围堰封底混凝土钢护筒应力应变分析及厚度设计方法研究  

Research on Stress-strain Analysis and Thickness Design Method of Steel Casing for Cofferdam Bottom Sealing Concrete

作　　者：熊军 XIONG Jun(The 1st Engineering Co.,Ltd.of China Railway 12th Bureau Group,Chongqing 400037,China)

机构地区：[1]中铁十一局第五工程有限公司,重庆400037

出　　处：《工程技术研究》2024年第6期180-182,共3页Engineering and Technological Research

摘　　要：桥梁是国民经济建设和社会发展的重要基础设施,提升封底混凝土与钢护筒之间的界面黏结力对巩固桥梁基础中的围堰受力至关重要。钢护筒界面的环向变形和膨胀作用使混凝土处于局部受压的状态,对二者界面的黏结力起决定性作用。目前钢护筒厚度设计尚无完整明确的计算方法,仅依靠规范厚度取值过于保守。文章基于弹性体广义虎克定律,结合轴对称体系应力应变关系的对称性,建立轴向荷载下轴对称薄壁钢护筒的应变场数学模型。通过构建微元体的平衡微分方程、几何方程及本构方程,分析薄壁钢护筒在轴向荷载下的环向应变与位移关系,提出围堰封底混凝土钢护筒厚度参数设计方法,并通过ABAQUS大型通用有限元软件模拟验证了该设计方法的合理性。Bridges are important infrastructure for national economic construction and social development.Improving the interfacial bonding force between the bottom concrete and the steel casing is crucial for the stress of the cofferdam in the bridge foundation.The circumferential deformation and expansion at the interface of the steel casing cause the concrete to be in a locally compressed state,which plays a decisive role in the bonding force between the two interfaces.At present,there is no complete and clear calculation method for the thickness design of steel casing,and relying solely on the standard thickness value is too conservative.Based on the generalized Hooke's law of elasticity and the symmetry of stress-strain relationship in axisymmetric systems,a mathematical model of strain field for axisymmetric thinwalled steel casing under axial load is established.By constructing the equilibrium differential equation,geometric equation,and constitutive equation of the microelement,the circumferential strain and displacement relationship of the thin-walled steel casing under axial load is analyzed,and a design method for the thickness parameter of the cofferdam bottom sealing concrete steel casing is proposed;The rationality of the design method was verified through simulation using ABAQUS large-scale universal finite element software.

关 键 词：围堰封底混凝土 钢护筒 应力应变 厚度设计 数值模拟 

分 类 号：TV36[水利工程—水工结构工程]