It is a common type of tunnel under-cross the roadbed slope with weak inter-layer. Rainfall infiltration will cause soil softening, matric suction and strength reduction, which seriously threaten the safety of slope and tunnel. This paper presents a case where a tunnel underlying the roadbed slope with weak inter-layer in Guiyang 1# line, China. The seepage calculation model in MIDAS GTS/NX software, considering hydraulic permeability coefficient characteristic curve and soil-water characteristic curve, was used to analyze the stress and deformation of the roadbed slope and tunnel. The results reveal that rainfall infiltration has great influence on the deformation of roadbed slope with weak inter-layer and the force of internal tunnel. Slope displacement increases rapidly in the early stage and decreases in the late stage, but the absolute value of displacement increases continuously and the slope safety factor decreases gradually, which makes the slope in a dangerous state. The force of tunnel lining increases in the early stage and decreases with the recovery of soil strength after rainfall. The control effects of anchor cable and anti-slide pile reinforcement on slope sliding and tunnel stress were studied. And the anchor cable reinforcement measure is more effective on reducing slope slip and tunnel lining structure internal force.

它是跨层薄弱的穿越路基边坡的一种常见隧道。降雨入渗将导致土壤软化，基质吸力和强度降低，从而严重威胁斜坡和隧道的安全。本文以贵阳1＃线弱层间路基边坡下的隧道为例。利用MIDAS GTS / NX软件中的渗流计算模型，考虑了渗透系数系数曲线和土壤-水特征曲线，对路基边坡和隧道的应力和变形进行了分析。结果表明，降雨入渗对夹层较弱的路基边坡变形和内部隧道的力影响很大。坡度位移在早期阶段迅速增加，而在后期阶段减少，但是位移的绝对值不断增加，边坡安全系数逐渐减小，使边坡处于危险状态。隧道衬砌的力在早期增加，并随着降雨后土壤强度的恢复而减小。研究了锚索和抗滑桩加固对边坡滑移和隧道应力的控制效果。锚索加固措施在减少边坡滑移和隧道衬砌结构内力方面更有效。研究了锚索和抗滑桩加固对边坡滑移和隧道应力的控制效果。锚索加固措施在减少边坡滑移和隧道衬砌结构内力方面更有效。研究了锚索和抗滑桩加固对边坡滑移和隧道应力的控制效果。锚索加固措施在减少边坡滑移和隧道衬砌结构内力方面更有效。