2011年12月下施工技术 第40卷第355期CONSTRUCTIONTECHNOLOGY
土钉支护基坑阳角的冗余度研究
王海旭',程雪松',郑刚² (1,天津大学土木工程系,天津300072;2.滨海土木工程结构与安全教育部重点实验室,天津300072) [摘要]基坑阳角是变形控制的不利位置,在设计中应予以重点加固。
在基坑工程领域引人冗余度设计理论的概 念,对土钉支护基坑的阳角进行腰梁加固,并对其冗余度进行分析。
对比分析了原体系与冗余体系的坑壁水平位 移、土钉轴力等内容;研究了局部土钉失效时,土钉-腰梁支护体系的工作状况。
结果证明对土钉支护基坑的阳角 进行腰梁加固能够有效控制危险位置位移,转移余荷载,增加荷载传递路径,即能够提高支护体系余度。
[关键词]地下工程;基坑;阳角;土钉;冗余度 【中图分类号】TU311.41[文献标识码]A[文章编号]1002-8498(2011)24-0037-06 Study on Redundancy ofFoundation Excavation Convex Location Supported by Soil Nailing Wang Haixu', Cheng Xuesong',Zheng Gang² (1.Departmentof CivilEngineering,TianjinUniversity,Tianjin300072,China; 2.MOE Key Laboratory of Coast Civil Structure Safety,Tianjin300072,China) Abstract;As the convex location of foundation excavation is disadvantageous locations to control its displacement,a special consolidation design is necessary.The redundancy theory on design is introduced for the underground engineering field. The convex location of foundation excavation supported by soil nailing has been consolidated with breast beam and its redundancy has been analyzed. The horizontal displacement of the side-wall, the axial force of soil nailing in original system and redundant system have been respectively analyzed and pared. The work situation of soil nailing with breast beam support system when part of soil nailing failed has been studied. The results prove that consolidating the convex location of excavation supported by soil nailing with breast beam can effectively control the displacement of dangerous location,transfer the redundant load and increase the transferring path. Hence, it can improve the redundancy of support system. Key words:underground; foundation excavation; convex location; soil nailing; redundancy 0引言州塔等[。
然而,在深基坑工程等地下工程中,冗 冗余度[设计是重大、复杂受力结构体系的余度理论的研究在国内外几乎是空白。
原则。
在土木工程中,冗余度可以被认为是抵抗连近年来,国内外发生了不少重大基坑工程事 续倒塌的能力,如果结构体系的某个构件由于自身故,例如,新加坡地铁NicollHighway事故、杭州地铁 强度不足或外部偶然荷载的作用而发生破坏,理想湘湖站事故等,这些发生事故的基坑支护结构大多 的结构应该仍然能够继续承担荷载,而不至于连续存在冗余度不足的问题。
导致基坑支护结构存 倒塌。...