【摘要】 为揭示湿陷性黄土地区过湿拓宽路基变形破坏机理及强夯法处治效应,研制了离心场土工构造物变形测试系统,升级传感器电测手段,以浸水入渗条件下高速公路拓宽工程为研究载体,建立与实际应力相符的离心试验模型,通过试验得出了浸水增湿后拓宽路基的沉降变形特征和拓宽地基强夯处治效果。结果表明:拓宽路基坡脚处高含水量对拓宽黄土路基稳定性有显著影响,新路基坡脚水分聚集或地基内部水位上升导致黄土地基发生湿陷的条件成熟,在上部拓宽路基荷载的作用下,整个地基会发生整体或局部湿陷,进而引发整个拓宽新老路基脱节滑移;强夯法能很好地改善黄土地基的湿陷性,保证拓宽路基的整体稳定性。更多还原

【Abstract】 In order to study the failure mechanism and dynamic compaction method treatment effect of widening collapsible loess roadbed,authors developed centrifugal deformation field test system of geotechnical structures and upgraded electrical measuring instruments of sensors.Regarded widening engineering of expressway under water infiltration as research object,centrifugal test model which was in line with the actual stress was set up.Settlement deformation characteristics and dynamic compaction method treatment effect of widening roadbed were tested after immersion and humidity damage.Results show that the influence of high water content at widening roadbed foot on the stability of loess roadbed is remarkable.Condition of loess roadbed collapse caused by moisture assembling of new road foot and water line elevation of internal road is mature.Whole roadbed will be collapsible under upper widening roadbed load which causes slippage of new and old widening roadbed.Dynamic compaction method can effectively improve the dynamic compaction of collapsible loess foundation and can ensure the overall stability of the roadbed widening.更多还原