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1
Hanna, A. M., and A. Afram. "Pull-out capacity of single batter piles in sand." Canadian Geotechnical Journal 23, no. 3 (1986): 387–92. http://dx.doi.org/10.1139/t86-054.
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The pull-out capacity of single rigid vertical and batter piles in sand and subjected to axial loading has been investigated. Good agreement was found when test results on instrumented model piles were compared with theoretical estimates. The effect of pile inclination on the pull-out capacity has been explained by means of variable mobilized passive earth pressure on the pile's perimeter. A design method and charts are presented. Key words: pile foundation, pull-out capacity, vertical pile, batter pile, sand–soil mechanics.
2
Zhou, Dequan, Qin Zhu, and Chuangye Wang. "Experimental Investigation on Performances of Battered Piles Resisting Embankment-Induced Lateral Soil Movement." Applied Sciences 13, no. 18 (2023): 10333. http://dx.doi.org/10.3390/app131810333.
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The performance of passive battered piles resisting the embankment-induced lateral soil movements may differ from that of the active battered pile and axially loaded existing vertical piles adjacent to embankment constructions. This study was part of a preliminary feasibility investigation for a reinforcement plan of an actual embankment project, aiming to experimentally investigate the performance of passive battered piles under embankment-induced lateral soil movement. To this end, a sequence of reduced-scale model tests of battered piles near the surcharges was first designed in sandy soil with a similarity ratio of 1:30. The effects of pile inclinations (β = −20°, −10°, 0°, +10°, and +20°), surcharge magnitudes, and constraint conditions at the pile tip (free-tip and fixed-tip) on the responses of passive battered piles were explored. Finally, the response characteristics of battered piles resisting the embankment-induced lateral soil movement were analyzed to clarify the working mechanism of these battered piles.
3
Ren, Xiang, Lijuan Luo, Yunxin Zheng, Jiakuan Ma, and Xuexu An. "Morphological Evolution of Passive Soil Arch in Front of Horizontal Piles in Three Dimensions." Buildings 12, no. 7 (2022): 1056. http://dx.doi.org/10.3390/buildings12071056.
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The anti-slide pile is a primary method of landslide control. The effect of the passive soil arch in front of the embedded section of piles has a significant effect on the anti-slide pile’s bearing capacity. The upgraded model test scheme was used to conduct model tests with a pile spacing four times the width of the pile and a geometric scale ratio of 1:15. The anti-slide pile stress, pile bending strain, and soil stress in front of the pile were all studied in relation to the loading amount. In addition to the model test, the numerical simulation method was utilized to investigate the three-dimensional morphological change of the passive soil arch in front of the pile. The results indicated that: clearly, the side piles can eliminate the border effect. The distribution of pile bending strain along the pile after loading is referred to as a parabola. Bending failure occurred at a depth of 40 mm, approximately 0.9 m from the pile top. Under the condition that the pile spacing is four times the pile width, a passive soil arch occurs in front of the anti-slide pile’s fixed part, and its development can be split into four stages: formation, development, completion, and destruction. The passive soil arches in front of the piles are generated and destroyed gradually along the buried depth, and the three-dimensional surface of the space drops gradually along the buried depth with the loading amount and advances toward the loading direction until the anti-slide pile system fails. The research findings and experiences can serve as a basis for future research.
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Zhang, Hao, Minglei Shi, Lei Yang, and Yuancheng Guo. "A Semianalytical Solution for Passively Loaded Piles Adjacent to Surcharge Load." Advances in Civil Engineering 2020 (June 10, 2020): 1–19. http://dx.doi.org/10.1155/2020/2398389.
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Piles adjacent to a surcharge load commonly support not only active loads from superstructures but also the passive loads caused by soil lateral movement. To investigate the influence of passive load and the response along pile shafts of existing actively loaded piles, a load transfer model for analyzing the soil-pile interaction was developed based on plastic deformation theory and the triparameter soil model. An analytical solution for the deformation and internal force of such piles was proposed using the transfer matrix method, in which the transfer matrix coefficients for piles in free, plastic, and elastic zones were analytically obtained by considering the second-order axial force effect caused by lateral loading and soil yielding based on the triparameter soil model. The proposed methodology was validated by comparing its predictions with field measurements and previously published results. A good match between model predictions, field measurements, and previously published results implies that the proposed method can be used to evaluate the response of passive piles adjacent to a surcharge load. Parametric studies were also carried out to investigate the influence of surcharge pressure, soil resistance, and boundary conditions on the behavior of passively loaded piles adjacent to a surcharge load.
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Liu, Jinglei, Xiuxin Li, Jinyuan Cao, Zhengchun Duan, Qingzhi Ye, and Guishuai Feng. "Geometric Parameter Effects on Bandgap Characteristics of Periodic Pile Barriers in Passive Vibration Isolation." Symmetry 16, no. 9 (2024): 1130. http://dx.doi.org/10.3390/sym16091130.
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To investigate the impact of the geometric parameters of periodic pile barriers on bandgap characteristics in passive vibration isolation, a two-dimensional, three-component unit cell was developed using the finite element method (FEM). This study analyzed the bandgap properties of periodic pile barriers and validated the effectiveness of the FEM through model testing. The FEM was then methodically applied to evaluate the effects of pipe pile thickness, periodic constant, arrangement pattern, and cross-sectional shape on the bandgap characteristics, culminating in the proposition of a novel H-shaped cross-section for the piles. The results demonstrated that the FEM-calculated bandgap frequency range, featuring steel piles arranged in a square pattern, closely aligned with the attenuation zone in the model tests. The lower band frequency (LBF) was primarily influenced by the pipe pile’s inner radius, while the upper band frequency (UBF) was predominantly affected by its outer radius. As the periodic constant increased, the LBF, UBF, and the width of band gap (WBG) all decreased. Conversely, changing the arrangement pattern from square to hexagonal led to increases in UBF and WBG, while the LBF diminished. Notably, the WBG of the H-section steel piles, possessing the same cross-sectional area, was 1.31 times greater than that of the steel pipe piles, indicating an enhanced vibration isolation performance. Additionally, the impact of transverse and vertical characteristic dimensions of the H-shaped pile on the band gap distribution was assessed, revealing that the transverse characteristic dimensions exerted a more significant influence than the vertical dimensions.
6
Wang, Qingshan, Zhaoran Xiao, Xianqiang Zhao, and Dakuo Feng. "The Effects and Vertical Bearing Capacity of Two Jacked Model Piles in Sand." Sustainability 14, no. 21 (2022): 14493. http://dx.doi.org/10.3390/su142114493.
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The effects and vertical bearing capacity of two jacked piles in sand are still not well understood, and the mechanism of the adjacent pile’s uplift caused by the jacking pile in a double pile system is especially unclear, but these facets are important to the stability of the jacked pile. In this paper, a series of tests is performed on jacked model piles in sand, where in the influences of the pile length and the driving pile’s speed on the effects and vertical bearing capacity of two jacked piles were studied. The results revealed that the effects and vertical bearing capacity of the two jacked piles were mainly in relation to pile length and influenced by the driving speed. The horizontal displacement of the top of the first jacking pile during the installation of the post-jacking pile was caused by the difference in the stress state of the first jacking pile between the side of the pile’s face and its back side, in which the uplift displacement of the first jacking pile was also involved. The radial stress of the pile increased nonlinearly with the depth under different pile lengths and gradually converged to the passive earth pressure. The ultimate capacity of the double pile is approximately twice that of a single pile, and the ratio of the ultimate capacity of a single pile to the final jacking pressure was approximately 1.04.
7
Guo, Wei Dong. "Response of rigid piles during passive dragging." International Journal for Numerical and Analytical Methods in Geomechanics 40, no. 14 (2016): 1936–67. http://dx.doi.org/10.1002/nag.2490.
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Li, Tingting, Min Yang, and Xiaocen Chen. "A Simplified Analytical Method for the Deformation of Pile Foundations Induced by Adjacent Excavation in Soft Clay." Buildings 13, no. 8 (2023): 1919. http://dx.doi.org/10.3390/buildings13081919.
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The development of foundation excavations in congested urban areas inevitably induces stress release and soil movements, resulting in additional lateral deflections in adjacent pile foundations, commonly referred to as passive loading piles. Prior research on pile deflection resulting from nearby excavations primarily focused on single-pile behavior and paid little attention to the characteristics of pile groups. This paper presents a two-step approach to predicting the behavior of pile deformation resulting from nearby excavation. Firstly, Mindlin solution in combination with the double Gauss-Legendre formula is employed to calculate the additional lateral stress acting on the centerline of the passive pile resulting from nearby excavations. Secondly, the equation governing the deflection of the passive pile is determined using the Pasternak foundation model and solved using the finite difference method. On the basis of the Mindlin equation, shielding influence among piles is developed and applied to the analysis of a laterally loaded passive pile group. Last but not least, the accuracy of the presented approach is validated by comparing the results from two published centrifuge model tests with single piles and pile groups, and good agreements are obtained. Generally, the recommended two-step approach presents effective insight into the interaction between the excavation, soil, and pile, taking into account the influence of the shielding effect between piles. It can be applied as an alternative method for the conservation evaluation of the deformation tendency of pile foundation deformation in the pre-design of nearby excavations.
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Xie, Yu, Shao-he Zhang, and De-quan Zhou. "Experimental Study of Mechanical Behavior of Passive Loaded Piles Adjacent to Piled Foundation." KSCE Journal of Civil Engineering 22, no. 10 (2018): 3818–26. http://dx.doi.org/10.1007/s12205-018-0565-x.
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Karim, M. R., S. C. R. Lo, and C. T. Gnanendran. "Behaviour of piles subjected to passive loading due to embankment construction." Canadian Geotechnical Journal 51, no. 3 (2014): 303–10. http://dx.doi.org/10.1139/cgj-2012-0468.
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Behaviour of two embedded piles subjected to passive loading due to construction of an embankment was modelled in this paper. The piles were installed at the berm section of an embankment in a later stage of its construction. The investigation was carried out using a combination of two- and three-dimensional analyses. The analysis results were compared with the field-measured values and they agreed well.
11
Yuan, Bingxiang, Rui Chen, Jun Teng, Tao Peng, and Zhongwen Feng. "Effect of Passive Pile on 3D Ground Deformation and on Active Pile Response." Scientific World Journal 2014 (2014): 1–6. http://dx.doi.org/10.1155/2014/904186.
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Using a series of model tests, this study investigated the effect of a passive pile on 3D ground deformation around a laterally loaded pile and on that laterally loaded pile’s response in sand. The active pile head was subjected to lateral loads, and the passive pile was arranged in front of the active pile. In the model tests, the distance between the two pile centers was set to zero (i.e., a single pile test), 2.5, 4, and 6 times the pile width (B). The 3D ground surface deformations around the active and passive piles were obtained using a newly developed Stereo-PIV technique. The experimental results showed that the ground surface movements were restrained by the passive pile when the pile spacing was less than 6B. The response of the active pile was affected by the passive pile when the pile spacing was less than 4B. This study combined the response of the active pile and surrounding 3D ground deformation to investigate the effect of the passive pile, which is useful to further understand the pile-soil-pile interactions and to enhance pile foundation design in engineering practice.
12
Zhong, Mingchen, and Kun Meng. "Dynamic Interaction Factor of Pipe Group Piles Considering the Scattering Effect of Passive Piles." Journal of Marine Science and Engineering 11, no. 9 (2023): 1698. http://dx.doi.org/10.3390/jmse11091698.
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Based on the plane–strain assumption, a calculation model of pile–soil–pile vertical coupling vibration response considering the scattering effect of passive piles is established in this paper. Using this model, the vertical displacement expressions of pile core soil and pile surrounding soil, soil displacement attenuation function, and longitudinal complex impedance are obtained. Then, based on the strict pile–soil coupling effect, the displacement of the active pile under vertical load and scattering effect, as well as the displacement of the passive pile under incident waves, are solved separately. A new type of dynamic interaction factor for pipe group piles is derived by introducing scattering effect factors. A numerical example shows that the degenerate solution in this paper is in good agreement with the existing solution, which verifies the rationality of the solution. Considering the scattering effect is helpful in improving the accuracy of vibration response analysis of pile groups. The variation in parameters such as slenderness ratio, pile spacing, and outer diameter has significant effects on the interaction factor, and compared with the solid pile, the influence of parameter change on the pipe pile is smaller.
13
Feng, Qian, Han Xiao, Qingzhao Kong, Yabin Liang, and Gangbing Song. "Damage detection of concrete piles subject to typical damages using piezoceramic based passive sensing approach." Journal of Vibroengineering 18, no. 2 (2016): 801–12. http://dx.doi.org/10.21595/jve.2016.16631.
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Pile foundations are typically comprised in concealed construction work. In recent years, some major categories of concrete piles subject to typical damages have caused a lot of engineering disasters and accidents. These accidents have been caused by collapse of civil structures resulting in great casualties and economic loss. Therefore, damage detection and real-time health monitoring on foundation piles is an urgent research requirement. In this research, a piezoceramic based passive sensing approach is proposed to detect typical damages types of concrete piles, including partial mud intrusion, secondary concrete pouring interface, circumferential crack, and full mud intrusion. In this passive sensing approach, induced stress waves are generated by the impact hammer on the top surface of a pile and one smart aggregate embedded on the bottom of each pile is used as a sensor to receive the propagating wave signals. These sensors are embedded before pouring concrete. Structural defects affect the natural frequency of the pile. The power spectrum of piles with different types of damage were compared by plotting the sensor signals in frequency domain. The natural frequency decreases with the increase in defect severity. The experimental results demonstrate that the proposed approach can detect all four typical damage types in concrete piles.
14
Ahmed, Saad. Al Lami* Kais T. Shlash Mohammed A. Al-Neami. "EVALUATING THE EFFECT OF LATERAL SOIL MOVEMENT RATE ON THE BEHAVIOR OF PILES IN SAND USING PLAXIS." Global Journal of Engineering Science and Research Management 4, no. 5 (2017): 1–10. https://doi.org/10.5281/zenodo.573752.
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Pile foundations are not only used to support heavy structures and can act in the dual role of carrying the applied load to deeper and strong layers, but also to resist lateral loads generated from many sources as well as earthquake, earth pressure, waves, wind and soil movement due to creeping slop or excavation works. Piles response to external effects is divided into a passive pile and active pile. When the piles are subjected to lateral soil movements, these piles are known as passive piles. On the other hand, active piles referred to a pile subjected to external vertical and/or horizontal force. Soil movement is encountered in practice when piles are placed in an unstable slope, landslides, adjacent to deep excavation, tunnel operation, marginally stable riverbank with high fluctuating water level and also in piles supporting bridge abutment adjacent to approach embankments. PLAXIS 3D 2013 geotechnical finite element package which present 3- dimensional analysis for soil was utilized to build a numerical model of single pile and pile groups in lateral soil movement with different soil movement rates. The model confirmed using previous researches. The model verification shows favorable agreement with the measured horizontal pile deflections and bending moments by choosing appropriate parameters. Results from three-dimensional finite element show that high soil movement rates gave high horizontal displacement and bending moment then the lower rates. Also, the increasing of soil movement rate has more impact on the behavior of the single pile compared with the effect on pile groups under the same rate.
15
Guo, Wei Dong. "Nonlinear response of laterally loaded rigid piles in sliding soil." Canadian Geotechnical Journal 52, no. 7 (2015): 903–25. http://dx.doi.org/10.1139/cgj-2014-0168.
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This paper proposes a new, integrated two-layer model to capture nonlinear response of rotationally restrained laterally loaded rigid piles subjected to soil movement (sliding soil, or lateral spreading). First, typical pile response from model tests (using an inverse triangular loading profile) is presented, which includes profiles of ultimate on-pile force per unit length at typical sliding depths, and the evolution of pile deflection, rotation, and bending moment with soil movement. Second, a new model and closed-form expressions are developed for rotationally restrained passive piles in two-layer soil, subjected to various movement profiles. Third, the solutions are used to examine the impact of the rotational restraint on nonlinear response of bending moment, shear force, on-pile force per unit length, and pile deflection. Finally, they are compared with measured response of model piles in sliding soil, or subjected to lateral spreading, and that of an in situ test pile in moving soil. The study indicates the following: (i) nonlinear response of rigid passive piles is owing to elastic pile–soil interaction with a progressive increase in sliding depth, whether in sliding soil or subjected to lateral spreading; (ii) theoretical solutions for a uniform movement can be used to model other soil movement profiles upon using a modification factor in the movement and its depth; and (iii) a triangular and a uniform pressure profile on piles are theoretically deduced along lightly head-restrained, floating-base piles, and restrained-base piles, respectively, once subjected to lateral spreading. Nonlinear response of an in situ test pile in sliding soil and a model pile subjected to lateral spreading is elaborated to highlight the use and the advantages of the proposed solutions, along with the ranges of four design parameters deduced from 10 test piles.
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Rifat Kahyaoglu, M., Gökhan Imancli, A. Ugur Ozturk, and Arif S. Kayalar. "Computational 3D finite element analyses of model passive piles." Computational Materials Science 46, no. 1 (2009): 193–202. http://dx.doi.org/10.1016/j.commatsci.2009.02.022.
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Guo, W. D. "Elastic models for nonlinear response of rigid passive piles." International Journal for Numerical and Analytical Methods in Geomechanics 38, no. 18 (2014): 1969–89. http://dx.doi.org/10.1002/nag.2292.
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Pan, J. L., A. TC Goh, K. S. Wong, and C. I. Teh. "Model tests on single piles in soft clay." Canadian Geotechnical Journal 37, no. 4 (2000): 890–97. http://dx.doi.org/10.1139/t00-001.
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Laboratory model tests in soft clay were conducted to investigate the behaviour of single piles subjected to lateral soil movements ('passive' pile), and to determine the ultimate soil pressure acting along the pile shaft. A specially designed apparatus for the tests was manufactured and calibrated. Reasonably consistent soil samples were prepared for the tests by a consolidometer. The limiting soil pressures acting along the model pile shaft were measured by pressure transducers. The ultimate soil pressure was then determined based on the maximum value of the limiting soil pressures acting along the pile shaft. The ultimate soil pressure obtained from the single passive pile tests was 10.6su (where su is the undrained shear strength of the clay) and agreed well with those from the literature.Key words: pile, foundation, lateral soil movement, clay, model test.
19
Wei, Limin, Kaixin Zhang, Qun He, and Chaofan Zhang. "Mechanical Response Analysis for an Active–Passive Pile Adjacent to Surcharge Load." Applied Sciences 13, no. 7 (2023): 4196. http://dx.doi.org/10.3390/app13074196.
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Due to the complexity of pile–soil interaction, there is little research on active–passive piles that bear the pile-top load transmitted from the superstructure and the pile shaft load caused by the lateral soil movement around the pile simultaneously. The purpose of this study is to analyze the displacement and internal force of active–passive piles. Most of the pile design codes in China use the elastic resistance method to describe the relationship between the lateral soil resistance and the horizontal displacement of the pile, but this is not accurate enough to analyze the internal force and deformation of the pile when the pile displacement is large. For this case, the passive load on the pile shaft caused by the adjacent surcharge load can be described in stages, and the p–y curve method can be used to express the relationship between the lateral soil resistance and the horizontal displacement of the pile. Additionally, taking both the active load (vertical force, horizontal force, and bending moment on the pile top) and the passive load into account, the deflection differential equation of the pile shaft is herein established, and a corresponding finite difference method program is implemented to obtain the calculations pursuant to the equation. The correctness of the analysis method and program was verified by two test cases. The results show that our calculation method can effectively judge the flow state of the soil around piles and accurately reflect the nonlinear characteristics of pile-soil interaction. Moreover, the influence depth of the pile displacement under the passive pile condition caused by the adjacent load is significantly greater than that under active pile condition, and the maximum pile-bending moment appears near the interface of soft and hard soil layer.
20
Mekdash, Hani, Lina Jaber, Yehya Temsah, and Marwan Sadek. "Reinforcement of Concrete Shoring Systems by Prestressing." Advances in Civil Engineering 2022 (September 23, 2022): 1–10. http://dx.doi.org/10.1155/2022/2383781.
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Reinforced concrete piles are useful structural elements to support deep excavations. A pile wall is usually supported by one or several rows of anchors, depending on the depth of the excavation and the nature of the soil retained. The purpose of this work is to investigate the efficacy of posttensioned piles in retaining a 10.0 m deep excavation without using tieback anchors. In addition to the conventional passive steel reinforcement, the piles in this system include steel strands placed eccentrically in their sections, and they are referred to as posttensioned piles. The performance of posttensioned piles is investigated using the finite element modeling software PLAXIS 2D. The results are experimentally validated on a large-scale construction site. The horizontal displacement of posttensioned piles in a 10 m deep excavation was found to be within allowable limits with a 7.36% difference in the horizontal displacement of pile top at the final excavation level in PLAXIS 2D. In terms of cost, PTP is executed at 35% cost less than the conventional reinforced method.
21
Yang, Minghui, Bo Deng, and Yuhui Wang. "A Simplified Calculation Method for the Near-Slope Laterally Loaded Pile Based on a Passive Wedge Model." Advances in Civil Engineering 2019 (July 1, 2019): 1–10. http://dx.doi.org/10.1155/2019/8363252.
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When a pile is placed near the slope, the lateral loading capacity of the pile decreases significantly due to the weakening effect of soil resistance near the slope. As such, a modified soil passive wedge model for near-slope laterally loaded piles is presented to consider the weakening effect in this paper. According to development depth of different wedges, the shapes of soil passive wedge can be classified into three sorts, so as to fully analyze the influence of the slope shape and the distance from the pile center to the slope crest. On this basis, a concept of equivalent depth is proposed considering the differences of laterally loaded piles near the slope and in the horizontal ground. Besides, the unit ultimate soil resistance, which can be obtained along the different depths of pile, is introduced into the p-y curve of the soil, for achieving solution methods of internal force and displacement of laterally loaded piles under the slope weakening effect. The results of laboratory model and field tests on laterally loaded piles are compared with the proposed method, demonstrating its validity and accuracy. Furthermore, the influence of the near-slope distance on the loading capacity of the pile is fully analyzed in detail, indicating the critical near-slope distance is increasing with the increase of the undrained strength, while independent of the slope angle.
22
Carrubba, Paolo, and Claudia Pergola. "Practical Considerations in the Design of Passive Free Piles in Sliding Soil." Applied Sciences 14, no. 8 (2024): 3334. http://dx.doi.org/10.3390/app14083334.
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The stabilisation of shallow translational landslides can be carried out by using large diameter concrete piles, with the aim of increasing the available strength along the slip surface. In the following article, 3D numerical models of a free-head flexible pile embedded into a translational type of landslide are studied. The landslide model has a given inclination angle, β, and a thickness, D, while the reinforced concrete pile has a fixed diameter, d, and a length, D + L, in the perspective of studying the failure modes B1, BY and B2 of free-head flexible piles. In this category of piles, collapse is reached with the formation of plastic hinges. Both the soil and the concrete are modelled with simple constitutive models, such as Mohr–Coulomb for soil and the elastic-perfectly plastic for the concrete pile, in order to carry out the design approaches provided by Eurocode, as well as to highlight some practical aspects of soil–structure interaction during the landslide displacements. The results highlight how the achievement of the shear strength in a flexible free-head concrete pile generally precedes the achievement of the ultimate bending moment associated with the development of plastic hinges. Furthermore, the axial load supported by the pile may itself contribute to the overall strength available along the slip surface.
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Bellezza, I., and L. Caferri. "Ultimate lateral resistance of passive piles in non-cohesive soils." Géotechnique Letters 8, no. 1 (2018): 5–12. http://dx.doi.org/10.1680/jgele.17.00113.
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Li, Bing Lei, Yong Tao Gao, and Shun Chuan Wu. "Passive Pile Calculation Model and its Reasonable Distance of Piles." Advanced Materials Research 243-249 (May 2011): 2100–2107. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.2100.
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The traditional method of calculating soil arch effect was described Firstly, and the inadequacy of traditional methods was analyzed. On the basis of their predecessors, the rectangular cross section of a rational spacing between passive pile was mainly discussed. Based on the mechanical properties of soil between anti-slide piles analysis, a pile of soil conditions of static equilibrium, cross-section strength of the section of the conditions and strength condition of the arch to common control methods to determine the critical pile space were put forward.Relatively reasonable a spacing formula for calculating pile spacing has been obtained. Comparing with rational pile space formula obtained and the traditional formula for the actual project data, the results indicate that, for the cross-section 2.5mx2.5m the pile, formula by rational pile space the calculated results and the calculation method has been compared and analyzed the results, when the landslide thrust 47kN/m2.According to rational pile space formula the results calculated by the situation more in line with the actual project, it is of significance to practical engineering design of anti-slide pile, and there is a greater using and reference value for the similar project via the methods used and the conclusion.
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Kok, S. T., B. B. K. Huat, Jamaloddin Noorzaei, Mohd Saleh Jaafar, and S. S. Gue. "A Case Study of Passive Piles Failure in Open Excavation." DFI Journal - The Journal of the Deep Foundations Institute 3, no. 2 (2009): 49–56. http://dx.doi.org/10.1179/dfi.2009.011.
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Wang, Shu Yun, and Xiong Gang Xie. "Safety Analysis for Rock Slope Reinforced by Piles with Computer Aided Design Method." Advanced Materials Research 291-294 (July 2011): 355–58. http://dx.doi.org/10.4028/www.scientific.net/amr.291-294.355.
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The stabilization of slopes by placing passive piles is one of the innovative slope reinforcement techniques in recent years. There are numerous empirical and numerical methods for designing stabilizing piles. They can generally be classified into two different types: (1) pressure/displacement-based methods; (2) finite element/finite difference methods. However, seldom studies have been done on the stratified rock slope reinforced by piles, so in the present paper, the numerical simulation software FLAC3D is adopted to model the stratified rock slope, then the reinforced effect like deformation and stress of slope are studied, showing that if the pile is driven at the mid-bottom place of slope surface, the effect of controlling deformation of rock mass is the best. With increase of the length of pile, the maximum displacement of slope is decreased gradually.
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Poulsen, Søren Erbs, Maria Alberdi-Pagola, Davide Cerra, and Anna Magrini. "An Experimental and Numerical Case Study of Passive Building Cooling with Foundation Pile Heat Exchangers in Denmark." Energies 12, no. 14 (2019): 2697. http://dx.doi.org/10.3390/en12142697.
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Technologies for energy-efficient cooling of buildings are in high demand due to the heavy CO2 footprint of traditional air conditioning methods. The ground source heat pump system (GSHP) installed at the Rosborg Gymnasium in Vejle (Denmark) uses foundation pile heat exchangers (energy piles). Although designed for passive cooling, the GSHP is used exclusively for heating. In a five-week test during the summer of 2018, excess building heat was rejected passively to the energy piles and the ground. Measured energy efficiency ratios are 24–36 and the thermal comfort in conditioned rooms is improved significantly relative to unconditioned reference rooms. A simple model relating the available cooling power to conditioned room and ground temperatures is developed and calibrated to measured test data. Building energy simulation based estimates of the total cooling demand of the building are then compared to corresponding model calculations of the available cooling capacity. The comparison shows that passive cooling is able to meet the cooling demand of Rosborg Gymnasium except for 7–17 h per year, given that room temperatures are constrained to < 26 °C. The case study clearly demonstrates the potential for increasing thermal comfort during summer with highly efficient passive cooling by rejecting excess building heat to the ground.
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Zuo, Liangdong, Quanbao Wang, and Jia Liu. "Experimental Study on the Symmetry of the Soil-Arching Effect of a Pile Foundation in a Reinforced High-Fill Area." Symmetry 17, no. 2 (2025): 188. https://doi.org/10.3390/sym17020188.
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In addition to the vertical external load and soil settlement load, the pile foundation in reinforced high-fill areas is also affected by the horizontal load caused by the rear stacking load, and pile stress is affected by the soil-arching effect in reinforced areas that have typical passive pile characteristics. In order to study the symmetry of the soil-arching effect of pile foundations in a reinforced-fill area, indoor model tests were designed and the relevant data for the pile foundation and reinforced soil under surcharge were obtained. Through the analysis, the following conclusions were drawn: the peak bending moment of the pile body is basically consistent with the position of the potential sliding surface of reinforced soil; the maximum shear force of the pile body appears about 150 mm below the embedding point; with an increase in depth, the soil-arching effect becomes obvious. There are two different forms of friction, soil-arching and direct soil-arching between piles and behind piles, and the soil between single-row piles has a symmetrical distribution. In addition to the vertical external load and soil settlement load, the pile foundation in reinforced high-fill areas will also be affected by the horizontal load caused by the rear stacking load, and pile stress will be affected by the soil-arching effect in reinforced areas, which has typical passive pile characteristics. In order to study the symmetry of the soil-arching effect of pile foundations in a reinforced-fill area, indoor model tests were designed, and the relevant data for pile foundation and reinforced soil under surcharge were obtained. Through analysis, the following conclusions were drawn: (1) the peak bending moment of the pile body is basically consistent with the position of the potential sliding surface of reinforced soil; the maximum shear force of the pile body appears about 150 mm below the embedding point; with an increase in depth, the soil-arching effect becomes obvious. There are two different forms of friction, soil-arching and direct soil-arching between piles and behind piles, and the soil between single-row piles has a symmetrical distribution.
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Xia, Xiong, Yi Bo Wang, Han Dong Xu, Sai Ying Xi, and Yi Huang. "Study on Active Earth Pressure of Sheet Pile Model Test on Foundation Pit Engineering." Advanced Materials Research 1049-1050 (October 2014): 209–12. http://dx.doi.org/10.4028/www.scientific.net/amr.1049-1050.209.
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In recent years, building density in the city is increasing as the promoting of urban modernization. Deep foundation pit excavation and bracing is a topic in geotechnical engineering, including strength and stabilization of soil mechanics, and transmutation and sedimentation of deep foundation, and common effect between soil and shoring structure. The paper based on the design and fabrication of indoor model test device. This paper respectively explored the destroy mechanism of cantilever and anchored sheet pile support structure on the soil pressure under the different loads, and comprehensively carried through cantilever and anchored sheet pile support test under four-grades excavation depth and four-grades load combination, and specially researched the transformation of soil pressure. At the same time, the piles spacing changed among 3cm, 4cm and 5cm. Theoretical results showed that the active earth pressure increased with the increase of load and excavation depth. Model test results showed that the earth pressure behind the piles increased with the increase of excavation depth and the load. The biggest earth pressure was 19.38kPa when loading 40kPa. The changing curves of soil pressure were similar when piles spacing was 3cm and 4cm. Earth pressure after the piles was negative when piles spacing exceeded 4cm, which illustrated that active earth pressure had changed into passive soil pressure.
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Xu, K. J., and H. G. Poulos. "3-D elastic analysis of vertical piles subjected to “passive” loadings." Computers and Geotechnics 28, no. 5 (2001): 349–75. http://dx.doi.org/10.1016/s0266-352x(00)00024-0.
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Zhang, Hao, Minglei Shi, and Yuancheng Guo. "Semianalytical Solutions for Abutment Piles Under Combined Active and Passive Loading." International Journal of Geomechanics 20, no. 10 (2020): 04020171. http://dx.doi.org/10.1061/(asce)gm.1943-5622.0001804.
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Sun, Yue, Zhi Yun Wang, Yue Nan Chen, and Yun Shen Jiang. "Numerical Analysis of Passive Pile due to Excavation." Advanced Materials Research 594-597 (November 2012): 198–201. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.198.
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An elasto-plastic total stress finite-element computational model is established in two dimensional space to study pile response due to excavation-induced soil movement on the basis of the general-purpose finite element software ABAQUS. And the soil is assumed to be a uniform normally consolidated clay layer. Influences of various parameters including undrained shear strength of soil, excavation depth, strut stiffness and distance from excavation on pile response are investigated. The results indicate that the excavation-induced soil movement is critical for adjacent piles and increasing the undrained shear strength of soil and distance from excavation face would be helpful to control passive pile responses.
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Hong, Y., and Charles W. W. Ng. "Base stability of multi-propped excavations in soft clay subjected to hydraulic uplift." Canadian Geotechnical Journal 50, no. 2 (2013): 153–64. http://dx.doi.org/10.1139/cgj-2012-0170.
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Excavations in soft clay underlain with an aquifer may be destabilized by hydraulic uplift. Previous studies on this subject are based mainly on field observations. Dewatering from the aquifer is a common method to improve base stability where ground settlement is not a major concern. Alternatively, piles readily installed as part of the top-down construction method for multi-propped excavation may be considered to provide base stability and minimize ground settlement outside the excavation. This paper presents results from two centrifuge tests that were conducted to simulate multi-propped excavations in-flight (with and without piles) in soft clay destabilized by hydraulic pressure from an underlying sand aquifer. Moreover, coupled three-dimensional finite element analyses were carried out to back-analyse the centrifuge tests. Numerical parametric studies were also conducted to study the influence of pile length on the effectiveness of base stabilization. It is revealed that both for excavations with and without piles, the artesian pressure required to initiate uplift inside the excavation is about 1.2 times the overburden pressure of the clay. By using “anti-uplift” piles inside the excavation, the ultimate hydraulic uplift resistance increases by 16%, while the uplift movement can be reduced by 80%. The presence of piles also increases the passive resistance in front of the wall by 70%, but reduces the mobilized undrained shear strength, cu, of clay by 53%.
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Zhou, Yijun, and Yulong Chen. "Active and Passive Earth Pressure Calculation Method for Double-Row Piles considering the Nonlinear Pile Deformation." Geofluids 2022 (April 26, 2022): 1–17. http://dx.doi.org/10.1155/2022/4061624.
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The double-row pile supporting structure has been widely used in foundation pit excavations. When analyzing the effect of earth pressure on the pile structure, previous research only considered the double-row piles as the rigid body and the pile-soil interaction has not been examined. In this study, a theoretical model was developed based on Duncan-Chang’s hyperbolic theory to calculate earth pressures in the active and passive zones of the double-row pile supporting structure. The model considered the nonlinear effect of the pile deformation on the active and passive earth pressures. The macroscopic pile-soil interaction was converted into a microscopic stress-strain relationship at a certain point in the soil body, reflecting the nonlinear effect of pile deformation on earth pressure. Numerical simulation and large-scale field tests have been conducted to verify the proposed model. The results show that the average values of the parameters obtained by numerical simulation are a ¯ = 0.38 , b ¯ = − 0.253 for the active zone and a ¯ = 0.00612 , b ¯ = − 0.729 for the passive zone. Based on the values of a ¯ and b ¯ , the predicted active and passive earth pressures stemming from the developed model agreed well with those obtained from field tests. The developed model in this study can be used to predict the distribution of active and passive earth pressures for double-row pile supporting structures.
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Zhou, Yijun, and Yulong Chen. "Active and Passive Earth Pressure Calculation Method for Double-Row Piles considering the Nonlinear Pile Deformation." Geofluids 2022 (April 26, 2022): 1–17. http://dx.doi.org/10.1155/2022/4061624.
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The double-row pile supporting structure has been widely used in foundation pit excavations. When analyzing the effect of earth pressure on the pile structure, previous research only considered the double-row piles as the rigid body and the pile-soil interaction has not been examined. In this study, a theoretical model was developed based on Duncan-Chang’s hyperbolic theory to calculate earth pressures in the active and passive zones of the double-row pile supporting structure. The model considered the nonlinear effect of the pile deformation on the active and passive earth pressures. The macroscopic pile-soil interaction was converted into a microscopic stress-strain relationship at a certain point in the soil body, reflecting the nonlinear effect of pile deformation on earth pressure. Numerical simulation and large-scale field tests have been conducted to verify the proposed model. The results show that the average values of the parameters obtained by numerical simulation are a ¯ = 0.38 , b ¯ = − 0.253 for the active zone and a ¯ = 0.00612 , b ¯ = − 0.729 for the passive zone. Based on the values of a ¯ and b ¯ , the predicted active and passive earth pressures stemming from the developed model agreed well with those obtained from field tests. The developed model in this study can be used to predict the distribution of active and passive earth pressures for double-row pile supporting structures.
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Fan, Xiaozhen, Changjie Xu, and Luju Liang. "Experimental and Theoretical Study for a Displacement-Controlled Design Method of Embedded Cantilever Retaining Walls (Piles)." Sustainability 15, no. 12 (2023): 9831. http://dx.doi.org/10.3390/su15129831.
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Displacement control is critical to the design of retaining walls, especially in urban areas, to avoid any potential damage to adjacent structures during excavations. In this study, model tests are first conducted to investigate the stress and deformation mechanisms of an embedded cantilevered retaining (ECR) wall during excavations. The development of the wall top displacement and the active and passive earth pressures acting on the ECR walls during excavations are studied. Upon the experimental observations, a displacement-dependent earth pressure coefficient is proposed to derive an analytical solution to predict both the active and passive earth pressure acting on the ECR wall (pile), where the displacement value and displacement mode of the ECR wall (pile) are taken into account. Comparisons between the model predictions and test results are carried out. A good agreement is observed, which shows the validity of the proposed solution. Based on the proposed solution, a displacement-controlled method for the design of ECR walls (piles) that takes into account the location of the rotation point is proposed. Parametric studies are conducted to demonstrate the impact of deformation control and excavation depth on the design parameters of ECR walls (piles).
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Kim, Dae Sang, and Ung Jin Kim. "Evaluation of Passive Soil Stiffness for the Development of Integral Abutments for Railways." Journal of the Korean Society of Hazard Mitigation 20, no. 4 (2020): 13–19. http://dx.doi.org/10.9798/kosham.2020.20.4.13.
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An integral bridge, which is constructed without expansion joints and bearings, is an economical technology that permits slender abutment and footing design to decrease the associated maintenance and construction costs. In this study, a geosynthetic reinforced integral abutment (IA) for railways and a conventional reinforced concrete abutment (CA) are modeled, considering the two types of foundations, using the finite element method. The passive soil stiffness of the foundations was evaluated through the application of a uniform horizontal load in four separate models. The passive soil stiffness of the IA model is approximately 70% of that of the CA model. Additionally, we confirmed that the passive soil stiffness was affected by changes in the thickness of the abutment, size of the footing, number of installation piles, and elastic modulus of the ground.
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Sliwa, Tomasz, Aneta Sapińska-Śliwa, Tomasz Wysogląd, Tomasz Kowalski, and Izabela Konopka. "Strength Tests of Hardened Cement Slurries for Energy Piles, with the Addition of Graphite and Graphene, in Terms of Increasing the Heat Transfer Efficiency." Energies 14, no. 4 (2021): 1190. http://dx.doi.org/10.3390/en14041190.
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The development of civilization, and subsequent increase in the number of new buildings, poses engineering problems which are progressively more difficult to solve, especially in the field of geotechnics and geoengineering. When designing new facilities, particular attention should be paid to environmental aspects, and thus any new facility should be a passive building, fully self-sufficient in energy. The use of load-bearing energy piles could be a solution. This article presents research on the cement slurry formulas with the addition of graphite and graphene, that can be used as a material for load-bearing piles. The proposed solution is to introduce U-tubes into the pile to exchange heat with the rock mass (the so-called energy piles). A comparison of four slurry formulas is presented: the first one consisting mainly of cement (CEM I), graphite, and water, and the remaining three with different percentages of graphene relative to the weight of dry cement. The results could contribute to the industrial application of those formulas in the future.
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Zhang, Hao, and Kai Sun. "Influence of Surcharge Load on the Adjacent Pile Foundation in Coastal Floodplain." Insight - Civil Engineering 4, no. 1 (2021): 312. http://dx.doi.org/10.18282/ice.v4i1.312.
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In this paper, in order to investigate the behavior of existing piles caused by the horizontal and compression deformation of soft substratum due to backfill surcharge on coastal floodplain, three-dimensional finite element models of piles adjacent to surcharge load were established. The deformation and migration law of soft soil was analyzed. The behavior of single pile and double row pile adjacent to surcharge load were studied, in which the influence of surcharge load location, surcharge pressure, pile stiffness, and pile top constraint conditions were considered. The results show that as the position of surcharge load is closer and the surcharge pressure increases, the response (e.g. deformation and bending moment) is more obvious. With the increase of pile stiffness, the range of passive load is increased. The deformation behavior of pile body under different constraints of pile cap is significantly different. The effect of secondary bending moment caused by pile axial force is obvious and cannot be ignored. If there is a thick soft substratum, it is beneficial to improve the behavior of adjacent piles by using cement mixing pile reinforcement.
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Su, Tiantao, Yong Zhou, Zhengzhen Wang, and Shuaihua Ye. "Large Scale Model Test Study of Foundation Pit Supported by Pile Anchors." Applied Sciences 12, no. 19 (2022): 9792. http://dx.doi.org/10.3390/app12199792.
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Due to the special time–space and environmental effects of the foundation pit, there are many unstable factors in the construction process of the field test. The indoor model test can avoid many uncertainties in the construction process due to its operability, which can reduce the interference with the test results and improve the accuracy of the test. In order to further discuss the force-bearing characteristics and deformation laws of loess pits’ support structure in Northwest China, a large model test of foundation pit supported by a pile anchor with a geometric similarity ratio of 1:10 was designed and completed. The force and deformation characteristics of the support structure were systematically studied by simulating the conditions of additional load at the pit edge, soil layered excavated, and anchors tensioned. The test results show that: for the pile-anchor support structure, the anchors have significant limiting effects on the displacement of the piles. Especially, when the position of the first row of anchors is closer to the pile top, the displacement of the pile is smaller. The stress state of the piles was changed by the prestressed anchor. The passive stress state of piles is changed from one side of tension and the other side of compression to the active stress state of “S” shape, which makes the distribution of the bending moment of piles more reasonable. The measured earth pressure in the process of soil unloading has a nonlinear distribution, which is different from the classical Rankine earth pressure distribution; specifically, the passive earth pressure in front of the pile is more obvious. In addition, the prestress applied to the anchors has a more significant effect on the internal forces of the other anchors. Compared with sequential tensioning, the prestress loss caused by interval hole tensioning is significantly reduced. The greater the number of spaced holes, the smaller the prestress loss and the better the anchoring effect of the anchor. The results of the study can provide reference for similar model tests, and also for related engineering applications.
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Hu, Shunlei, Yan Zhuang, Yifan Wu, Xidong Zhang, and Xiaoqiang Dong. "Numerical Study of Bearing Capacity of the Pile-Supported Embankments for the Flexible Floating, Rigid Floating and End-Bearing Piles." Symmetry 14, no. 10 (2022): 1981. http://dx.doi.org/10.3390/sym14101981.
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Floating pile-supported embankment involves more complex load transfer mechanisms, and there are no clear uniform guidelines available for its design. The concepts of flexible floating, rigid floating and end-bearing pile-supported embankments were proposed in this paper. Based on three typical field cases, their pile-soil interactions and soil arching effect were examined using the three-dimensional finite element method. Due to symmetry, only a half-width embankment model was simulated here. It has been found that the flexible floating piles carry the load mainly relying on the skin friction, but end-bearing piles rely on the pile tip resistance. The rigid floating piles were somehow in between. The earth pressure coefficient (K) in the end-bearing pile-supported embankment reached a maximum of 3.28, greater than Rankine passive values of the earth pressure coefficient (KP), in which the soil arching was fully developed. The K in the embankment with rigid floating pile reached 2.21, where soil arching might be partially formed. At the bottom of the flexible floating pile-supported embankment, the K tended to equal the Rankine active values of the earth pressure coefficient (Ka), and thus soil arching was insignificant. It has also been found that using rigid floating piles might significantly improve the bearing capacity of the embankments and was cost-effective for deep soft soil areas.
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Li, Tingting, Min Yang, and Xiaocen Chen. "Lateral Deformation Response of an Adjacent Passive Pile under the Combined Action of Surcharge Loading and Foundation Excavation." Sustainability 15, no. 18 (2023): 13619. http://dx.doi.org/10.3390/su151813619.
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With the increasing development of civil engineering in large cities, more and more excavations and surcharge loadings are being constructed or planned adjacent to existing building piles in crowded urban areas. Previous study on pile deformation has primarily focused on surcharge loading or foundation excavation and given little concern to the combined action of surcharge loading and foundation excavation. The article develops a two-stage process to assess the lateral displacement of nearby pile foundations induced by the combined action of surcharge loading and excavation. Firstly, the local plastic deformation theory and Boussinesq solution are used to accurately predict the passive loading of adjacent pile foundations caused by surcharge loading; Mindlin formulas are adopted to predict the passive pile’s additional lateral stress applied by excavation. Secondly, Pasternak models are adopted and the finite difference method is used to establish the deflection differential formula of the single passive pile. Last but not least, a parametric study is conducted to investigate the influence of the loading dimensions, loading magnitudes, and three-dimensional excavation dimensions. The findings of the calculations reveal that the loading magnitudes have a more significant impact on the lateral displacement of the pile compared to the loading dimensions. Therefore, a concentrated surcharge loading should be avoided. Additionally, the excavation depth has a greater influence on the lateral displacement of the pile compared to the excavation area. In order to mitigate this situation, a step excavation should be implemented for each layer of soil, with the soil excavated away from the pile foundation first.
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Gu, Meixiang, Xiaocong Cai, Qiang Fu, Haibo Li, Xi Wang, and Binbing Mao. "Numerical Analysis of Passive Piles under Surcharge Load in Extensively Deep Soft Soil." Buildings 12, no. 11 (2022): 1988. http://dx.doi.org/10.3390/buildings12111988.
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The three-dimensional finite difference method was used in this study to analyze the deformation and stresses of a passive pile under surcharge load in extensively deep soft soil. A three-dimensional numerical model was proposed and verified by a field test. The horizontal displacements of the pile agreed well with the field results. This study investigated the pile-foundation soil interaction, the load transfer mechanism, the excess pore water pressure (EPWP), and the horizontal resistance of the foundation soil. The results show that the soil in the corner of the loading area developed a large uplift deformation, while the center of the loading area developed a large settlement. The lateral displacement of the pile decreased sharply with the increase of the depth and increased with the surcharge load. The lateral displacement of the soil was negligible when the depth exceeded 30 m. The EPWP increased in a nonlinear way with the increase of the surcharge load and accumulated with the placement of the new lift. The distribution of the lateral earth pressure in the shallow soil layer was complex, and the negative value was observed under a high surcharge load due to the suction effect. The proportion coefficient of the horizontal resistance coefficient showed much smaller value in the situation of large lateral deformation and high surcharge load. The design code overestimated the horizontal resistance of the shallow foundation soil, which should be given attention for the design and analysis of the laterally loaded structures in extensively soft soil.
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Wang, Edward. "Seismic Retrofit of Pile Group Foundation with Thickened Caps." Open Construction and Building Technology Journal 9, no. 1 (2015): 248–54. http://dx.doi.org/10.2174/1874836801509010248.
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The case studied in the paper proves that thickening the pile cap is an effective seismic retrofit alternative to strengthen a pile group foundation. Unlike the typical seismic retrofitting of foundation, the proposed method eliminates the need to drive long piles into existing bridge substructures, substantially reducing cost, construction time and traffic interruption. The method thickens the pile cap of the bridge foundation to engage with a larger quantity of soil when under the influence of seismic excitations. The additional friction provided by the surface of the concrete encasement helps to resist the overturning moment of the earthquake forces, while the passive pressure provided by the soil helps to resist lateral forces during earthquakes. The method is recommended for implementation in the freeway bridge retrofit project in Taiwan due to construction constraints. A successful retrofit requires existing piles in at least moderate condition, detailed construction sequences and installation of the encasement.
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Rodas-Gaitán, Heberto Antonio, José Manuel Palma-García, Emilio Olivares-Sáenz, Edgar Vladimir Gutiérrez-Castorena, and Rigoberto Vázquez-Alvarado. "Biodynamic preparations on static pile composting from prickly pear cactus and moringa crop wastes." Open Agriculture 4, no. 1 (2019): 247–57. http://dx.doi.org/10.1515/opag-2019-0023.
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AbstractBiodynamic agriculture, which considered biodynamic preparations (BP) and compost as essential to farms sustainability, surged as an alternative almost a century ago. Composting is a way to obtain either biofertilizers or soil amendments, whereas the static piles method reduces energy and cost because no turnings are needed. The present study aims to evaluate the BP effect on physical, chemical and biological properties of static piles compost from prickly pear cactus and moringa crop wastes (regional principal substrates) over 100 days of composting. The experiment was carried out in an organic farm (Nuevo León, Mexico) considering four treatments: T1, Prickly pear cactus+BP; T2, Moringa+BP; T3, Prickly pear cactus and T4, Moringa. Results showed significantly higher bacterial activity (p<0.05) in T1 (until 1.38x1010CFU), therefore it had the highest temperatures and mineralization. Treatments with prickly pear cactus attained the highest temperatures, compared with those with moringa (significantly in 71% of total sampling days, p<0.05). An aerobic environment was maintained by the passive aeration system (holed PVC pipes placed at the bottom layer). The final material was considered to be sanitized, according to Enterobacteriaceae,Escherichia coliandSalmonella/Shigellaanalysis for quality control. Results indicate the BP efficiency on regional substrates decomposition, by using the static piles method.
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Gao, G. Y., Z. Y. Li, Ch Qiu, and Z. Q. Yue. "Three-dimensional analysis of rows of piles as passive barriers for ground vibration isolation." Soil Dynamics and Earthquake Engineering 26, no. 11 (2006): 1015–27. http://dx.doi.org/10.1016/j.soildyn.2006.02.005.
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Yao, Yu, Xuefei Shi, and Dongdong Han. "Lateral Effects of Jet Grouting on Surrounding Soil and Circular Diaphragm Walls." Buildings 14, no. 11 (2024): 3587. http://dx.doi.org/10.3390/buildings14113587.
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The installation of high-pressure jet grout piles induces significant lateral soil displacement, which can adversely affect nearby structures, such as diaphragm walls. Based on field tests, this study systematically analyzes the lateral displacement of soil caused by two distinct grouting techniques: the intelligent sensing super jet pile (SJT) technique and the Rodin jet pile (RJP) technique. Experimental results show that the SJT technique induces less disturbance to surrounding soil, with a maximum lateral displacement of approximately 6 mm at the closest inclinometer and an influence range limited to about 4 m. A theoretical model, based on passive pile theory, was developed to predict the lateral deflection of diaphragm walls due to adjacent jet grouting. Using a finite difference algorithm, bending moments on the walls were calculated and compared to measured data, showing a consistent correlation between predictions and observations. These findings are crucial for the design and construction of jet grout piles near sensitive structures, ensuring the safety and reliability of soil improvement practices and underground engineering.
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Dixon, Roger. "Stabilisation of the Jackfield slope at Ironbridge Gorge, Shropshire." Structural Engineer 94, no. 10 (2016): 12–21. http://dx.doi.org/10.56330/nnxj3027.
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The Ironbridge Gorge in Shropshire, UK, is young in geological terms and is generally prone to slope instability. Jackfield is an area on the banks of the River Severn that has a record of known slippages; these are put into geological and historical context. A scheme was proposed to stabilise the slope, adopting a hybrid method of analysis and design. The evolution of this scheme is outlined with particular emphasis on the design of the piles that were a fundamental part of the solution. Piles were used to stabilise the landslide by mobilising available passive resistance in the underlying stable ground mass and transmitting that resistance into the overlying slide mass, adopting the Viggiani method. The difference between the approaches of the geotechnical and structural aspects of the design is discussed in some detail as the design team was careful to avoid compounding factors of safety; this is illustrated by a numerical example. The determination of pile strength is outlined and a worked example for ascertaining pile spacing is included along with installation details.
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Jie, Yu-xin, Hui-na Yuan, Hou-de Zhou, and Yu-zhen Yu. "Bending Moment Calculations for Piles Based on the Finite Element Method." Journal of Applied Mathematics 2013 (2013): 1–19. http://dx.doi.org/10.1155/2013/784583.
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Using the finite element analysis program ABAQUS, a series of calculations on a cantilever beam, pile, and sheet pile wall were made to investigate the bending moment computational methods. The analyses demonstrated that the shear locking is not significant for the passive pile embedded in soil. Therefore, higher-order elements are not always necessary in the computation. The number of grids across the pile section is important for bending moment calculated with stress and less significant for that calculated with displacement. Although computing bending moment with displacement requires fewer grid numbers across the pile section, it sometimes results in variation of the results. For displacement calculation, a pile row can be suitably represented by an equivalent sheet pile wall, whereas the resulting bending moments may be different. Calculated results of bending moment may differ greatly with different grid partitions and computational methods. Therefore, a comparison of results is necessary when performing the analysis.
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TAKANO, Daiki, Fumitaka ARAI, Yoshiyuki MORIKAWA, Yasunari MATSUO, and Yoshiaki HAMANO. "CENTRIFUGAL MODEL TEST ON THE PASSIVE RESISTANCE OF STEEL PIPE SHEET PILES WITH SOIL IMPROVEMENT." Journal of Japan Society of Civil Engineers, Ser. B3 (Ocean Engineering) 76, no. 2 (2020): I_480—I_485. http://dx.doi.org/10.2208/jscejoe.76.2_i_480.
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