【作者】 张雪冬；

【导师】 邹广平；

【作者基本信息】 哈尔滨工程大学 ， 结构工程， 2007， 硕士

【摘要】 近20年来，随着建筑材料和技术的发展，钢管混凝土结构逐渐被应用于建筑结构尤其是在高层建筑结构中。钢管混凝土按截面形式不同，可分为圆钢管混凝土，方、矩形钢管混凝土和多边形钢管混凝土等。矩形钢管混凝土相比圆形钢管混凝土有着与梁连接简单；稳定性能好：防火造价低等优势。矩形钢管混凝土柱在受压时，钢管和混凝土之间的相互作用相当复杂，因此，在受压的过程中，钢管和混凝土的受力和破坏情况都无法通过计算或者分析得出，在试验时，由于不能将钢管破坏掉观察内部情况，只能在试验结束后进行切割观测，在加载中的各个过程中，钢管和混凝土分别是怎么破坏的，钢管和混凝土之间的相互作用也无从判断。本文采用材料细观单元强度具有weibull分布的假设，认为细观非均匀性是造成准脆性材料宏观非线性的根本原因，通过使用利用该原理开发的RFPA软件对已经做过的矩形钢管混凝土柱轴压试验进行模拟试验，利用软件的功能，对钢管混凝土柱进行切剖观察，详细分析在整个加载过程中，钢管和混凝土之间的相互作用，以及在加载的各个阶段钢管和混凝土的破坏情况和受力情况。研究结果表明：(1)矩形钢管混凝土轴心受压柱具有良好的承载力和抗变形能力。(2)在N-ε曲线的第一下降段出现了钢管与混凝土的剥离的现象，下降段的快慢与钢管与混凝土之间的粘结力有关。(3)进入平缓段以后，构件的承载力与钢材的抗压强度有关系。同时，本文还对一种前人没有研究过的矩形钢管混凝土柱的偏心受载情况，采用适于轴压数值模拟试验的模型参数，进行了数值实验，并对此种受载情况下的钢管混凝土柱的极限荷载、破坏形态、过程、机理等特点进行了详细的分析。(1)刚开始加载时，最大应力集中在搭接面以下的一个三角形区域内。(2)这种情况的极限荷载是发生在钢管在搭接处的“撕裂”的时候。(3)在整个加载过程中混凝土出现了两条主要裂纹。(4)这种偏心受压造成的柱身的变形与偏心率有关。由于在矩形钢管混凝土方面，对偏心的研究相当少，希望以此来代替或者部分代替真实试验，以对钢管混凝土偏心的研究提出一些参考。更多还原

【Abstract】 In recent 20 years, as the architectural material and technical developments, the concrete-filled steel structures has gradually been applied in the architectural structure especially in the high buildings. According to different sections, concrete-filled steel tubular can be classified as concrete-filled circular, square, rectangle and polygon steel tubular etc. Compared with the circular concrete-filled steel tubular, concrete-filled rectangular steel tubular have some advantages: easier to connect with beams; better stability; and the low cost of fire prevention etc.When the concrete-filled rectangular steel tubular columns are compressed the interactions between steel pipe and concrete is very complicatedly, therefore, in the loading process, the stress and crack complexion of steel pipe and concretes can’t be attained by calculation or analysis. Because the steel pipe can’t be broken to observe the internal circumstance during the experiments, the results only are observe by incising the pipes after the experiments. In each stadge of loading process, the crack and interaction reasons of steel pipe and concrete respectively between steel pipe and concrete can’t be confirmed .In this literary, the assumption is used that the thin view unit material strength with Weibull distribution is used to explain reason of the submicroscopic non- linearity of quasi-brittle material is the thin view non- homogenization .By using the software which is developed on this theory, the experiment of concrete-filled rectangular steel tubular columns under axial compression is simulated. Using the software incising the concrete-filled rectangular steel tubular columns are observed, also the interaction between steel pipe and concrete, and the crack and stress circumstance of steel pipe and concrete in each step of loading process are analyzed . The research results indicate that: (1) The concrete-filled rectangular steel tubular columns have good abilities to resist loadings and transmutation.(2) The process of steel pipe peeling off the concrete columns appear in the first declining phase in the N -εcurve (3) When the entering the mild phase, the ultimate bearing capacity of the component is depended on the compress strength of steel pipe.Using the model parameters which are suit to columns under axial compression numerical simulative experiment, the numerical experiment of a kind of concrete-filled rectangular steel tubular columns under non-axial compression which haven’t been studied is made in this literary. And also the crack forms, compress strength, process, behaviors of concrete-filled rectangular steel tubular columns are analyzed detailedly. (1)At the beginning of loading, the major principal stress centralize in a triangle area under the lap.(2) The limit load of this case happens when the steel pipe is mangled in the lap area.(3)Two cracks appear in the loading process.(4) The deformation of column under this kind of non-axial compression is depended on the eccentric ratio. Because there is little research about concrete-filled rectangular steel tubular columns under non-axial compression, the numerical experiment is hoped to replace the true experiment partially or wholly, and put forward some references to the research on concrete-filled rectangular steel tubular under non-axial compression.更多还原