摘要
曲线顶管底幕法是一种新型的水下沉船打捞技术,因该工法采用了新型竖向小曲率半径顶管,其掘进过程中变深度理论顶推力的计算及对船体及周边的扰动情况还尚未明晰。在分析了管-土相互作用的基础上,通过简化管-土的剪切破坏作用,建立了更符合实际情况的管-土相互作用模型,推导了竖向曲线顶管的理论推力。并将该理论模型对应推力计算结果与现场实测数据以及前人既有理论公式进行对比,验证了推力计算模型的合理性及准确性。同时,建立精细化的曲线顶管底幕法水下沉船打捞有限元计算模型,将理论推力作为模拟输入参数代入数值分析,由此获得了在不同施工顺序下曲线顶管底幕法顶进过程中周边土层和沉船的扰动分布规律。研究结果表明:水下曲线顶管顶进时主要是机头后方的管节与土体相接触并发生摩擦,是顶推过程中贡献最大的阻力源。单侧施工与对称施工完成后会对土体产生-15~-16 cm的竖向扰动。但是对称施工引起的土体扰动更均匀对称,对沉船造成的扰动与偏转也更小。提出的水下曲线顶管底幕法推力计算模型与现场实测结果更加接近,研究成果可为水下曲线顶管底幕法的推力计算及精细化分析其施工扰动提供理论依据。
Curved pipe jacking bottom curtain method is a new type of underwater shipwreck salvage technology.As this method adopts a new type of vertical small curvature radius pipe jacking,the theoretical calculation of variable-depth jacking force during the tunneling process and the disturbance to the hull and surrounding areas remain unclear.Based on the analysis of pipe-soil interaction,a more realistic pipe-soil interaction model is established by simplifying the shear failure of pipe and soil,and the theoretical thrust of vertical curved pipe jacking is deduced.The calculated thrust values from this model are compared with field-measured data and existing theoretical formulas,validating the rationality and accuracy of the proposed thrust calculation model.Additionally,a refined finite element salvage model for curved pipe jacking bottom curtain method is developed.By incorporating the theoretical thrust as input parameters into numerical simulations,the disturbance distribution law of surrounding soil layer and shipwreck during jacking process of curved pipe jacking bottom curtain method under different construction sequences is obtained.The results show that when the underwater curved pipe jacking is advancing,the pipe joint behind the shield head is mainly in contact with surrounding soil and causes friction,which is the largest resistance source in the jacking process.Unilateral construction and symmetric construction result in vertical ground settlements of−15 cm to−16 cm upon completion.However,symmetric construction induces more uniformly distributed ground disturbances,with significantly reduced disturbance and deflection on the shipwreck compared to unilateral methods.The thrust calculation model of the underwater curved pipe jacking bottom curtain method proposed in this paper is closer to the field measurement results.The research outcomes provide a theoretical basis for jacking force calculation and refined assessment of construction-induced disturbances in underwater curved pipe jacking bottom curtain method.
作者
李培楠
刘学
戴泽余
翟一欣
张弛
寇晓勇
范杰
甄亮
王长虹
LI Pei-nan;LIU Xue;DAI Ze-yu;ZHAI Yi-xin;ZHANG Chi;KOU Xiao-yong;FAN Jie;ZHEN Liang;WANG Chang-hong(School of Environmental Science and Engineering,Donghua University,Shanghai 201620,China;Shanghai Tunnel Engineering Co.,Ltd.,Shanghai 200032,China;Shanghai Highway Bridge(Group)Co.,Ltd.,Shanghai 200082,China;School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China)
出处
《岩土力学》
北大核心
2025年第S1期403-418,436,共17页
Rock and Soil Mechanics
基金
上海市“科技创新行动计划”社会发展科技攻关项目(No.21DZ1201100)
上海市“科技创新行动计划”优秀学术/技术带头人项目(No.23XD1431200)
关键词
曲线顶管底幕法
水下沉船打捞
顶推力计算模型
理论解析法
施工扰动
curved pipe jacking bottom curtain method
underwater shipwreck salvage
thrust calculation model
theoretical analysis
construction disturbance
