隧道冻结过程与邻近建筑物相互影响分析

Analysis of the Effects of the Tunnel Frozen Construction Process on Ajacent Buildings

文章以拱北隧道冻结帷幕的冻结施工过程为依据,建立三维有限元冻结模型,分析了冻结施工与邻近建筑物的相互影响,结果表明:冻结过程中地表变形整体表现为隆起,其隆起量大小由冻结帷幕中心向两边逐渐减小,并在远离中心的两侧表现出微弱的沉降变形,在横断面上呈现出近似抛物线的形状;相邻建筑物的存在,会抑制地表的冻胀变形,其隆起变形仍然呈现出抛物线的形状,但抛物线的对称轴向邻近建筑物一侧有所偏移;冻结过程中建筑物的倾斜率均在规范容许限值的范围内,建筑物的拉、压应变也在混凝土极限拉、压应变范围之内,建筑物不会产生倾覆破坏或者局部梁、板、柱的开裂。

Based on the frozen construction of the frozen soil curtain wall of Gongbei Tunnel,a 3 D FEM frozen model is established to simulate the effects of frozen construction on adjacent buildings.The analysis results show that during the process of frozen construction,the overall surface deformation presents the uplifting behavior,the deformation values decrease gradually from the centre of the frozen soil curtain wall to the two sides,and slight settlement deformation may arise on the two sides far away from the centre,therefore presenting a similar parabola curve at the cross section.The existence of adjacent buildings will restrain the frost deformation,but the uplifting deformation will be in parabola curve shape as well as the top of the parabola will move slightly to the adjacent buildings.During the process of frozen construction,the inclination ratio of buildings is within the specified allowable values,and the tensile strain is also within the concrete ultimate tensile strain,which will not lead to overturning failure and cracking of beams,slabs,and columns.