Abstract

To propose a simplified semi-empirical method for predicting the additional stress on the underlying layer of the rigid pile-net composite foundation, a finite element analysis, which verified by a series of field tests and model tests, are carried out. Focusing on the equivalent entity method recommended by Technical code for composite foundation, the equivalent frictional resistance coefficient, which is a key factor affecting the additional stress, is deduced through the static balance theory and β-method. Finite element analyses, including 432 tests, are conducted to analyse the effect of pile length, pile spacing, thickness of cushion layer, embankment height and geological conditions on the key coefficient. Then, a simplified semi-empirical model for predicting the key coefficient as well as the additional stress is proposed based on numerical results. The accuracy of the proposed model is verified by the good agreement between the experimental results and numerical results.

摘要

为提出一种简化的半经验预测刚性桩网复合地基下垫层附加应力的方法，进行了有限元分析，并通过一系列现场试验和模型试验验证。围绕复合地基技术规范推荐的等效实体法，通过静平衡理论和β-推导了影响附加应力的关键因素等效摩擦阻力系数。方法。通过有限元分析，包括432次试验，分析了桩长、桩距、垫层厚度、路堤高度和地质条件对关键系数的影响。然后，基于数值结果，提出了一种预测关键系数和附加应力的简化半经验模型。实验结果与数值结果吻合良好，验证了所提模型的准确性。