大西客运专线小角度穿越地裂缝带的模拟分析

Simulation Analysis of Datong-Xi'an Passenger Dedicated Railway Crossing Ground Fissure Belt with a Small Angle

运用MIDAS/GTS软件对大西客运专线路基小角度穿越地裂缝带进行模拟,研究路基应力场和位移场的变化规律。计算结果表明:交角越大复合地基抵抗沉降变形的能力越强;小交角条件下路基地基钢筋混凝土板上盘受压,下盘受拉,底板纵向应变随上盘沉降的增加而增大,是明显的横"S"形反对称规律;交角为15°,30°,45°时,地裂缝作用下路基底部钢筋混凝土板开裂破坏对应的上盘沉降临界值分别为20,10,5 cm。

The Datong-Xi'an passenger dedicated railway crossing the ground fissure belt with a small angle was simulated by using MIDAS/GTS software and the variation law of subgrade stress field and displacement field was studied T he calculation results show that the ability of composite foundation to resist settlement deformation is strong with the angel increasing,the upper plate of subgrade foundation reinforced concrete base slab is pressed and the bottom plate of that is pulled under the condition of small angle,the longitudinal strain of base slab increases with settlement of upper plate increasing,which shows the obvious horizontal S type antisymmetric law,and the upper plate settlement thresholds for cracking failure of the subgrade bottom reinforced concrete base slab under the action of ground fissure are20cm,10cm and10cm respectively when the subgrade crosses the ground fissure with the angle of15°,30°and45°.