It is known that the distribution of active earth pressure against a translating rigid wall is not triangular but nonlinear, owing to arching effects in the backfill. In the present paper, a new formulation is proposed for calculating the active earth pressure on a rigid retaining wall undergoing horizontal translation. It takes into account the arching effects that occur in the backfill (or retained soil mass). In order to check the accuracy of the proposed formulation, the predictions from the equation are compared with both existing full-scale test results and values from existing equations. The comparisons between calculated and measured values show that the proposed equations satisfactorily predict both the earth pressure distribution and the lateral active earth force on the translating wall. In order to facilitate calculation of active earth pressures using the proposed equations, a modified active pressure coefficient and an effective height of application of the lateral active force are also prov...

Estimation of active earth pressure against rigid retaining walls considering arching effects

This paper presents a generalized approach for predicting the diameter of jet grout columns based on the theoretical framework of turbulent kinematic flow and soil erosion. The proposed calculation method is applicable to all conventional jet-grouting systems and takes into account the full range of operational parameters, fluid properties, soil strength, and particle size distribution, including the effect of the injection time on erosion distance. It was demonstrated that the increase in the jet grout column diameter arising from the use of a compressed air shroud in the double and triple fluid systems is approximately 27–81% for the typical range of air pressure of 0.5–1.5 MPa. The proposed method was applied to four case histories involving four variants of jet-grouting systems, i.e., single fluid, double fluid, triple fluid, and an enhanced triple fluid system. Comparison between the calculated and the measured jet grout column diameters indicated that the proposed method can produce reasonab...

Generalized Approach for Prediction of Jet Grout Column Diameter

Current seismic design of bridges is based on a displacement performance philosophy using nonlinear static pushover analysis. This type of bridge design necessitates that the geotechnical engineer predict the resistance of the abutment backfill soils, which is inherently nonlinear with respect to the displacement between soil backfill and the bridge structure. This paper employs limit-equilibrium methods using mobilized logarithmic-spiral failure surfaces coupled with a modified hyperbolic soil stress-strain behavior (LSH model) to estimate abutment nonlinear force-displacement capacity as a function of wall displacement and soil backfill properties. The calculated force-displacement capacity is validated against the results from eight field experiments conducted on various typical structure backfills. Using LSH and experimental data, a simple hyperbolic force-displacement (HFD) equation is developed that can provide the same results using only the backfill soil stiffness and ultimate soil capacity. HFD is compatible with current CALTRANS practice in regard to the seismic design of bridge abutments. The LSH and HFD models are powerful and effective tools for practicing engineers to produce realistic bridge response for performance-based bridge design.

Nonlinear Soil-Abutment-Bridge Structure Interaction for Seismic Performance-Based Design

In this paper the writers first present experimental results obtained for the distribution of the active stresses due to a sand backfill behind a rigid wall rotating about the top. The experimental evidence shows that the stress distribution is nonlinear and that, due to arching, the stress near the top of the wall increases beyond the level of the at‐rest stress. Consequently, the point of application of the lateral thrust is much higher than one‐third from the wall base. Arching effects increase with increasing soil density. Secondly, comparisons of the active earth pressure distributions are made for three different wall movement modes: (1) Rotation about top; (2) rotation about heel; and (3) translation. Total active resultant forces and the points of application of these forces are summarized.

Static earth pressures with various wall movements

Written by a leader on the subject, Introduction to Geotechnical Engineering is first introductory geotechnical engineering textbook to cover both saturated and unsaturated soil mechanics. Destined to become the next leading text in the field, this book presents a new approach to teaching the subject, based on fundamentals of unsaturated soils, and extending the description of applications of soil mechanics to a wide variety of topics. This groundbreaking work features a number of topics typically left out of undergraduate geotechnical courses.

Geotechnical Engineering: Unsaturated and Saturated Soils

This paper presents experimental data of earth pressure acting against a vertical rigid wall, which moved into a mass of dry sand with a stress‐free horizontal surface under various wall‐movement modes. To investigate the variation of earth pressure induced by the rotation about a point above the top (RTT) and rotation about a point below the wall base (RBT) types of wall movement, the instrumented retaining‐wall facility was developed at National Chiao Tung University. Based on experimental data it is found that, for a wall under translational movement, the passive pressure distribution is linear and in good agreement with Terzaghi's prediction based on the general wedge theory. For a wall under either RTT or RBT mode, the magnitude of passive thrust and its point of application are significantly affected by the mode of wall displacement. However, if the parameter n indicating location of the center of rotation is greater than 2.0, the influence of movementmode on passive earth pressure becomes less impo...

https://ir.nctu.edu.tw:443/bitstream/11536/2389/1/A1994NY90900002.pdf

Passive earth pressures with various wall movements

This paper presents experimental data of earth pressure acting against a vertical rigid wall, which moved toward a mass of dry sand. The backfill had been placed in lifts to achieve relative densities of 38, 63, and 80%. The instrumented retaining-wall facility at National Chiao Tung University in Taiwan was used to investigate the effects of soil density on the development of earth pressure. Based on the experimental data, it has been found that the Coulomb and Terzaghi solutions calculated with the peak internal friction angle significantly overestimated the ultimate passive thrust for the retaining wall filled with dense sand. As the wall movementS exceeded 12% of the wall height H, the passive earth thrust would reach a constant value, regardless of the initial density of backfill. Under such a large wall movement, soils along the rupture surface had reached the critical state, and the shearing strength on the surface could be properly represented with the residual internal-friction angle. The ultimate passive earth pressure was successfully estimated by adopting the critical state concept to either Terzaghi or Coulomb theory. CE Database keywords: Passive pressure; Earth pressure; Sand; Vertical angles.

https://ir.nctu.edu.tw:443/bitstream/11536/28626/1/000177170600003.pdf

Passive Earth Pressure with Critical State Concept

https://ir.nctu.edu.tw:443/bitstream/11536/32017/1/000285220300021.pdf

Numerical solution of active earth pressures on rigid retaining walls built near rock faces

This paper reports on the magnitudes and distribution of static atrest stresses behind a rigid wall as a function of soil densification and on static active stresses mobilized behind a rigid wall r...

Yung-Show Fang

Papers

Static earth pressures with various wall movements

Passive earth pressures with various wall movements

Passive Earth Pressure with Critical State Concept

Numerical solution of active earth pressures on rigid retaining walls built near rock faces

KA and Ko behind rotating and non-yielding walls