土钉支护面层受力探讨

Forces acting on surface of soil nailing supports

土钉墙面层受不受力一直存在着争议。根据规程可知土钉面层不受力,所以喷射混凝土面层一般按构造进行设计。但实际上土钉墙面层土压力对基坑变形及墙体的应力分布有重要影响,特别是在软弱土地层深基坑中,面层受力较大。在提出有效下滑力概念的前提下,并结合增量法,对滑楔平衡法进行了改进。通过这种复合型算法计算得出土钉面层是受力的,并和实测值进行了比较,结果表明这种计算方法贴近实际情况。

Whether or not the forces act on the surface of soil nailing supports is always controversial. According to the Chinese specification, there are no forces acting on soil nailing surface, so the jet concrete surface is designed in terms of certain structure. In fact, the earth pressure on soil nailing has great effect on deformation of the foundation excavations and stress distribution of the wall, especially in deep foundation excavations in soft soil ground. Based on the concept of effective sliding force, and considering with the incremental method, the sliding wedge balance method is improved. Through this complex algorithm, the calculated results indicate that there are forces acting on soil nailing surface, and they are compared with the measured ones. It is shown that the proposed method is practical.