浅埋暗挖隧道穿越填石区地表沉降控制

厦门城市轨道交通1号线城市广场站—塘边站浅埋暗挖区间采用矿山法施工,由于隧道穿越地质条件复杂的填石区地表沉降难以控制。仅采取喷射混凝土封闭掌子面、注浆加固、加强超前支护措施累计地表沉降接近70 mm;而采取地表高压旋喷桩超前加固,洞内全断面帷幕注浆、双层小导管超前支护等多种措施,能将地表沉降控制在5 mm以内。据此提出了地表高压旋喷桩超前加固、全断面帷幕注浆、双层小导管超前支护、长管棚初期支护和拱脚加固施工方法。经实施效果良好。研究成果能为城市浅埋暗挖隧道穿越填石区提供参考。

Ground Surface Settlement Control of Shallow-buried Underground Excavation Tunnel Crossing Rock-filling Area

Shallow-buried underground excavation interval section between City Square Station and Tangbian Station of Xiamen urban rail transit Line 1 was constructed by mining method.It is diff icult to control the ground surface settlement of the tunnel crossing the rock-f illing area in complex geological conditions.The cumulative ground surface settlement is close to 70 mm only by means of shotcrete sealing tunnel face,grouting reinforcement and strengthening advanced support.The ground surface settlement can be controlled within 5 mm by adopting many measures,such as advanced reinforcement with ground high-pressure jet grouting pile,full-section curtain grouting in tunnel and advance support of double-layer small conduit and so on.Based on these methods,the construction methods of advanced reinforcement with ground high-pressure jet grouting pile,full-section curtain grouting,advance support of double-layer small conduit,primary support of long pipe shed and arch foot reinforcement were put forward and the implementation effect is good,the research result of which can provide references for shallow-buried underground excavation tunnel crossing the rock-f illing area in cities.