The classic trapdoor configuration has been useful to examine the changes in stresses expected on buried structures. However, the primary focus of previous studies has been on investigating the loads on the surface of the trapdoor, while stresses outside the trapdoor boundaries have generally been overlooked. This paper presents and discusses results of three-dimensional laboratory model tests conducted to investigate changes in the vertical soil pressure measured at various locations within a granular soil mass surrounding a deep rectangular trapdoor acting in both active and passive modes. The study aimed at investigating stress changes within the portion of the soil mass beyond the boundaries of the trapdoor. Redistributions of soil pressure were found to occur in a large zone of the soil outside the trapdoor under both active and passive conditions. Results indicate that active conditions induced the development of an unloading region in the soil, which includes the collapsing mass above the trapdoor and a portion of the soil surrounding the trapdoor. A stable load-transfer region could be identified in farther portions of the backfill. In passive conditions, the development of a load-transfer region above the trapdoor and an unloading region extending to farther zones in the backfill was also identified. The soil relative density, soil confinement and trapdoor shape were found to affect soil pressure distributions outside the trapdoor limits.

经典的活板门配置对于检查埋藏结构上预期的应力变化非常有用。但是，先前研究的主要重点是研究活板门表面的载荷，而活板门边界之外的应力通常被忽略了。本文介绍并讨论了三维实验室模型测试的结果，以研究在主动和被动模式下深矩形活板门周围的粒状土壤中不同位置测得的垂直土壤压力的变化。该研究旨在调查活板门边界以外的土壤质量部分的应力变化。发现在主动和被动条件下，土壤压力的重新分布都在活板门外的大面积土壤中发生。结果表明，活跃的条件导致土壤中卸载区域的发展，其中包括活板门上方塌陷的质量以及活板门周围的土壤的一部分。可以在回填物的较远部分中确定稳定的载荷传递区域。在被动条件下，还可以识别出活板门上方的载荷传递区域和延伸到回填区更远区域的卸载区域。发现土壤相对密度，土壤限制和活板门形状会影响活板门界限以外的土壤压力分布。其中包括活板门上方的塌陷物质和活板门周围的部分土壤。可以在回填物的较远部分中确定稳定的载荷传递区域。在被动条件下，还可以识别出活板门上方的载荷传递区域和延伸到回填区更远区域的卸载区域。发现土壤相对密度，土壤限制和活板门形状会影响活板门界限以外的土壤压力分布。其中包括活板门上方的塌陷物质和活板门周围的部分土壤。可以在回填物的较远部分中确定稳定的载荷传递区域。在被动条件下，还可以识别出活板门上方的载荷传递区域和延伸到回填区更远区域的卸载区域。发现土壤相对密度，土壤限制和活板门形状会影响活板门界限以外的土壤压力分布。还确定了活板门上方的载荷传递区域和延伸到回填区更远区域的卸载区域的发展。发现土壤相对密度，土壤限制和活板门形状会影响活板门界限以外的土壤压力分布。还确定了活板门上方的载荷传递区域和延伸到回填区更远区域的卸载区域的发展。发现土壤相对密度，土壤限制和活板门形状会影响活板门界限以外的土壤压力分布。