花岗岩残积土地区边坡锚固中锚杆长度及间距的数值优化研究

Numerical optimization of anchor bolt length and spacing for slope reinforcement in granite residual soil area

以广州金山湖第19#地块一个四级人工高边坡为例,采用数值方法计算探讨了锚杆(索)长度及布设间距的优化取值问题。文中以边坡坡级、锚杆间距和锚杆长度为变量参数,获得225种支护组合形式,运用有限差分法计算并获得了225种边坡加固方案的稳定系数,经综合对比分析,得到各个坡级最优的锚杆长度及锚杆间距方案。优化后方案在保证安全的前提下,第二、三、四级边坡采用的锚杆(索)长度较原方案减少了3 m、锚杆布设间距较原方案增加了1 m。

Taking a fourth-grade artificial high slope at block 19 of Guangzhou Jinshan Lake as an example,the optimal values of the bolt(cable)parameters are calculated and discussed.The slope grade,anchor bolt spacing and length are taken as variables to obtain 225 types of support combinations.The finite difference method is used to calculate the safety factors for the 225 types of programs.Through comparison and analysis,the optimal anchor length and anchor spacing of each slope grade are finally obtained.The lengths of the bolt(cable)of the second,third,and fourth grade slopes are reduced by 3 m from the original scheme,while the spacing of the anchor is increased by 1 m in the optimal plan.