钢混叠合梁组合效应与剪力键抗剪性能研究-土木工程；桥梁与隧道工程专业论文.docxVIP

摘 摘 要 在现代工程实践中，钢混组合结构己得到了广泛应用。在大跨度斜拉桥领域， 钢混叠合梁以其重量轻、施工简单、造价合理等优势已被大量工程所采用。钢混 叠合粱通过剪力键将混凝土与钢梁连接成整体，使得它们共同工作，而剪力键则 主要承担二者之间的剪力，防止钢梁与混凝土之间出现滑移。本文主要针对“上” 字型钢混叠台梁，开展了以下两方面的研究： ①剪力键的抗剪性能一般可通过推出试验得到。本文将在现有推出试验的基 础上，通过选取合理的材料本构关系，考虑材料非线性影响，建立基于试验的有 限元模型，并分析试件的受力机理及破坏过程，计算比较试验值与有限元计算值 的差异。在计算值与试验值吻合的基础上，通过改变混凝土强度、栓钉直径、杆 长来对比分析栓钉剪力键的抗剪性能，得出影响栓钉抗剪承载力的主要因素，并 证明在线弹性阶段，栓钉和混凝土滑移较小(O．1mm内)，连接可靠。 ②以贵州乌江特大桥为工程背景，开展针对“上”字型钢混叠合梁的组合效 应研究。选取主跨跨中、L／8和L／4梁段为研究对象，采用MIDAS CIVIL建立全 桥有限元模型，并提取出在恒载和活载最大弯矩工况下的单元内力。在此基础上， 通过建立过渡模型，得到施加在局部模型上的边界条件、外荷载和端部内力。最 后采用MIDAS FEA建立主跨跨中、L／8和L，4节段的局部模型，分析不同荷载工 况下桥面板的受力机理和剪力滞效应，计算出桥面板有效宽度系数在O．586～0．994 之，间。 关键词：“上”字型钢混叠合梁，斜拉桥，推出试验，剪力滞，有效分布宽度 万方数据 AB AB STRACT In the practice of modern engineering，the steel concrete composite structure has been widely used．In the field of long span cable stayed bridge，the steel concrete composite beam has been used in a large number of projects for its advantages such as light weight，simple construction，reasonable cost and SO on．The steel concrete beams are connected to a whole by the shear bond，which makes them work together,and the shear bond is mainly responsible for the shear force between the two，to prevent the steel beam from slipping between concrete．In this paper,the following two aspects are studied： ①Shear strength of the shear bond is generally available through the introduction of the test．On the basis of the existing launch test，by selecting proper material constitutive relation，considering material nonlinearity,this paper will establish the model of the test，which based on finite element model，and analysis the test pieces by the stress mechanism and failure process，and comparing the differences between the test value and the calculated value．After the coincident of the value of test and calculation， this paper will conclude the main factors which influence the beating of shear bond by changing the concrete strength，stud diameter and rod length，and prove in the linear elastic segment，studs and concrete sl