RESEARCH ON FAILURE MODE OF ROAD EMBANKMENT IN WENCHUAN GREAT EARTHQUAKE AND DEFORMATION CONTROL OF GEOGRID REINFORCEMENT
WANG Jian1，YAO Lingkan1，CHEN Qiang2
(1. School of Civil Engineering，Southwest Jiaotong University，Chengdu，Sichuan 610031，China；2. Highway Planning Survey and Research Institute，Sichuan Provincial Communication Department，Chengdu，Sichuan 610041，China)
Abstract：To study the seismic design of subgrade engineering，subgrade seismic damage of Wenchuan Ms8.0 earthquake was investigated. It was found that most of the un-reinforced embankment suffered from shallow collapse of slope，of which a few were damaged by the sliding of embankment body，but neither of the embankment slid along the embankment-foundation interface. the damage level of geogrid-reinforced embankment was much slighter than that of un-reinforced embankment. Based on the investigation，the geogrid layout scheme was proposed to control the lateral deformation of embankment with long geogrid laid on the top of the embankment，and short geogrid laid on the upper part of the embankment. To validate this layout scheme，the un-reinforced and reinforced embankment were studied comparatively with large-scale shaking table model tests. Results showed that fissure spreading downward was restrained by long geogrid on the top of the embankment，thus deep slide prevented. Lateral deformation and shallow slide of the slope were restrained by short geogrid on the upper part of the embankment. By comparative analysis of acceleration and dynamic earth pressure between those two types of model test，it was found that when the road embankment was reinforced，natural frequency would increase by 12%，magnification factor of acceleration at 0.7 times the height of embankment would decrease by 27% under medium earthquake，decrease by 41% under large earthquake，and dynamic earth pressure would decrease largely also.
王建，姚令侃，陈强. 汶川地震路堤成灾模式及土工格栅加筋变形 控制研究[J]. 岩石力学与工程学报, 2010, 29(S1): 3387-3394.
WANG Jian1，YAO Lingkan1，CHEN Qiang2. RESEARCH ON FAILURE MODE OF ROAD EMBANKMENT IN WENCHUAN GREAT EARTHQUAKE AND DEFORMATION CONTROL OF GEOGRID REINFORCEMENT. , 2010, 29(S1): 3387-3394.
