Ultimate Soil Pressures for Pile Groups in Soft Clay Subjected to Lateral Soil Movements

2008 ◽  
Vol 2 (1) ◽  
pp. 42-51 ◽  
Author(s):  
L. F. Miao ◽  
A.T.C. Goh ◽  
K.S. Wong ◽  
C.I. Teh
Keyword(s):  
Soft Clay ◽  
Pile Groups ◽  
Soil Movements

Time-dependent behavior of pile groups by staged construction of an adjacent embankment on soft clay

2004 ◽  
Vol 41 (4) ◽  
pp. 644-656 ◽  
Author(s):  
Sangseom Jeong ◽  
Donghee Seo ◽  
Jinhyung Lee ◽  
Joogbai Park
Keyword(s):  
Soft Clay ◽  
Time Dependent ◽  
Bending Moments ◽  
Pile Groups ◽  
Centrifuge Model ◽  
Surcharge Loading ◽  
Short And Long Term ◽  
Centrifuge Model Tests ◽  
Soil Movements

A series of centrifuge model tests were performed to investigate the behavior of pile groups subjected to lateral soil movements by surcharge loading from approach embankments. The emphasis was on quantifying the time-dependent response in terms of deflections, bending moments, and earth pressures acting on pile groups during embankment construction and over short- and long-term periods after embankment construction. A variety of instruments were used to examine the soil–pile interaction for pile groups adjacent to surcharge loads. Through these studies, it is found that pile cap deflections and bending moments developed to their maximum values under the short-term surcharge loading and decreased gradually to minimum values under the long-term loading. The ground settlement reached its maximum value under long-term loading, however, due to the consolidation of soft clay. It is also found that the lateral mean pressure acting on the pile is about 0.75 and 0.35 times the surcharge load q (= γH, where γ is the unit weight of the soil and H is the height of the embankment) under short- and long-term loading, respectively.Key words: time-dependent response, lateral soil movements, pile groups, centrifuge model tests, surcharge loads, soft clay.

scholarly journals Numerical Study of Laterally Loaded Piles in Soft Clay Overlying Dense Sand

2021 ◽  
Vol 7 (4) ◽  
pp. 730-746
Author(s):  
Amanpreet Kaur ◽  
Harvinder Singh ◽  
J. N. Jha
Keyword(s):  
Layer Thickness ◽  
Soft Clay ◽  
Bending Moment ◽  
Layered Soil ◽  
Clay Layer ◽  
Pile Groups ◽  
Dense Sand ◽  
Lateral Capacity ◽  
Laterally Loaded ◽  
Pile Length

This paper presents the results of three dimensional finite element analysis of laterally loaded pile groups of configuration 1×1, 2×1 and 3×1, embedded in two-layered soil consisting of soft clay at liquid limit overlying dense sand using Plaxis 3D. Effects of variation in pile length (L) and clay layer thickness (h) on lateral capacity and bending moment profile of pile foundations were evaluated by employing different values of pile length to diameter ratio (L/D) and ratio of clay layer thickness to pile length (h/L) in the analysis. Obtained results indicated that the lateral capacity reduces non-linearly with increase in clay layer thickness. Larger decrease was observed in group piles. A non-dimensional parameter Fx ratio was defined to compare lateral capacity in layered soil to that in dense sand, for which a generalized expression was derived in terms of h/L ratio and number of piles in a group. Group effect on lateral resistance and maximum bending moment was observed to become insignificant for clay layer thickness exceeding 40% of pile length. For a fixed value of clay layer thickness, lateral capacity and bending moment in a single pile increased significantly with increase in pile length only up to an optimum embedment depth in sand layer which was found to be equal to three times pile diameter and 0.21 times pile length for pile with L/D 15. Scale effect on lateral capacity has also been studied and discussed. Doi: 10.28991/cej-2021-03091686 Full Text: PDF

Behaviour of friction piles in soft sensitive clays

1980 ◽  
Vol 17 (2) ◽  
pp. 203-224 ◽  
Author(s):  
R. Blanchet ◽  
F. Tavenas ◽  
R. Garneau
Keyword(s):  
Precast Concrete ◽  
Soft Clay ◽  
Load Test ◽  
Pile Groups ◽  
Test Program ◽  
Shear Creep ◽  
Soft Clays ◽  
The North ◽  
Effective Stress Analysis

During the construction of heavy structures, such as bridges and overpasses, on soft clays on the north shore of the St. Lawrence Valley, a detailed load test program on friction piles was performed to establish the characteristics of the most suitable type of pile and to study its long-term behaviour. Three types of piles, timber, steel pipe with closed end, and precast concrete Herkules H-420 piles, were tested. Four timber piles driven in a group and submitted to a 712 kN load served to study the long-term settlement of a small group of piles. Three deep settlement gauges were installed in the centre of this group for measuring settlements in clay at various depths.This test program was completed by the instrumentation of two bridge piers in order to verify the behaviour of larger groups of piles.The paper presents the results of the test piles, the long-term behaviour (4 years) of the bridge pier foundations resting on friction piles in soft clay, and the interpretation of the results.This study shows that the pore pressures induced by pile driving are related to the pre-consolidation of the clay and that they are much larger for tapered piles. It is demonstrated that the effective stress analysis method proposed in 1976 by Meyerhof determines adequately the ultimate pile bearing capacity, but that the effect of the timber pile taper doubles the skin friction.The settlement analysis of pile groups shows that settlements are due to the reconsolidation of the clay and shear creep deformations in the clay close to the pile wall.

scholarly journals Discussion: Design of piled bridge abutments on soft clay for loading from lateral soil movements

Géotechnique ◽  
1996 ◽  
Vol 46 (1) ◽  
pp. 165-173 ◽  
Author(s):  
D. P. Stewart ◽  
R. J. Jewell ◽  
M. F. Randolph
Keyword(s):  
Soft Clay ◽  
Bridge Abutments ◽  
Soil Movements

Negative skin friction from surface settlement measurements in model group tests

1995 ◽  
Vol 32 (6) ◽  
pp. 1075-1079 ◽  
Author(s):  
Mehmet Ufuk Ergun ◽  
Devrim Sönmez
Keyword(s):  
Soft Clay ◽  
Soil Surface ◽  
Pile Group ◽  
Friction Model ◽  
Model Group ◽  
Pile Groups ◽  
Negative Skin Friction ◽  
Dense Sand ◽  
Model Study ◽  
Negative Friction

Groups of model wood piles driven to end bearing through dense sand over soft clay were used to determine the relative settlement of the soil surface inside and outside the groups as the soil was compressed by air pressure. Square 30 mm piles at spacings of 2 to 6 times the pile width were used in groups of 3 × 3, 4 × 4, and 5 × 5. The results indicate that pile group effects were negligible at pile spacings at 5 to 6 pile widths. Key words : negative friction, model study, pile groups, sand.

Field Tests Of The Lateral-Load Behavior Of Pile Groups In Soft Clay

1980 ◽  
Author(s):  
Hudson Matlock ◽  
Wayne B. Ingram ◽  
Allen E. Kelley ◽  
Dewaine Bogard
Keyword(s):  
Soft Clay ◽  
Field Tests ◽  
Lateral Load ◽  
Pile Groups ◽  
Load Behavior
Sign in / Sign up

Export Citation Format

Share Document