Blast-resistance analytical model for shallow-buried rigid structures based on one-dimensional wave theory and its experimental validations

Blast-induced ground shock is considered as the primary design load for underground protective structures, especially those that are shallow-buried. A shallow-buried rigid structure and its overlying soil are regarded as an equivalent structure supported on an elastic foundation and an analytical blast-resistant model based on one-dimensional wave theory is established. By solving the nonlinear wave equation with the separation of variables methods and orthogonal inner product methods, the standing wave solution for normal displacement at the soil-shallow buried rigid structure interface is derived, and the effects of load characteristics and structure-overlying soil compression wave ratio on the structural dynamic response are examined. Results indicate the dynamic displacement of shallow-buried structures can be expressed as the structural displacement yielded by static load being equivalent to peak blast load multiplied by a dynamic function according to one-dimensional wave theory. This method provides a justification for various experimental phenomena, achieves favorable calculation accuracy for underground structure with high rigid, and offers clear physical interpretation, making it well-suited for practical engineering applications. Amplification of structure dynamic response is observed with a shorter rise time and longer duration of blast load, indicating the significant influence of temporal parameters on the dynamic function. The dynamic response of shallow-buried structures is significantly influenced by the ratio of the compression wave between the structure and the ground layer, indicating that the dynamic behavior of the structure is determined by the capacity of the structure and soil to resist volumetric deformation. It is shown the relative errors between the analytical results and measured data for the solid pressure and the structural displacement are varied from 13.57% to 18.22% and from 9.86% to 13.22% respectively and thus the reliability and prediction accuracy of proposed model are validated. Consequently, it is demonstrated that the dynamic behavior of underground structures under blast loading can be reasonably depicted by the soil-structure interaction based on one-dimensional wave theory. The blast-resistance of such structures can be reasonably estimated by taking the interaction between soil and structure into account. It provides an effective tool for the analysis of shallow-buried.structure subjected to blast loading.