摘要
研究目的:在城市铁路建设中,受地方规划、城市建设因素的控制,越来越多地出现厚填土重荷载铁路明洞,尤其在山区城市,明洞还可能修建在高路基填方之上。这类明洞较一般明洞受力更为复杂,设计需考虑的因素也更多,以重庆至利川铁路丰都造地明洞为工程原型,分别从荷载组合、明洞结构选型、衬砌受力分析、内外衬关键工序、基础处理形式、回填工程稳定性及回填施工工艺等关键设计技术进行研究论证。研究结论:(1)明洞结构采用双层衬砌的设计方法,外衬承担填土荷载,内衬作为后期荷载的补强结构;(2)有限元结构分析表明,内衬需在外衬、Ⅰ期填土完成后施作,明洞、混凝土基础及地基的受力安全、结构稳定性和回填工程的局部及整体稳定性可满足要求;(3)为防止回填土对明洞的偏压推力,明洞底板应设置竖向抗剪桩;(4)回填施工工艺是保证坝与明洞稳定的关键,混凝土坝施工应控制浇筑温度,降低水化热;(5)该研究成果对明挖法施工的城市铁路、公路、地铁隧道,特别涉及厚填土、重荷载、深基础的明洞结构具有重要的参考价值和借鉴意义。
Research purposes： In the construction of the urban railway, more and more thick filling and heavy load railway open cut tunnels have been appearing in the control of factors of urban layout and construction , especially in the mountainous city, open cut tunnels may also be built above the high filling roadbed. The kind of railway open cut tunnel is more complex than common open cut tunnel, the more factors should be considered in design, around the open -cut tunnel for Fengdu land reclamation on the railway line from Chongqing to Lichuan for the engineering prototype, the critical design features including load combination, open -cut tunnel selection, lining stress analysis, internal and external lining critical process, foundation disposing formation, the whole stability, on, are analyzed respectively. filling construction technology and so Research conclusions：This paper proposes the double lining design method of outer lining bearing filling load and inner lining reinforcing structure and bearing later load. By means of finite element structure analysis, the key process is determined which inner lining must be exerted after the completion of outer liner and I - period filling, these design measures can ensure the stress safety and structure stability of open cut tunnel, concrete dam and foundation, and the whole and part stability of filling engineering. The method of shear pile on the bottom of open cut tunnel will prevent filling from pushing tunnel is proposed. Filling construction technology is key to ensuring the stability of open cut tunnel and dam, and the construction of concrete dam should control casting temperature and decline heat of hydration. Research achievements have important reference value and significance on the open excavation construction of railway, highway, subway tunnels, especially involving the open cut structure of thick filling, heavy load and deep foundation.
出处
《铁道工程学报》
EI
北大核心
2013年第12期51-56,共6页
Journal of Railway Engineering Society
关键词
超厚填土
城市铁路明洞
明洞设计
内、外衬砌
回填造地
extra - high filling
urban railway open cut tunnel
design of open cut tunnel
inner - outer lining
backfilling and land reclamation
