国家会议中心二期展览区大跨度转换桁架卸载技术

LARGE-SPAN TRANSFER TRUSS UNLOADING TECHNIQUE IN CHINA NATIONAL CONFERENCE CENTER PHASE Ⅱ

国家会议中心二期展览区转换桁架是目前国内规模最大的转换桁架体系,也是国内首次带桁架层混凝土和上部结构同时卸载的转换桁架结构。卸载施工中,针对转换桁架卸载重量重、面积大、点位多等特点,采用砂箱排砂的方式进行分区分级卸载。经施工模拟、施工监测和对比分析,卸载过程中结构的位移、应力等理论值与实测值吻合良好,证明该卸载方案切实可行。

The transfer truss project in the exhibition area of China National Conference Center phase Ⅱ is the largest transfer truss system in China and it is also the first transfer truss structure that truss concrete and upper structure were unloaded simultaneously.During the unloading construction,considering the characteristics of the transfer truss,such as big weight,big volume and multiple construction points,etc.,sand box discharge method was used for divided and segmented unloading.After construction simulation,construction supervision and comparative analysis,the structural displacement and stress condition during unloading complied with the measured values.It proved that this unloading method is feasible.