软土地基上高速公路单侧拓宽路堤变形规律分析与监测

Analysis and Monitoring of Deformation for Single Side Widened Expressway Embankment on Soft Soil Foundation

软土地基上高速公路拓宽时,新老路基结合部会出现差异沉降、路面裂缝等病害。基于D-P模型,采用有限元法分析新路堤作为附拓荷载对老路堤与地基变形的影响,并通过有限元数值模拟计算结果与现场监测数据资料对比。分析表明,拓宽路堤的填筑将会引起老路不同位置的过大附加差异沉降,老路堤靠近中心线出现略微的向上和向内的移动;老路肩有向外的较大的水平位移指向道路的外侧;新路堤靠近坡脚处出现较大的水平位移指向道路的内侧,最大沉降的位置在拓宽后路基表面的中心处,并逐渐向外移动,呈现出一定的规律性。

When widening an expressway on soft soil subgrade, differential settlement and pavementcracking along the joint between the old and new road base often appear. The effects on old embankmentcaused by new road base with additional load are analyzed with finite element method based on D-P model,and comparison are made between field monitoring data and finite element numerical simulation. Theresults indicate that the construction of new embankment induces unacceptable differential settlementsbetween the center and the shoulder of old embankment, and embankment moves upper and lower slightlynear the central line; old road shoulder has larger horizontal displacement outward to lateral side of theroad; new embankment near the slope angle has larger horizontal displacement inward to medial side of theroad, the position of maximum settlement appears in the center of embankment surface after widening,moves outside gradually, and shows certain regularity.