综合考虑各影响因素下浅埋室顶板最大安全荷载预测

以新疆乌鲁木齐“世纪花苑”三期工程人防地道为例,运用快速拉格朗日差分分析程序,通过逐渐调整上部荷载大小,使其达到临界状态下的数值模拟方法,系统分析不同影响因素(如洞跨、顶拱高跨比、顶板厚度、荷载范围等)对人防地道顶板最大安全荷载的影响及相关变化规律。结果表明,顶板最大安全荷载与洞跨及荷载范围成反比,而与顶拱高跨比、顶板厚度和荷载偏心率成正比。在此基础上,用数理统计方法得出能综合考虑各影响因素下顶板最大安全荷载的预测方程。

Forecasting Maximum Safety Loading of Roof in Shallow Underground Excavation under Different Conditions

To take the shallow underground excavation of Garden of Century" in Urumchi Xinjiang as an (example), we make use of Fast Lagrange Analysis of Continua (FLAC), gradually adjust upper loading of its roof wall rock and make it attain to critical state by digital-analog method, systematically analyze stability and failure mechanism of shallow underground excavation and maximum safety loading of roof wall rock under different (affecting) factors, for example, cavern span, depth-span ratio of roof, roof (thickness) and load distribution range etc. On the basis of calculation results, we systematically research the variability rule of maximum safety loading of roof under different affecting factors. The results show that the roof maximum safety loading is in inverse (ratio) to cavern span and load distribution range, but direct proportion with depth-span ratio of roof, roof (thickness) and the eccentric distance of loading. The forecasting equation with maximum safety loading of roof (related) with different affecting factors is obtained by mathematical statistics.