考虑竖向土拱的桩锚与土钉的联合支护

Retaining structures combined pile-anchor with soil nails considering vertical soil arch

在对桩锚支护结构进行研究时,以降低工程造价为出发点,引入了竖向土拱的概念。通过对土拱的形成机制进行分析,将其承受的荷载进行了简化。在此基础上推导出了土拱是位于锚杆和坑底之间的半个椭圆。通常情况下,椭圆的长轴在竖向,长短轴之比取决于锚杆的相对位置和土层的参数。由此,根据已建立的竖向土拱理论,研究了在桩锚支护结构中如何设置土钉的问题。研究结果可以用来指导桩锚支护结构的工程设计,并对多支点支护结构的局部土压力、锚杆和土钉的联合支护等问题的进一步研究提供参考。

The concept of the vertical soil arch was brought forward to study the pile-anchor retaining structures in order to reduce the construction cost. The loads on the soil arch were simplified by analyzing the mechanism of soil arch. It was deduced that the soil arch was half an ellipse located between the anchor and the bottom of the foundation pit. Usually, the longer axis is in the vertical direction, and the proportion between the longer axis and the shorter is determined on the anchor relative location and the soil property. Hence, the problem how to design the soil nail was studied, and the conclusion could be helpful to the actual design for pile-anchor retaining structures and to the further researches on the local earth pressures of multiprurpose retaining structures, combined retaining with anchor and soil nail, etc.