基于光伏桩基试桩结果的m值及桩顶位移研究

Research on value of m and displacement of pile top based on pile test of photovoltaic pile

根据某光伏项目的试桩结果,推算出地基土水平抗力系数的比例系数m值(简称m值)随水平荷载、桩顶位移的变化关系.采用2种方法求解地面处桩身水平位移为10 mm对应的地基土m值,即根据试桩结果推算的方法及根据《建筑桩基技术规范》(JGJ 94-2008)直接计算法.考虑2种不利因素(水平荷载为长期或经常出现的荷载,将m值乘以0.4的折减系数;鱼塘底部表层土受水流冲刷等作用,扣除鱼塘底部表面0.5 m厚的土)求解桩顶水平位移,验算其是否满足《光伏发电站设计规范》(GB 50797-2012)的要求.

This article is based on the result of test of the pile in a photovoltaic project,and calculates the changing relationship among ratio coefficient of the horizontal resistance coefficient of the foundation soil(the value of m for short)and the horizontal load,the displacement of the top of the pile.Using two methods,this article figures out the value of m when the horizontal displacement of pile bod at the ground level equals 10 mm,that is calculating according to the result of the test of the pile and computing directly by taking advantage of Technical code for building pile foundations(JGJ 94-2008).Considering two adverse factors(Because the horizontal load occurs during a long period frequently,the value of m should be multiplied a reduction coefficient 0.4;considering that the soil on the bottom of the fish pond will be flushed by the water,the thickness of the soil on the bottom of fish pond will be deducted by 0.5 m),this article calculates the displacement of the top of the pile,in order to verify whether the displacement is satisfying the requirement of Code for design of photovoltaic power station(GB 50797-2012).