隧道建设
隧道建設
수도건설
TUNNEL CONSTRUCTION
2015年
4期
359-363
,共5页
隧道(洞)%软弱围岩%地应力%变形控制%特殊支护
隧道(洞)%軟弱圍巖%地應力%變形控製%特殊支護
수도(동)%연약위암%지응력%변형공제%특수지호
tunnel%soft surrounding rock%ground stress%deformation control%special support
隧道开挖后受地应力影响极易发生变形,严重的将导致坍方等安全事故,若侵入结构还需要二次扩挖处理。为保障软弱围岩隧道的施工安全,避免二次扩挖,结合国内外隧道的典型案例和经验,从分析围岩的强度应力比出发,针对不同的软岩类型,对预留变形量、预加固措施、弱爆破的基本原则,综合信息方法、支护措施、施工要点等内容进行归纳研究。研究表明:1)预留变形量选择要充分考虑隧道的最大地应力和不同软岩物理特性的影响;2)上台阶采取有效预加固措施后,可以实施大断面开挖;3)不同地应力环境,必须根据信息成果,针对变形特征优化设计支护参数后,变形完全能够有效控制。
隧道開挖後受地應力影響極易髮生變形,嚴重的將導緻坍方等安全事故,若侵入結構還需要二次擴挖處理。為保障軟弱圍巖隧道的施工安全,避免二次擴挖,結閤國內外隧道的典型案例和經驗,從分析圍巖的彊度應力比齣髮,針對不同的軟巖類型,對預留變形量、預加固措施、弱爆破的基本原則,綜閤信息方法、支護措施、施工要點等內容進行歸納研究。研究錶明:1)預留變形量選擇要充分攷慮隧道的最大地應力和不同軟巖物理特性的影響;2)上檯階採取有效預加固措施後,可以實施大斷麵開挖;3)不同地應力環境,必鬚根據信息成果,針對變形特徵優化設計支護參數後,變形完全能夠有效控製。
수도개알후수지응력영향겁역발생변형,엄중적장도치담방등안전사고,약침입결구환수요이차확알처리。위보장연약위암수도적시공안전,피면이차확알,결합국내외수도적전형안례화경험,종분석위암적강도응력비출발,침대불동적연암류형,대예류변형량、예가고조시、약폭파적기본원칙,종합신식방법、지호조시、시공요점등내용진행귀납연구。연구표명:1)예류변형량선택요충분고필수도적최대지응력화불동연암물리특성적영향;2)상태계채취유효예가고조시후,가이실시대단면개알;3)불동지응력배경,필수근거신식성과,침대변형특정우화설계지호삼수후,변형완전능구유효공제。
Due to the effect of ground stress,problems such as deformation,collapse and accident may occur after tunnel excavation,and secondary enlarging excavation may be needed in extreme cases.In the paper,the deformation allowance,advance reinforcement,weak blasting,comprehensive information method,support measures and key construction points for large cross-section tunnels in soft rocks are summarized and studied on basis of typical work cases,so as to guarantee the construction safety of soft rock tunnels and to avoid secondary enlarging excavation.The study shows that:1 )In the determination of the deformation allowance,the maximum ground stress and the physical properties of different soft rocks should be taken into full consideration.2)Large cross-section excavation can be carried out after effective advance reinforcement of the top heading.3)The deformation can be brought under effective control by optimizing the supporting parameters on basic of ground stress and deformation properties.