摘要
利用有限差分法FLAC3D软件建立节理岩质边坡桩基加固的数值模型,通过强度折减法计算边坡安全系数,并分析边坡节理面倾角、桩长、桩位置对节理岩质边坡稳定性及桩身内力与位移的影响。研究结果表明:桩总长L1存在某一临界桩长L0,当L1>L0时,增加桩总长对桩加固效果影响不大;节理上部桩长L2是影响桩加固岩质边坡效果的决定性长度参数;桩位置逐渐远离坡面时,加固效果急剧降低;桩身剪力和弯矩均呈周期性波形分布,最大剪力绝对值出现桩与节理面的相交点处,最大弯矩出现在剪力约等于0 kN处;当节理面倾角大于岩石摩擦角时,桩顶水平位移随着桩位置逐渐远离坡面而急剧增大。为了提高桩基加固效果,实际工程中桩总长应小于临界桩长,且尽可能布置桩在坡面附近。
Finite difference software FLAC3 D was used to establish numerical model of the jointed rock slope reinforced by pile foundation and calculate the slope of safety factor by the shear strength reduction method. Influencing factors of the slope stability and internal force and displacement of the pile were analyzed including inclination angle of the joint surface and total length and location of the pile. The results show that there exists a critical length L0 for the total length L1 of the pile and the increase of L1 has little effect on the slope stability when L1〉L0. The pile length above the joint L2 is a dominant length parameter for influencing the jointed rock slope stability. Gradual moving of the pile away from the slope surface can result in great decrease of the slope stability. Both shear force and bending moment of the pile are distributed in periodic waveform, where maximum absolute value of the shear force appears at intersection point of the pile and the joint and maximum bending moment appears at the place of shear force of 0 kN. When the inclination angle of the joint surface is larger than the friction angle of rock, horizontal displacement of the pile top increase rapidly as the pile location is gradually away from the slope surface. In order to improve reinforcement effect of the pile foundation, total length of the pile should be smaller than its critical length and the pile location must be as close to the slope surface as possible in practical engineering.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2014年第8期2774-2780,共7页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(11072269)
关键词
岩质边坡
节理
桩基
稳定性
有限差分法
强度折减法
rock slope
joint
pile foundation
slope stability
finite difference method
strength reduction FEM
