【摘要】 以西安某段地裂缝为原型,通过几何比1∶25的模型试验,研究了地裂缝活动对分段式衬砌结构受力变形的影响效应。由试验结果得出:由于分段式衬砌每一段均可以满足一定量的独立变形,且对附近的衬砌段影响较小,所以较能适应地裂缝环境。当地裂缝活动时,衬砌顶部10cm处土压力在上盘靠近裂缝两段及下盘靠近裂缝一段均减小;衬砌底部5cm处土压力在上盘靠近裂缝段减小,在下盘靠近裂缝段增大;其余段影响较小。上盘靠近裂缝两段衬砌顶部和底部均受纵向压力;下盘靠近裂缝段衬砌顶部受拉,底部受压;其余段影响较小。上盘靠近裂缝段衬砌两侧面受压,下盘影响较小。衬砌的破坏模式主要为侧壁受环向挤压破坏,多发生在上盘尤其是靠近裂缝的结构段;土体内次生裂缝不发育,仅出现在上盘顶部预设裂缝附近以及下盘土体内部,土体受张拉剪切作用,形成张剪裂缝。更多还原

【Abstract】 By use of a 1 ∶2 5 model to simulate one section of the ground fissure in Xi’an, the effect of ground fissure activities on segmental lining is studied. The results indicate that each segment of lining can satisfy the quantitative unattached deformation and there is very small effect between each segment lining, so it can adapt to the ground fissure surroundings. When a fissure moves, the earth pressure at the lining top at the depth of 10 cm of two segments in the hanging wall and one segment in the footwall near the fissure decreases. The earth pressure at the lining bottom at the depth of 5 cm of one segment in the hanging wall near the fissure decreases, but that in the footwall increases. The top and bottom of two segment linings near the fissure in the hanging wall are longitudinally pressed. The top of one segmental lining in the footwall is pulled, but its bottom is pressed. Both sides of the lining near the fissure in the hanging wall are pressed, and the effect is smaller in the footwall. The main failure mode for the linings is that sidewall suffers hoop extrusion, which often occurs in the hanging wall, especially near the fissure. The secondary fissures in the soil do not develop, and they only appear on the top of the hanging wall near the fissure and inside the soil of the footwall. The soil is pulled and sheared to form the fissure.更多还原