Lateral earth pressure

About: Lateral earth pressure is a research topic. Over the lifetime, 5334 publications have been published within this topic receiving 62552 citations.

Predicting the Earth Pressure on Integral Bridge Abutments

Abstract: The soil adjacent to integral bridge abutments experiences daily and annual temperature-induced cyclic loading due to expansion and contraction of the bridge deck. This causes a particular soil response and complicated soil-structure interaction problem, with considerable uncertainties in design. This paper describes a method of calculating the effects of thermal cycling by using the results of laboratory cyclic stress path testing within a numerical model. Samples of stiff clay and sand were tested in the triaxial apparatus under stress paths typical for behind an integral abutment. Distinct behavior was observed for the two soils, with stiff clay showing relatively little buildup of lateral stress with cycles, whereas for sand stresses continued to increase, exceeding at-rest and approaching full passive pressures. To explore the implications of these findings on the soil-abutment interaction and to estimate the lateral stresses acting on the abutment as a whole, a numerical (finite difference) model was developed with a soil model reproducing the sand behavior at element level. The numerical model gave good agreement with published centrifuge and field data, and indicated that the stress profile specified in some current standards is conservative. Influence of abutment stiffness and wall friction is also quantified.

Earthquake-Induced Lateral Soil Pressures on Structures

Abstract: Based on the behavior of backfill soil, the state of knowledge reflects three design approaches: elastic solutions, elasto-plastic solutions and fully plastic (static) solutions. The major differences in the fully plastic solutions utilizing Mononobe-Okabe's approach have been with the application point of the resultant force. Plastic solutions do not consider soil-structure interaction effects and are based on rigid body motions. Elastic dynamic solutions are proposed that provide guidelines to estimate backfill pressures for small lateral displacements. Solutions are also provided to estimate dynamic pore-water pressures. The study of these papers indicates that there is a general lack of a comprehensive treatment of the subject and there is a need for further investigations in the following areas for the dynamic case: passive soil pressures; elasto-plastic backfill soil models; soil-structure interaction effects; mixed soils; surcharge effects; and wall stability for combined bearing, sliding, and overturning.

Numerical Study of an Integral Abutment Bridge Supported on Drilled Shafts

Abstract: The majority of integral abutment bridges (IABs) in the United States are supported on steel H-piles to provide the flexibility necessary to minimize the attraction of large lateral loads to the foundation and abutment. In Hawaii, steel H-piles have to be imported, corrosion tends to be severe in the middle of the Pacific Ocean, and the low buckling capacity of steel H-piles in scour-susceptible soils has led to a preference for the use of concrete deep foundations. A drilled shaft-supported IAB was instrumented to study its behavior during and after construction over a 45-month period. This same IAB was studied using the finite-element method (FEM) in both two- (2D) and three dimensional (3D). The 3D FEM yields larger overall pile curvature and moments than 2D because in 3D, the high plasticity soil is able to displace in between the drilled shafts thereby “dragging” the shafts to a more highly curved profile while soil flow is restricted by plane strain beam elements in 2D. Measured drilled shaft axial ...

Calculation of Passive Pressure in Sand

Abstract: Experimental investigations of passive earth pressures in sand show that current theoretical solutions overestimate failure loads and give incorrect stress distributions. Plasticity analysis has been used to examine the effects of changes in boundary friction and rotation preceding failure. Solutions have been developed to determine the magnitude of the scale effect due to the angle of shearing resistance of the sand varying with stress level in the failure zone. By assuming that the lower 30% of the wall does not reach plastic failure stresses, an assumption suggested by a recent experimental investigation, values of passive pressure coefficient Kp have been calculated, which agree well with experimental values over a wide range of sand densities.

Difference between Load-Transfer Relationships for Laterally Loaded Pile Groups: Active p - y or Passive p -δ

Abstract: Two-dimensional (2D) finite-element analyses were carried out to study undrained soil deformation around piles displaced laterally through soil. The load-transfer p - curves produced were found to ...