盾构穿过矿山法隧道的管片特性现场试验研究

以深圳市地铁某区间隧道为背景工程，针对矿山法+盾构法的复合施工法中二衬管片受力特性进行现场试验，埋设混凝土应变计、土压力盒和钢筋轴力计等仪器，监测并分析混凝土管片环缝接触面纵向应变、土压力以及钢筋轴力的变化规律.结果表明：监测量随时间的变化可分为2个阶段，整体预压力基本满足要求；混凝土管片环缝接触面纵向应变和土压力沿环向的分布极不均匀，壁后压浆能够改善管片的受力和控制上浮；实测管片钢筋的轴力远小于其设计值，应优化其配筋设计；需对环间螺栓进行多次有序复紧，对管片进行多次壁后补压浆.

Field Test of Segment Characteristics for Shield Advancing in Mined Tunnel

In the construction of a certain tunnel in Shenzhen Metro, a field test of segment characteristics was conducted for the novel shield after the drill and blast composite construction method. The concrete strain gauge, earth pressure cell and reinforced axial dynamometer were installed. The variation laws for the longitudinal strain of girth contact surface for concrete segment, earth pressure and axial force of reinforced instrument were monitored and discussed. The results show that the variation with time of monitoring values can be divided into two stages; the overall pre pressure basically meets the requirement; the longitudinal strain of girth contact surface for concrete segment and earth pressure are very unevenly distributed; grouting can improve and control the force and floating of segment; reinforcement design of segment should be optimized as the measured axial force is much smaller than its design value; a number of orderly tightening ring bolts and grouting behind wall segment are needed. Key words：