.3208/jgssp.v07.097.

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46

Iekel, Philip P., Brent Phares, and Michael Nop. "Performance Investigation and Design of Pile-to-Pile Cap Connections Subject to Uplift." Transportation Research Record: Journal of the Transportation Research Board 2672, no. 52 (September 18, 2018): 278–90. http://dx.doi.org/10.1177/0361198118796733.

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Substructure bridge components are designed to resist gravitational forces such as dead load and vehicular live load, as well as lateral forces including wind, vehicular braking, and centrifugal force effects. Significant lateral forces can create “uplift” conditions on some portions of the foundation. A review of current design techniques regarding uplift in the pile-to-pile cap connection indicates a lack of uniformity in the design process across state agencies stemming from minimal research performed in this area. In addition, approved uplift anchors for use in the field have not been tested. In order to close this gap, twenty-one full-scale steel H-pile specimens were fabricated and tested in Iowa State University’s Structural Engineering Laboratory to test the capacity of the pile-to-pile cap connection under static tensile loading. Specimens were cast both with and without anchorage and with 12” and 24” embedment depths in order to understand the behavior of the connection and to determine a suitable anchorage detail and design approach for uplift cases. Findings revealed that: (i) capacity of bare piles is generally underestimated and could be more frequently considered for uplift design; (ii) concrete cracking leads to a loss of bond in these types of connections; and (iii) positive anchorage or embedment that extends above the lower rebar mat of the footing is necessary to develop a high capacity connection.

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47

Han, Yangchun, Jiulong Cheng, Weifeng Zheng, and Shijun Ding. "Estimating the Uplift Bearing Capacity of Belled Piers Adjacent to Sloping Ground by Numerical Modeling Based on Field Tests." Advances in Civil Engineering 2020 (January 25, 2020): 1–12. http://dx.doi.org/10.1155/2020/1647197.

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In order to evaluate the uplift bearing capacity of belled piers beside slopes, a series of numerical simulations are carried out based on field tests data. First, a number of uplift loading tests of full-scale belled piers are carried out on the project site of transmission line in Anhui Province, China. Second, a slope-foundation model for numerical modeling is proposed and calibrated based on field tests data. The behavior of belled piers adjacent to slopes subject to uplift load is studied by numerical modeling. The impact of three parameters, including distance (a) from the belled pier to the crest of the slope, slope angle (β), and embedment depth (h) of the belled pier, has been investigated on the uplift capacity of the belled pier. Based on the simulation results, an attenuation coefficient (ω) is put forward for evaluating the reduction of uplift bearing capacity of the belled pier. The results show that the coefficient ω is negatively correlated with distance a and depth h, and the influence of distance a is greater than that of depth h according to the results of variance analysis, but the difference is not significant by F test. Moreover, the empirical equation between attenuation coefficient ω and three key factors a, β, and h had been presented by a series of fitting.

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48

Yilmaz, M. Tolga, and B. Sadik Bakir. "Capacity of shallow foundations on saturated cohesionless soils under combined loading." Canadian Geotechnical Journal 46, no. 6 (June 2009): 639–49. http://dx.doi.org/10.1139/t09-013.

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Under seismically induced loading, shallow foundations commonly fail by overturning on saturated soils. While the excess pore pressures may have fully dissipated following construction, undrained conditions are typically presumed in the assessment of seismic capacity in conventional applications due to the high rates of loading induced during an earthquake. Undrained strength, however, can be critically dependent on the history of loading and significantly heterogeneous and anisotropic around a foundation. The finite element method is utilized in this study for a proper assessment of the impact of these factors on the overturning moment capacity of surficial foundations on saturated soils, with specific emphasis on failure under seismic loading. Uplift capability has been incorporated into the models and analyses have been conducted for different drainage conditions. Based on the analyses results and comparisons with analytical formulae, it is concluded that the assumption of homogeneous soil strength as well as the disregard of stress path followed can lead to significant overestimation of the overturning moment capacity. The proposed improved approach comprises calculation of the overturning moment capacity based on drained soil behavior and subsequent application of an undrained behavior reduction factor (URF) compatible with the representative pore-pressure parameter A.

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Zekavati, Ali-Asghar, Alireza Khodaverdian, Mohammad-Ali Jafari, and Ahmad Hosseini. "Investigating performance of micropiled raft in foundation of power transmission line towers in cohesive soil: experimental and numerical study." Canadian Geotechnical Journal 55, no. 3 (March 2018): 312–28. http://dx.doi.org/10.1139/cgj-2017-0027.

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This paper captures the behavior of micropiled rafts in power transmission line tower foundations in cohesive soil, concentrating on their uplift performance whether due to the tower position along the line or under wind loading conditions. In this regard, first a number of micropiles were driven into the ground of a project site at the ParehSar power plant, Gilan, Iran. Compression and uplift loading tests were conducted according to relevant standards. On the basis of the field data, a three-dimensional finite element model was developed and subsequently calibrated and verified. The behavior of micropiled rafts subjected to uplift, which is a typical type of loading in foundations of 230 kV four-circuit lattice towers, was then studied by means of this model in terms of a wide-ranging parametric study. In the sensitivity analyses, the impacts of various parameters, such as micropile spacing-to-diameter (s/d) and length-to-diameter (l/d) ratios along with undrained shear strength of the soil, on the uplift capacity of an individual micropile within and out of the group were investigated. Furthermore, interaction factors were computed based on diverse values for undrained shear strength of the soil, s/d ratio, l/d ratio, and grout–soil adhesion. From design and analysis perspectives, the finite element method (FEM) outputs revealed that the efficiency coefficient of micropiled rafts during uplift can be considered equal to one. Moreover, it was found that not only does the behavior of micropiles affect the neighboring micropiles immediately adjacent to the loaded one, but it also influences those in further rows, the result of which would be considering their significance as well.

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Filiatrault, A., D. L. Anderson, and R. H. DeVall. "Effect of weak foundation on the seismic response of core wall type buildings." Canadian Journal of Civil Engineering 19, no. 3 (June 1, 1992): 530–39. http://dx.doi.org/10.1139/l92-062.

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This paper investigates the seismic behaviour of a typical wall-type reinforced concrete building with a footing that is unable to develop the flexural wall capacity. Nonlinear dynamic analysis is used to determine the response of the structure under historical earthquakes representing design conditions for a seismic zone 4 in Canada. The analysis incorporates the nonlinear behaviour of the core, footing and soil, and also the uplift of the footing from the soil. Three different structural models are considered: (i) the core on a rigid foundation, (ii) the core on a flexible (rocking) foundation, and (iii) the core on a flexible foundation with the two lower levels connected to a parking structure. The results show that the weak footing does not have a great influence on the performance of the building considered. The parking structure and the rocking foundation cause a reversal and increase of the shear forces in the lower storeys. Also, the reduction of bending moments due to the core yielding is not proportional to the reduction of shear forces. This result suggests a need for different force modification factors for shear and bending. Key words: dynamics, earthquakes, reinforced concrete, building codes, foundations, footings.

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Journal articles on the topic 'Uplift foundation capacity'

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