钢筋混凝土梁开裂后裂缝高度及钢筋应力分析

发布时间：2018-01-02 14:44

本文关键词：钢筋混凝土梁开裂后裂缝高度及钢筋应力分析　出处：《辽宁工程技术大学》2014年硕士论文　论文类型：学位论文

【摘要】：众所周知,裂缝是混凝土结构的常发病,即使是现在,对裂缝发生的抑制与防止,还没有一个十分有效的方法。本文对钢筋混凝土梁裂缝开展以及开裂后的受力性能进行了研究。首先,本文提出一种考虑混凝土材料强度随机分布的裂缝开展模拟方法。这种模拟方法由于考虑了混凝土材料强度的离散性,并以概率统计原理模拟混凝土的实际强度分布,通过移除单元的方法模拟开裂,从而更加合理地模拟出钢筋混凝土梁中裂缝的开裂过程。其次,通过模拟后处理技术提取出钢筋的应力值,并在此基础上分别模拟不同宽度、不同深度、不同位置的裂缝,得到开裂后梁内钢筋应力分布规律和应力最大值变化规律。结果表明,裂缝的存在仅仅影响裂缝截面处附近的钢筋应力,影响开裂后混凝土梁中钢筋应力变化的最显著因素是裂缝深度,而既有裂缝宽度对钢筋应力的变化影响很小,梁中钢筋拉应力最大值随裂缝出现的位置不同而变化,由于裂缝位置的影响,梁中钢筋应力最大值出现的位置也不同。最后,以实际的五根钢筋混凝土梁为例进行分析,通过裂缝高度的试验实测数据与模拟结果分析对比,论证了前述考虑混凝土强度随机分布的裂缝模拟方法在模拟裂缝开展高度方面的可靠性。同时,应用前面提出的方法将不同荷载水平下钢筋应力提取出来,根据钢筋应力水平对实际已开裂的钢筋混凝土构件的工作状态做出安全性评价。
[Abstract]:As everyone knows, the concrete structure crack is a frequently occurring, even now, to prevent the occurrence of cracks and suppression, there is not a very effective method. This paper made a research on cracks in reinforced concrete beams after cracking and carry out stress performance. Firstly, this paper proposes a method to carry out simulation considering crack strength of concrete materials randomly distribution. This method due to the discreteness of strength of concrete materials, the actual intensity distribution and probability statistics principle simulation of concrete, through the method of removing unit simulation of cracking, thus more reasonable to simulate the cracking process of the cracks in reinforced concrete beams. Secondly, through the simulation of postprocessing techniques to extract should be reinforced force value, and respectively based on the simulation of different width, different depth, different crack position, reinforced beam crack in stress distribution and The maximum variation. The results show that the existence of cracks affect only reinforced the stress near the crack section, the most significant influence factors of reinforced concrete beams after cracking stress changes is the crack depth, and both the change of crack width on the steel stress effect is very small, Liang Zhong reinforced the maximum tensile stress with crack the position varies, because of the influence of crack position, the maximum stress of reinforcement in the beam is different the position. Finally, the five reinforced concrete actual beam as an example, through the analysis and comparison of experimental data and Simulation of crack height results, demonstrates the strength of Concrete Considering Crack random distribution the simulation method to carry out the simulation of cracks in high reliability. At the same time, the application method of reinforced stress under different load levels will be extracted according to the level of the actual stress of reinforcing steel bar Make the safety evaluation of reinforced concrete members working state has been cracking.

【学位授予单位】：辽宁工程技术大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU375.1

【参考文献】