公路工程

以四川省某公路的高水压隧道为对象,采用有限元软件ANSYS11.0,对其结构的受力特征和围岩的稳定性进行了研究。结果表明,水压力对隧道所受的轴力、弯矩、剪力影响最大,受水压力的影响,轴力增加69%以上、弯矩增加97%以上、剪力增加203%以上。在水压力作用系数相同时,在衬砌背后排水系统排出的地下水时,衬砌内力、塑性应变、隧道位移最大值要大于从衬砌渗出的数值,但增幅很小。无论是蛋形断面还是圆形断面,隧道轴力、位移矢量、竖向位移的最大值均有一定程度的减小,两种断面的减小幅度非常相近,圆形断面对隧道结构受力与围岩稳定性要比蛋形断面好。水压力分布不均匀的衬砌内力、塑性应变、隧道位移最大值比分布均匀的要大,其中弯矩、塑性应变最大值增加非常明显,分别增加了100%、443%,水压力分布不均匀对隧道结构受力、围岩稳定性影响较大。

This paper takes the high water pressure tunnel of a highway in Sichuan Province as the object,using the finite element software ANSYS11. 0,the stress characteristics of the structure and the stability of the surrounding rock are studied. The results show that the influence of axial force,bending moment and shearing force on the axial force,bending moment and shearing force of water pressure is greatest,and the axial force is increased by more than 69%,and the bending moment is increased by more than 97%,and the shear force is increased by more than 203%. When the water pressure is the same,the internal force,plastic strain and the maximum value of the displacement of the tunnel are larger than that of the lining,but the increase is very small. Whether it is egg shaped section or circular cross section,the maximum value decreases to a certain extent,the axial force of tunnel displacement,vertical displacement,the two section of the decrease is very similar to that of circular cross section of tunnel structure stress and rock stability than a good egg shaped section. The water pressure of the uneven distribution of lining stress,plastic strain,the maximum displacement of the tunnel is bigger than uniform distribution,the maximum bending moment and plastic strain increased obviously,which increased by 100% and 443%,the uneven distribution of water pressure on tunnel structure stress and rock stability greatly.