黄土地区浅埋暗挖地铁隧道施工地层变形规律

发布时间：2018-09-19 07:44

【摘要】：为了解黄土地区浅埋暗挖地铁隧道地层变形规律,利用自主研发的多点位移计对西安地铁2号线实体工程进行地层变形量测,该多点位移计具有精度高、量程大易于生产、便于运输、锚头结构简单等特点,适用于隧道浅埋段围岩内部位移的量测。测量结果表明:地层变形从大到小顺序为拱顶附近、8~10 m之间地层地表、2~6 m之间地层;各测点的沉降呈二阶台阶状,施工降水为第一个下降台阶,掌子面开挖为第二个下降台阶;地层横断面变形呈漏斗形,隧道中心轴附近地层沉降值最大,越向两边地层沉降值越小。地层各点沉降经历4个阶段:降水沉降阶段,占总沉降值的45%左右;微小沉降阶段,占总沉降值的不足10%;沉降剧增阶段,占总沉降值40%~50%;沉降基本稳定阶段。
[Abstract]:In order to understand the deformation law of shallow buried underground subway tunnel in loess area, the multi-point displacement meter developed by ourselves is used to measure the ground deformation of Xi'an Metro Line 2 solid project. The multi-point displacement meter has high precision and is easy to produce. It is convenient for transportation and simple in structure of anchor head. It is suitable for measuring the internal displacement of surrounding rock in shallow section of tunnel. The measurement results show that the order of formation deformation from large to small is between 2m and 6m of ground surface near the arch roof, the settlement of each measuring point is second-order step, the construction precipitation is the first descending step, and the excavation of palm surface is the second descending step. The deformation of cross section is funnel-shaped, the settlement value of stratum near the center axis of tunnel is the largest, and the settlement value of the strata is smaller when it moves to both sides of the tunnel. There are four stages of formation subsidence: precipitation subsidence stage, accounting for about 45% of the total settlement value; small settlement stage, less than 10 percent of the total settlement value; precipitation-increasing stage, accounting for 40% of total settlement value; and settling stable stage.
【作者单位】：西安市地下铁道有限责任公司;长安大学桥梁与隧道陕西省重点实验室;
【基金】：国家自然科学基金项目(51008029) 中央高校基本科研业务费专项资金(CHD2012ZD 019)
【分类号】：U456.3

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