CAJ | 학술논문

针对地下连续墙成槽施工过程中的槽壁稳定性及其失稳现象,分别从地下连续墙槽壁稳定影响因素、槽壁整体及局部失稳机制、不同施工阶段槽壁土体的应力路径3个方面进行分析.研究结果表明:浅层失稳是泥浆护壁成槽施工过程中槽壁整体失稳的主要形式,局部失稳多由槽壁土体砂性较重及槽段内泥浆液面波动过大引起;适当增加泥浆比重、提高泥浆液面标高、槽壁预加固、控制成槽机械地面超载及降低开挖对土体的扰动可有效保证槽壁的稳定;开挖后槽壁稳定性会随土体负孔隙水压力的消散而下降,成槽后应及时吊放钢筋笼并及早浇筑混凝土.
침대지하련속장성조시공과정중적조벽은정성급기실은현상,분별종지하련속장조벽은정영향인소、조벽정체급국부실은궤제、불동시공계단조벽토체적응력로경3개방면진행분석.연구결과표명:천층실은시니장호벽성조시공과정중조벽정체실은적주요형식,국부실은다유조벽토체사성교중급조단내니장액면파동과대인기;괄당증가니장비중、제고니장액면표고、조벽예가고、공제성조궤계지면초재급강저개알대토체적우동가유효보증조벽적은정;개알후조벽은정성회수토체부공극수압력적소산이하강,성조후응급시조방강근롱병급조요축혼응토.
Some key issues including inner and outer influencing factors of trench face stability,overall and local instability mechanism of trench face,and stress path of soil element near trench face are discussed in detail to investigate the trench face stability and instability performance during slurry trenching for diaphragm wall panels. The research results show that shallow ground collapse is the major trench face overall instability pattern during slurry trenching,and trench face local collapse is commonly caused by heavily sandy of soil and excessive fluctuation of slurry flux level. Some precautionary construction measures,including increasing unit weight of slurry appropriately,raising slurry fluid level,pre-reclamation of trench face soil,control of trenching machine overloading and manipulation of soil disturbance during slurry trenching,are the most effective countermeasures to ensure the trench face stability. The trench face stability decreases with the dissipation of negative pore pressure after slurry trenching. Therefore,reinforcement cages should be placed into trench in time and concrete should be casted as soon as possible to guarantee the trench face stability.