组合式支锚体系在软土基坑工程中的应用

Application of the Combined Supporting and Anchoring System for a Deep Excavation in Soft Soils

基坑工程是建筑主体结构的地下部分开挖施工阶段的临时性围护工程,其寿命短暂,地下结构施工完毕后即失去使用价值,因此提高支护结构的经济性成为基础建设行业的迫切需求。因复杂多变的周边环境,强桩强撑仍然是目前中心城区基坑支护的主要设计理念,但其使用意味着支护造价高昂。在存在深厚软土基坑工程中,往往通过增加桩长、桩径、配筋等支护桩强度参数,以满足变形控制以及稳定性计算要求。组合式支锚体系是支撑、锚索在一个支护断面上同时使用的支护体系,在桩撑支护的基础上增加锚索使支护桩的受力和变形得到改善,可在满足支护结构安全要求的情况下,有效降低支护结构的整体造价。

Deep excavation engineering is a temporary supporting structure for the excavation of underground construction.It has the characteristics of the short service life,and the supporting structure will be out of service when the underground construction is completed.Therefore,the improvement of the cost effectiveness of the excavation supporting is becoming an imperative requirement of the entire construction industry.With a high construction cost,the strong soldier pile with a strong stiffness of the supporting structure is a major design trend of the urban deep excavation projects due to the restrictive requirements of the adjacent urban environments.In the deep excavation in thick and soft cohesive soil,the deformation and global stability could be adjusted the solider pile length,diameter and the number of steel reinforcement bars.The combined support and anchor system is a support system in which the support and the ground anchor are used simultaneously on a supporting system.Adding the ground anchor to the soldier pile supporting system can improve the stress and deformation of the support soldier piles,which can effectively reduce the overall construction cost of the support structure while meeting the safety requirements.