基于FLAC^(3D)原理模拟斜井支护效果研究

Research on the Supporting Effect of Inclined Shaft Simulation Based on FLAC^(3D) Principle

【目的】斜井介于平港和竖井之间,结构受力具有一定的复杂性,因此研究斜井硐室开挖和支护的有效性和可行性尤为重要,有必要对斜井支护效果展开研究。【方法】采用FLAC^(3D)对斜井围岩变形及支护技术方案的应力场、位移场和塑性区的分布变化情况进行数值模拟分析。【结果】在斜井开挖过程中,未支护工况下城门型斜井拱腰、拱顶、拱脚及底板等三处是开挖围岩最不稳定区域。支护后的围岩应力场、位移场和塑性区的分布减少了较多,其中,拱顶下沉位移量从57 mm降至5.3 mm;拱腰处水平位移量从26.7 mm降至15.7 mm;底板水平位移量从11.3 mm降至7.14 mm。【结论】在支护工况下的围岩应力场、位移场和塑性区的分布得到了较好改善,对斜井围岩的位移变形、塑性区范围起到了显著的控制作用。

[Purposes]The inclined shaft is between the flat port and the shaft,and the structural stress has certain complexity.Therefore,it is particularly important to study the effectiveness and feasibility of the excavation and support of the inclined shaft chamber,and it is necessary to study the supporting effect of the inclined shaft.[Methods]FLAC^(3D) was used to conduct numerical simulation analysis of the distribution changes of stress field,displacement field and plastic zone of the surrounding rock deformation and support technical scheme of inclined shaft.[Findings]In the process of excavation of inclined shafts,the arch,vault,arch foot and floor of the gate-type inclined shaft were the three most unstable areas of excavation surrounding rock under unsupported conditions.The distribution of stress field,displacement field and plastic zone of surrounding rock after support is reduced,and the displacement of vault subsidence is reduced from 57 mm to 5.3 mm.The horizontal displacement at the arch decreases from 26.7 mm to 15.7 mm.The horizontal displacement of the floor decreases from 11.3 mm to 7.14 mm.[Conclusions]The distribution of stress field,displacement field and plastic zone of surrounding rock under supporting conditions is well improved,which plays a significant role in controlling the displace ment deformation and plastic zone range of surrounding rock of inclined shaft.