隧道建设
隧道建設
수도건설
TUNNEL CONSTRUCTION
2012年
3期
302-308
,共7页
土压平衡盾构%螺旋输送机%排土%保压%渣土改良
土壓平衡盾構%螺鏇輸送機%排土%保壓%渣土改良
토압평형순구%라선수송궤%배토%보압%사토개량
EPB shield%screw conveyor%earth conveying%pressure maintaining%ground conditioning
螺旋输送机的排土和保压作用的发挥对土压平衡盾构的施工安全与效率有重要影响,对其作用机制及影响其作用发挥的因素进行系统的理论分析,并参考工程实测数据,得出以下结论:1)盾构施工中的土压平衡包括土仓内外与螺旋输送机内的压力平衡和进、出土量的平衡,其通过螺旋输送机排土量的控制来实现;2)渣土进入螺旋输送机后,依靠自身重力及与螺杆、叶片和筒壁界面间的摩擦作用来抵抗土仓内的水土压力,保持出渣过程的稳定性;3)渣土性质对螺旋输送机的排土和保压效果有较大影响,主要通过向刀盘前方和土仓内添加改良材料的方法对渣土状态进行调整;4)从螺旋输送机结构分析,可通过减小螺距、采用间断式螺杆或双螺旋输送机3个方面进行改造,以增加保压效果。
螺鏇輸送機的排土和保壓作用的髮揮對土壓平衡盾構的施工安全與效率有重要影響,對其作用機製及影響其作用髮揮的因素進行繫統的理論分析,併參攷工程實測數據,得齣以下結論:1)盾構施工中的土壓平衡包括土倉內外與螺鏇輸送機內的壓力平衡和進、齣土量的平衡,其通過螺鏇輸送機排土量的控製來實現;2)渣土進入螺鏇輸送機後,依靠自身重力及與螺桿、葉片和筒壁界麵間的摩抆作用來牴抗土倉內的水土壓力,保持齣渣過程的穩定性;3)渣土性質對螺鏇輸送機的排土和保壓效果有較大影響,主要通過嚮刀盤前方和土倉內添加改良材料的方法對渣土狀態進行調整;4)從螺鏇輸送機結構分析,可通過減小螺距、採用間斷式螺桿或雙螺鏇輸送機3箇方麵進行改造,以增加保壓效果。
라선수송궤적배토화보압작용적발휘대토압평형순구적시공안전여효솔유중요영향,대기작용궤제급영향기작용발휘적인소진행계통적이론분석,병삼고공정실측수거,득출이하결론:1)순구시공중적토압평형포괄토창내외여라선수송궤내적압력평형화진、출토량적평형,기통과라선수송궤배토량적공제래실현;2)사토진입라선수송궤후,의고자신중력급여라간、협편화통벽계면간적마찰작용래저항토창내적수토압력,보지출사과정적은정성;3)사토성질대라선수송궤적배토화보압효과유교대영향,주요통과향도반전방화토창내첨가개량재료적방법대사토상태진행조정;4)종라선수송궤결구분석,가통과감소라거、채용간단식라간혹쌍라선수송궤3개방면진행개조,이증가보압효과。
The earth conveying and pressure maintaining of screw conveyors play an important role in the safe and effi- cient boring of EPB shields. The working principles and influencing factors of the earth conveying and pressure maintai- ning of screw conveyors are systematically analyzed. Conclusions drawn are as follows : 1 ) The earth pressure balance in the boring of EPB shields includes the pressure balance between inside chamber and outside chamber, the pressure bal- ance inside the screw conveyor, and the earth input/output volume balance, which can be realized by controlling the volume of earth conveyed. 2) When the earth enters the screw conveyors, the water/soil pressure in the chamber is re- sisted by the gravity of the earth and the friction with the screw rod, lamina and the inner side of the conveyor, so as to keep stable earth conveying. 3 ) The earth behavior, which has great influence on the earth conveying and pressure maintaining of screw conveyors, can be improved by injecting ground conditioning agents into areas ahead of the cutter heads and into the chamber. 4) Regarding the structure of the screw conveyor, the pressure maintaining effect can be improved by means of reducing the pitch, adopting discontinuous screw and double screw conveyors.