Distribution of lateral pressure of unbound soil in calculations of flexible retaining structures depending on their deformations

Introduction. The most commonly used methods for designing flexible retaining walls and shoring of excavations are the ones based on classical theories. Such approaches assume a linear or piecewise linear distribution of active earth pressure. However, real retaining structures under load are subject to deformation, which significantly affects the redistribution of lateral earth pressure along the wall height within the collapse prism. The article discusses the verification of the previously proposed inclined block method, that considers the redistribution of lateral earth pressure and calculates flexible retaining structures taking into account the actual occurrence of stress-strain state in the soil mass. Practical recommendations for its application are provided.

Aim. To verify a new numerical analysis method for determining lateral earth pressure along with developing practical recommendations regarding its redistribution in the active zone for flexible retaining structures.

Materials and methods. Calculated data obtained using the proposed inclined block method were thoroughly compared with experimental research results. An algorithm was developed for applying correction factors that take into account lateral pressure redistribution, with demonstrations using specific calculation examples.

Results. High correspondence between calculated and experimental data on lateral earth pressure distribution has been established. Minor differences between the calculated and experimental values can be explained by the influence of friction forces at the wall–soil interface. As a comparison, the difference between the calculations using the correction factor tables and the inclined block method (implemented in specialized software) is less than 3 %, which verifies the reliability of the proposed approach.

Conclusions. The results obtained indicate the efficacy of the proposed inclined block method for calculating the pressure on flexible retaining structures with upper strut fastenings depending on their deformations. A comparative analysis of experimental data with calculated results showed a high degree of correspondence in the distribution of lateral earth pressure. The practical recommendations developed thus enable the redistribution of lateral pressure to be taken into account with sufficient accuracy without the use of complex geotechnical software packages, which considerably simplifies engineering calculations.

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