CAJ | 학술논문

盾构在复合砂性土层中掘进时容易发生开挖面失稳事故，因此掘进过程中开挖面保持合理支护压力尤为重要。考虑到砂性土的摩擦特性，采用上限分析原理并建立适合复合砂性土层的三维破坏机动场模型对开挖面失稳进行分析，最终得到该类地质条件下开挖面最小支护压力计算公式。给定穿越土层参数条件下，考虑覆土层为均一土层和双层土2种工况，分析研究盾构直径，埋深比，覆土层黏聚力，覆土层内摩擦角，地表荷载和覆土层相对厚度比等因素变化对支护压力的影响。该公式为复合砂性土层下开挖面支护压力设置提供了较为精确估算方法，为类似实际工程提供重要理论依据。
순구재복합사성토층중굴진시용역발생개알면실은사고，인차굴진과정중개알면보지합리지호압력우위중요。고필도사성토적마찰특성，채용상한분석원리병건립괄합복합사성토층적삼유파배궤동장모형대개알면실은진행분석，최종득도해류지질조건하개알면최소지호압력계산공식。급정천월토층삼수조건하，고필복토층위균일토층화쌍층토2충공황，분석연구순구직경，매심비，복토층점취력，복토층내마찰각，지표하재화복토층상대후도비등인소변화대지호압력적영향。해공식위복합사성토층하개알면지호압력설치제공료교위정학고산방법，위유사실제공정제공중요이론의거。
The tunnel working face easily collapses when tunneling is conducted in the composited sandy soil, thus it is important to maintain the proper support pressure for the working face stability. According to the frictional characteristics of sandy soil,the upper bound analysis is applied to analyze the working face stability by using the improved 3D kenimatically admissible mechanisms, and the formula of the minimum support pressure for the working face stability is obtained. As the crossed soil is defined,the influence of the tunnel diameter,the depth ratio,the ground surface surcharge,the cohesion and the friction angle of the cover layers and the relative thickness ratio of cover layers on the support pressure is studied. This study presents an accurate estimation of support pressure for the tunnel working face stability in the composited sandy soils as well as an important theoretical reference to the similar practice projects.