摘要
针对采用浅埋暗挖法修建的河底公路隧道,通过数值模拟、经验公式与现场实测,研究不同时期的衬砌受力性状。结果表明,在不同河水位下完成双洞的开挖与初衬,河水位越高,初衬拱顶的最大沉降也越大,但先行洞初衬拱顶最大沉降的增加幅度要大于后行洞初衬拱顶最大沉降的增加幅度;可采用折减系数法计算施作二衬前的初衬背后水压力,提出的折减系数的经验取值方法可供类似工程参考;在隧道长期运营后,相比接触密实的状态,仰拱衬砌与围岩之间接触松散使二衬的最大拉应力与最大压应力均增加;提出了隧道上方河水位的经验计算方法,可为研究衬砌的长期受力性状提供参考。
Regarding the highway tunnel crossing the river by shallow mining method, the lining mechanics characters of different times are studied by numerical modeling, empirical formula and field monitoring. The results show that： for the working conditions that two caves are exeavated and supported preliminarily with different river water levels, the crown settlement of the initial lining becomes larger along with the river water level increases, but the increase range of the maximum crown settlement of the initial lining of the former cave is larger than that of the latter cave; the water pressure on the back of the initial lining before constructing the secondary lining might be calculated by the reduction factor method, the empirical method of choosing the reduction factor is put forward and might be referred by the similar projects; after the long-term running of the tunnel, when the contact between the lining and surrounding rock of the inverted arch become loose, the maximum tension stress and the maximum crushing stress of the secondary lining both increased; the empirical method of calculating the river water level above the tunnel is put forward and might provide reference for researching the long-term mechanics character of the lining.
出处
《公路》
北大核心
2017年第2期224-229,共6页
Highway
基金
国家自然科学基金项目
项目编号51408216
湖南省自然科学基金资助项目
项目编号2015JJ6038
关键词
河底隧道
浅埋暗挖法
衬砌
受力性状
河水位
研究
tunnel crossing river
shallow burried method
lining
mechanics character
water level of river
study
