In this paper, we propose a three-dimensional finite element model that can simulate the caisson foundation behavior in gravelly soil. The soil model adopts a combination of the porous elastic model and the modified Drucker–Prager/Cap model for simulating the gravelly soil. For avoiding problems in laboratory testing on gravel specimens, a practical approach is proposed to determine and calibrate the parameters of the soil model using results of field geotechnical tests, such as a shear wave velocity profile, strength parameters of direct shear tests, and pressure–displacement curves of vertical and horizontal plate loading tests. The proposed finite element model was applied to simulate in situ lateral load tests on bridge caisson foundations in gravelly soil. Using the calibrated soil model, responses of caisson displacement, caisson head rotation, and soil displacement analyzed were observed to be in agreement with the measured responses. Caisson and surrounding soil responses were also investigated in detail.

在本文中，我们提出了一个三维有限元模型，可以模拟砾石土中沉箱基础的行为。土壤模型采用了多孔弹性模型和改进的Drucker-Prager / Cap模型的组合来模拟砾石土壤。为了避免在砾石标本的实验室测试中出现问题，提出了一种实用的方法来确定和校准土壤模型的参数，方法是使用现场岩土工程的结果，例如剪切波速度剖面，直接剪切试验的强度参数以及压力–垂直和水平板载荷试验的位移曲线。提出的有限元模型被用于模拟砾石土壤中桥梁沉箱基础的现场侧向荷载试验。使用校正后的土壤模型，沉箱位移的响应，沉箱头部旋转和土壤位移分析与实测结果一致。沉箱和周围的土壤反应也进行了详细研究。