Ultimate bearing capacity of shallow foundations on sand with geogrid reinforcement

1993 ◽  
Vol 30 (3) ◽  
pp. 545-549 ◽  
Author(s):  
M.T. Omar ◽  
B.M. Das ◽  
V.K. Puri ◽  
S.C. Yen
Keyword(s):  
Bearing Capacity ◽  
Key Words ◽  
Model Test ◽  
Ultimate Bearing Capacity ◽  
Shallow Foundations ◽  
Shallow Foundation ◽  
Laboratory Model ◽  
Critical Depth ◽  
Test Results ◽  
Laboratory Model Test

Laboratory model test results for the ultimate bearing capacity of strip and square foundations supported by sand reinforced with geogrid layers have been presented. Based on the model test results, the critical depth of reinforcement and the dimensions of the geogrid layers for mobilizing the maximum bearing-capacity ratio have been determined and compared. Key words : bearing capacity, geogrid, model test, reinforced sand, shallow foundation.

Stabilization of Weak Clay with Strong Sand and Geogrid at Sand-Clay Interface

1998 ◽  
Vol 1611 (1) ◽  
pp. 55-62 ◽  
Author(s):  
Braja M. Das ◽  
Kim H. Khing ◽  
Eun C. Shin
Keyword(s):  
Bearing Capacity ◽  
Model Test ◽  
Soil Layer ◽  
Granular Soil ◽  
Laboratory Model ◽  
Test Results ◽  
Load Bearing Capacity ◽  
Load Bearing ◽  
Base Course ◽  
Granular Base

The load-bearing capacity of a weak clay subgrade can be increased by placing a strong granular base course of limited thickness on top of the clay layer. The load-bearing capacity can be increased further, or the thickness of the granular base course can be reduced, by separating both layers by a geogrid. Laboratory model test results for the ultimate bearing capacity of a rigid strip loading on the surface of a granular soil underlain by a soft clay with a layer of geogrid at the interface of the two soils are presented. The optimum thickness of the granular soil layer and the critical width of the geogrid layer required to derive the maximum benefit from the reinforcement were determined. Model test results on the permanent settlement of the rigid strip load caused by cyclic loading of low frequency are presented.

scholarly journals ULTIMATE RESISTANCE OF VERTICAL PLATE ANCHORS IN CLAY

1986 ◽  
Vol 1 (20) ◽  
pp. 134
Author(s):  
Braja M. Das ◽  
Miguel Picorness
Keyword(s):  
Model Test ◽  
Vertical Plate ◽  
Undrained Shear Strength ◽  
Laboratory Model ◽  
Test Results ◽  
Pullout Resistance ◽  
Saturated Clay ◽  
Parametric Relationship ◽  
Laboratory Model Test ◽  
Ultimate Resistance

Laboratory model test results for the ultimate pullout resistance of vertical square anchors embedded in saturated or near saturated clay have been presented. The undrained shear strength of the clay and the embedment ratio of the anchors have been varied. Based on the model test results, an empirical parametric relationship for estimation of the ultimate pullout resistance of shallow and deep square anchors has been presented.

Uplift behaviour of cylindrical anchors in sand

1998 ◽  
Vol 35 (1) ◽  
pp. 70-80 ◽  
Author(s):  
S T Hsu ◽  
H J Liao
Keyword(s):  
Numerical Analysis ◽  
Model Test ◽  
Substantial Contribution ◽  
Laboratory Model ◽  
Cylindrical Shape ◽  
Critical Depth ◽  
Pullout Capacity ◽  
Pullout Behaviour ◽  
Laboratory Model Test ◽  
Shaft Friction

A series of laboratory model tests and numerical analyses has been carried out to study the behaviour of vertically embedded cylindrical anchors in sand. Due to the cylindrical shape of the anchor, both the shaft friction and the end resistance have substantial contribution to the pullout capacity. But shaft friction and end resistance do not reach peak values at the same anchor displacement. As a result, analyzing the anchorage behaviour of cylindrical anchors is complicated. The pullout behaviour of the anchor is significantly influenced by the embedded depth. There exists a critical depth (about seven to eight times the anchor diameter D) which differentiates the behaviour of a deeply embedded cylindrical anchor from that of an anchor with shallow embedment. The complete load-displacement relationships for shallow and deep anchors can be simulated by the numerical analysis proposed herein. A minimum horizontal spacing of 10D is needed between neighbouring cylindrical anchors to be free of interference.Key words: cylindrical anchor, uplift behaviour, laboratory model test, numerical analysis, sand.

scholarly journals A NEW DESIGN EQUATION FOR PREDICTION OF ULTIMATE BEARING CAPACITY OF SHALLOW FOUNDATION ON GRANULAR SOILS

2014 ◽  
Vol 19 (Supplement_1) ◽  
pp. S78-S90 ◽  
Author(s):  
Ehsan Sadrossadat ◽  
Fazlollah Soltani ◽  
Seyyed Mohammad Mousavi ◽  
Seyed Morteza Marandi ◽  
Amir H. Alavi
Keyword(s):  
Bearing Capacity ◽  
Numerical Models ◽  
Ultimate Bearing Capacity ◽  
Prediction Performance ◽  
Shallow Foundations ◽  
Shallow Foundation ◽  
Granular Soils ◽  
Good Prediction ◽  
Design Equation ◽  
Statistical Measures

A major concern in design of structures is to provide precise estimations of ultimate bearing capacity of soil beneath their foundations. Direct determination of the bearing capacity of foundations requires performing expensive and time consuming laboratory tests. To cope with this issue, several numerical models have been presented by researchers. This paper presents the development of a new design equation for the prediction of the ultimate bearing capacity of shallow foundations on granular soils using linear genetic programming (LGP) methodology. The ultimate bearing capacity is formulated in terms of width of footing, footing geometry, depth of footing, unit weight of sand, and angle of shearing resistance. The LGP-based design equation is established using the results of several load tests on real sized foundations presented in the literature. Validity of the model is verified using a part of laboratory data that are not involved in the calibration process. The statistical measures of coefficient of determination, root mean squared error and mean absolute error are used to evaluate the performance of the model. Sensitivity and parametric analyses are conducted and discussed. The proposed model accurately characterizes the ultimate bearing capacity resulting in a very good prediction performance. The LGP model reaches a better prediction performance than the well-known prediction equations for the bearing capacity of shallow foundations.

Laboratory Model Test on Foundation Reinforcement by Locating Lime-Soil Pileat both Side of Strip Footing

2012 ◽  
Vol 170-173 ◽  
pp. 740-742
Author(s):  
Ji Zhou ◽  
Xi Yuan Liu ◽  
Yuan Ming Dou
Keyword(s):  
Bearing Capacity ◽  
Model Test ◽  
Similarity Theory ◽  
Strengthening Mechanism ◽  
Strip Footing ◽  
Laboratory Model ◽  
Before And After ◽  
S Curve ◽  
Laboratory Model Test

Using similarity theory as guidance ,the paper designs the laboratory model test on foundation reinforcement by locating lime-soil pile at both side of strip footing, and researches foundation bearing capacity, p-s curve, the magnitude and distribution discipline of the foundation stress before and after reinforcement, and analyzes the load-bearing mechanism, strengthening mechanism and reinforcement effect of the strengthening technology. The results show that the lime-soil pile can effectively improve the foundation bearing capacity, and reduce the amount of ground settlement; under the role of the lime-soil pile, the stress spread lesser to the outside of pile in the ground, and causes the foundation stress to the deeper place.

Bearing capacity of anisotropic cohesionless soils

1978 ◽  
Vol 15 (4) ◽  
pp. 592-595 ◽  
Author(s):  
G. G. Meyerhof
Keyword(s):  
Shear Strength ◽  
Bearing Capacity ◽  
Ultimate Bearing Capacity ◽  
Shallow Foundations ◽  
Test Results ◽  
Cohesionless Soils ◽  
Inclined Load ◽  
Load Tests

Previous test results of the anisotropic shear strength of cohesionless soils are reviewed. The theory of the ultimate bearing capacity of shallow foundations on homogeneous isotropic soils is extended to anisotropic cohesionless soils. The proposed method of analysis is compared with the results of some load tests on anisotropic sand. An extension of this method to foundations under inclined load is briefly discussed.

Sign in / Sign up

Export Citation Format

Share Document