锚杆支护边坡在交通振动下的设计主要采用拟静力的方法,无法考虑锚杆和边坡在交通振动下的影响。通过分析交通振动,借助有限差分软件FLAC3D,对锚固公路边坡在交通振动作用下进行动力响应分析。通过对某处半山腰的盘山公路路面施加竖直向下的交通振动,研究锚杆支护公路边坡响应位移、锚杆响应轴力、坡体内响应加速度的变化。研究结果表明:在交通荷载振动下,未支护边坡随着振幅的增加,坡体位移量增加,增加范围在10-2 mm以内,振动影响整个坡面范围,锚杆支护后的边坡位移增加范围在10-3 mm以内,振动影响在距路面竖直距离8m以内;锚杆轴力最大值出现在距路面较近的位置,在距路面0~8m内,响应锚杆轴力较大,超过此范围锚杆轴力在100N以内变化;公路以下坡面各层锚杆轴力最大值出现在埋深6~7m范围内,公路以上坡面出现在埋深2~3m处;随着埋深的增加,坡体内响应加速度迅速衰减,且响应垂直加速度的衰减幅度要略大于水平加速度的衰减幅度。
Currently,the design of bolting slope in traffic vibration is mainly base on pseudo-static method.This method can not consider the effect of traffic vibration on anchor and slope.After analyzing the traffic vibration,this paper did research on the dynamic response of anchoring slope under traffic vibration by means of the FLAC3 Dsoft.Through loading vertical downward traffic vibration on the surface of an anchoring highway slope,this paper studied the dynamic response displacement of soil,the response axial force of bolts,and the response acceleration of soil.The research show that under the traffic vibration,the displacement of slope without bolts will increase with the increase of vibration amplitude,and its increment is in 10-2 mm.The vibration influences the whole face of slope.After anchoring the slope,its increment is in 10-3 mm and the vibration influence sphere is within 8 m high from the road vertically.The max axial force ofbolts appears around the road,in the distance of 0to 8mfrom the road,when the response axial force is larger,and the axial force beyond the distance will vary in the 100 N.Under the road,the max bolts axial force is in the 6-7mdepth.Above the road,the max bolts axial force is in the2-3mdepth.With the increase of burial depth,the soil vibration in the slope reduces rapidly.And the response vertical acceleration reduces a little faster than the response horizontal acceleration.