超长框架结构温度应力的非线性研究

针对目前超长框架结构温度应力分析多集中于混凝土的线弹性阶段的情况，借助于通用有限元软件ABAQUS，采用混凝土“涂抹式”裂缝模型，对一个典型的超长框架结构在承受渐变温度荷载下的裂缝开展及应力变化情况进行了数值模拟，同时对目前工程实践中无粘结预应力筋进行了初步的理论研究．分析表明：温度应力是引起混凝土板开裂的重要因素并且具有明显的非线性；混凝土“涂抹式”裂缝模型在模拟较大结构的整体响应时，能够满足一般的计算精度．

Nonlinear research on temperature stress of over-long frame structure

As the analysis on the temperature deformation of over-long frame structures is usually focused on the basis of material's linear mechanic performance, the standard finite-element method strategy, based on the concepts of smeared cracking constitutive law, is used in the version implemented in the commercial code ABAQUS by HKS. A representative over-long frame structure's deformation under ramp temperature reduction is taken into account in order to simulate the cracking of concrete slab with proper numerical finite-element model. At the same time, a preliminary study about the concrete slab prestressed with unbonded tendons is also performed. Through the analysis, some significant information can be obtained for designing and further study: (i) the temperature stress does an important roll in simulating concrete slab's cracking process and has distinct nonlinear characteristic; (ii) concrete smeared cracking model can grasp structure's global mechanic performance.