Effect of pile driving on adjacent piles in clay

1994 ◽  
Vol 31 (6) ◽  
pp. 856-867 ◽  
Author(s):  
H.G. Poulos
Keyword(s):  
Structural Damage ◽  
Tensile Failure ◽  
Pile Driving ◽  
Bending Moments ◽  
Depth Of Penetration ◽  
Vertical Movements ◽  
Concrete Piles ◽  
Axial Forces ◽  
Model Pile ◽  
Soil Movements

When a pile is driven into clay, horizontal and vertical movements are developed in the soil surrounding the pile. These movements will tend to develop axial forces and bending moments in adjacent piles that have already been installed. Possible consequences for these piles are (i) structural damage or cracking (of concrete piles) arising from the induced bending moments, (ii) tensile failure of the piles due to the induced axial forces, and (iii) lifting-off of the pile tip from the bearing stratum due to the axial induced movements. This paper describes the results of a theoretical analysis of the bending moments and axial forces developed in a pile due to driving of an adjacent pile in clay. The analysis uses approximate distributions of horizontal and vertical soil movements caused by pile driving, developed from a "strain-path" analysis, together with inferences from model pile test data. An examination is made of various factors that may influence the induced bending moments and forces, including pile spacing, depth of penetration of the adjacent pile, and number of piles driven. For a number of published case histories comparisons are made between theoretical and measured axial and lateral pile movements. In general, satisfactory agreement is found. Key words : foundations, lateral movements, pile driving, settlement, soil displacement.

scholarly journals Driven Pile Effects on Nearby Cylindrical and Semi-Tapered Pile in Sandy Clay

2021 ◽  
Vol 11 (7) ◽  
pp. 2919
Author(s):  
Massamba Fall ◽  
Zhengguo Gao ◽  
Becaye Cissokho Ndiaye
Keyword(s):  
Coupling Effect ◽  
Lateral Displacement ◽  
Bending Moment ◽  
Adaptive Mesh ◽  
Pile Driving ◽  
Arbitrary Lagrangian Eulerian ◽  
Axial Forces ◽  
Tapered Pile ◽  
Driven Pile ◽  
The Impact

A pile foundation is commonly adopted for transferring superstructure loads into the ground in weaker soil. They diminish the settlement of the infrastructure and augment the soil-bearing capacity. This paper emphases the pile-driving effect on an existing adjacent cylindrical and semi-tapered pile. Driving a three-dimensional pile into the ground is fruitfully accomplished by combining the arbitrary Lagrangian–Eulerian (ALE) adaptive mesh and element deletion methods without adopting any assumptions that would simplify the simulation. Axial forces, bending moment, and lateral displacement were studied in the neighboring already-installed pile. An investigation was made into some factors affecting the forces and bending moment, such as pile spacing and the shape of the already-installed pile (cylindrical, tapered, or semi-tapered). An important response was observed in the impact of the driven pile on the nearby existing one, the bending moment and axial forces were not negligible, and when the pile was loaded, it was recommended to consider the coupling effect. Moreover, the adjacent semi-tapered pile was subjected to less axial and lateral movement than the cylindrical one with the same length and volume for taper angles smaller than 1.0°, and vice versa for taper angles greater than 1.4°.

scholarly journals 3-D Numerical Study of Mechanical Behaviors of Pile-Anchor System

2014 ◽  
Vol 580-583 ◽  
pp. 238-242
Author(s):  
Ri Cheng Liu ◽  
Bang Shu Xu ◽  
Bo Li ◽  
Yu Jing Jiang
Keyword(s):  
Simulation Analysis ◽  
Numerical Study ◽  
Bending Moments ◽  
Mechanical Behaviors ◽  
Foundation Pit ◽  
Anchor System ◽  
Anchor Cable ◽  
Axial Forces ◽  
Toppling Failure ◽  
Potential Failure

Mechanical behaviors of pile-soil effect and anchor-soil effect are significantly important in supporting engineering activities of foundation pit. In this paper, finite difference method (FDM) was utilized to perform the numerical simulation of pile-anchor system, composed of supporting piles and pre-stressed anchor cables. Numerical simulations were on the basis of the foundation pit of Jinan’s West Railway Station, and 3D simulation analysis of foundation pit has been prepared during the whole processes of excavation, supporting and construction. The paper also analyzed the changes of bending moments of piles and axial forces of cables, and discussed mechanical behaviors of pile-anchor system, through comparisons with field monitoring. The results show that the parameters concluding vertical gridding’s number, cohesion of pile and soil, and pile stiffness have robust influences on supporting elements’ behaviors. Mechanical behaviors of supporting pile and axial forces of anchor cable changed dramatically, indicating that the potential failure form was converted from toppling failure to sliding failure.

Stiffened Hangers: an Often Overlooked Tool for Conceptual Design of Tied-Arch Footbridges

2021 ◽  
Author(s):  
Juan José Jorquera-Lucerga ◽  
Juan Manuel GARCÍA-GUERRERO
Keyword(s):  
Low Cost ◽  
Three Dimensional ◽  
Structural Response ◽  
Bending Moments ◽  
Structural Element ◽  
Axial Forces ◽  
Limited Effectiveness ◽  
Out Of Plane ◽  
Arch Bridges ◽  
Fixed End

<p>In tied-arch bridges, the way the arch and the deck are connected may become crucial. The deck is usually suspended from hangers made out of steel pinned cables capable of resisting axial forces only. However, a proper structural response, (both in-plane and out-of-plane) may be ensured by fixing and stiffening the hangers in order to resist, additionally, shear forces and bending moments. This paper studies the effect of different pinned and stiffened hanger arrangements on the structural behavior of the tied-arch footbridges, with the intention of providing designers with useful tools at the early steps of design. As a major conclusion, regarding the in-plane behavior, hangers composed of cables (either with vertical, Nielsen-Löhse or network arrangements) are recommended due to its low cost and ease of erection. Alternatively, longitudinally stiffened hangers, fixed at both ends, can be used. Regarding the out-of-plane behavior, and in addition to three-dimensional arrangements of cables, of limited effectiveness, transversally stiffened hangers fixed at both ends are the most efficient arrangement. A configuration almost as efficient can be achieved by locating a hinge at the end corresponding to the most flexible structural element (normally the arch). Its efficiency is further improved if the cross-section tapers from the fixed end to the pinned end.</p>

Analytical Computational Models for Relationship between Ultimate Bending Moment of Concrete Segments and Axial Force

2020 ◽  
Vol 853 ◽  
pp. 177-181
Author(s):  
Zhi Yun Wang ◽  
Shou Ju Li
Keyword(s):  
Numerical Simulation ◽  
Computational Model ◽  
Axial Force ◽  
Computational Models ◽  
Plane Deformation ◽  
Bending Moment ◽  
Analytical Models ◽  
Bending Moments ◽  
Axial Forces ◽  
Practical Engineering

Concrete segments are widely used to support soil and water loadings in shield-excavated tunnels. Concrete segments burden simultaneously to the loadings of bending moments and axial forces. Based on plane deformation assumption of material mechanics, in which plane section before bending remains plane after bending, ultimate bending moment model is proposed to compute ultimate bearing capacity of concrete segments. Ultimate bending moments of concrete segments computed by analytical models agree well with numerical simulation results by FEM. The accuracy of proposed analytical computational model for ultimate bending moment of concrete segments is numerically verified. The analytical computational model and numerical simulation for a practical engineering case indicate that the ultimate bending moment of concrete segments increases with increase of axial force on concrete segment in the case of large eccentricity compressive state.

Responses of single piles to tunneling-induced soil movements in sandy ground

2007 ◽  
Vol 44 (10) ◽  
pp. 1224-1241 ◽  
Author(s):  
Kuo-Hui Chiang ◽  
Chung-Jung Lee
Keyword(s):  
Load Transfer ◽  
Bending Moment ◽  
Test Results ◽  
Axial Forces ◽  
Depth Ratio ◽  
Sandy Ground ◽  
Single Piles ◽  
Pile Settlement ◽  
Ground Loss ◽  
Soil Movements

The responses of single piles under various working loads to nearby tunneling were investigated using centrifuge model tests. First, the tunneling-induced soil movements and the tunnel stability in saturated sandy ground were examined. Two instrumented piles with penetration depths of 27 m were located either side of, and at various distances from, tunnels embedded at depths with various cover-to-diameter ratios, and used to measure the bending moments and axial forces at various depths for various ground loss ratios during tunneling simulations. The test results show that in the case of shallow tunneling near a long pile the unit skin frictions on the pile from the tunnel axis to an elevation of 1.5 tunnel diameters above the tunnel axis rapidly decrease with increases in the ground loss ratio. A significant degradation of the end bearing capacity results in a large settlement of the pile if the pile tip is near the tunnel. The depth ratio was found to be a significant influence on the bending moment profiles along the piles, but both the depth ratio and the working loads on the pile head determine the axial load profile and the pile settlement. A mechanism for pile load transfer during new tunneling is proposed to enable construction engineers to prevent structure failure in piles and excessive pile settlement.

scholarly journals Mechanical signals at the base of a rat vibrissa: the effect of intrinsic vibrissa curvature and implications for tactile exploration

2012 ◽  
Vol 107 (9) ◽  
pp. 2298-2312 ◽  
Author(s):  
Brian W. Quist ◽  
Mitra J. Z. Hartmann
Keyword(s):  
Concave Side ◽  
Bending Moments ◽  
Intrinsic Curvature ◽  
Natural Behavior ◽  
Axial Forces ◽  
Detailed Surface ◽  
Increased Sensitivity ◽  
Mystacial Vibrissae ◽  
Almost All

Rats actively tap and sweep their large mystacial vibrissae (whiskers) against objects to tactually explore their surroundings. When a vibrissa makes contact with an object, it bends, and this bending generates forces and bending moments at the vibrissa base. Researchers have only recently begun to quantify these mechanical variables. The present study quantifies the forces and bending moments at the vibrissa base with a quasi-static model of vibrissa deflection. The model was validated with experiments on real vibrissae. Initial simulations demonstrated that almost all vibrissa-object collisions during natural behavior will occur with the concave side of the vibrissa facing the object, and we therefore paid particular attention to the role of the vibrissa's intrinsic curvature in shaping the forces at the base. Both simulations and experiments showed that vibrissae with larger intrinsic curvatures will generate larger axial forces. Simulations also demonstrated that the range of forces and moments at the vibrissal base vary over approximately three orders of magnitude, depending on the location along the vibrissa at which object contact is made. Both simulations and experiments demonstrated that collisions in which the concave side of the vibrissa faces the object generate longer-duration contacts and larger net forces than collisions with the convex side. These results suggest that the orientation of the vibrissa's intrinsic curvature on the mystacial pad may increase forces during object contact and provide increased sensitivity to detailed surface features.

Sign in / Sign up

Export Citation Format

Share Document