In urban area tunnelling projects, preventing the adverse effects of tunnel construction on nearby structures often involves the use of embedded walls or piles. Designing the key parameters of these embedded structures is challenging due to the complex interaction between the soil and the structure. This paper presents a numerical investigation into the effects of embedded wall bending stiffness and soil-wall interface roughness on tunnel-wall interaction in sandy ground. Three dimensional numerical models were developed to simulate tunnel construction near an embedded wall with varying parameters, with sand behaviour simulated using a hypoplastic constitutive model calibrated by element tests and centrifuge models. The findings reveal that a decrease in interface roughness enhances the wall’s effectiveness in reducing tunnelling-induced settlements, while a decrease in wall bending stiffness reduces its performance in mitigating surface settlements and increases the wall bending moment. Based on the results, an improved design chart was developed by introducing correction coefficients for wall depth, taking into account the effects of wall stiffness and interface roughness on the wall’s efficiency in reducing tunnelling-induced settlements. This chart aims to assist engineers in quickly determining the preliminary horizontal locations and depths of embedded walls, ensuring both safety and effectiveness in selecting the depth and horizontal position of the embedded wall relative to the tunnel. These findings provide valuable guidance for the practical design and implementation of protective measures in urban excavation projects.

中文翻译：

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弯曲刚度和界面粗糙度对隧道-埋埋墙相互作用的影响


在城市地区的隧道工程中，防止隧道施工对附近结构的不利影响通常涉及使用预埋墙或桩。由于土壤和结构之间的复杂相互作用，设计这些嵌入式结构的关键参数具有挑战性。本文对砂土中嵌入墙体弯曲刚度和土-墙界面粗糙度对隧道-墙相互作用的影响进行了数值研究。开发了三维数值模型来模拟具有不同参数的埋设墙附近的隧道施工，并使用通过元素测试和离心机模型校准的不塑性本构模型模拟沙子行为。研究结果表明，界面粗糙度的降低增强了墙体减少隧道引起的沉降的有效性，而墙体弯曲刚度的降低降低了其减轻表面沉降的性能并增加了墙体弯矩。根据结果，通过引入墙体深度的修正系数开发了一个改进的设计图表，同时考虑了墙体刚度和界面粗糙度对墙体减少隧道引起的沉降效率的影响。该图表旨在帮助工程师快速确定预埋墙的初步水平位置和深度，确保安全有效地选择预埋墙相对于隧道的深度和水平位置。研究结果为城市基坑工程防护措施的实际设计和实施提供了有价值的指导。