【作者】 辛佩龙；

【导师】 许颖； 朱继华；

【作者基本信息】 哈尔滨工业大学 ， 土木工程， 2010， 硕士

【摘要】 随着冷弯薄壁钢的不断发展,越来越多截面型式的钢构件在结构中得到应用。对于一种新型截面钢构件的推广应用,需考察现行规范中的设计方法对其是否适用,并通过研究得出适用的设计方法来指导其在工程中推广应用。本文基于实验数据,对冷弯薄壁钢空心类椭圆截面轴压构件、受弯构件以及压弯构件进行了非线性有限元数值模拟,并基于数值模拟结果对此类构件的设计方法进行了研究;考察了我国以及国外现行规范中有效宽度法对此类构件设计的适用性,并提出采用直接强度法对此类构件进行设计,得出了适用于此类构件的设计方法,为此类构件在工程中的推广应用提供了设计基础。本文研究的内容及成果如下:1)采用Abaqus建立了冷弯薄壁钢空心类椭圆截面轴压构件、受弯构件以及压弯构件的非线性有限元数值模型。将模拟结果与试验结果进行了比较,考察有限元分析方法模拟此类构件力学性能的可行性与可靠性。有限元数值模拟的结果表明:采用Abaqus建立的数值模型可以较准确地模拟冷弯薄壁空心类椭圆截面钢构件的极限承载力和失效模式等力学性能,在很大程度上可以替代昂贵、费时的试验,是一种经济、高效的研究方法。2)利用此模型进行了大量的参数分析,建立了包括100个轴压构件、36个受弯构件以及200个压弯构件的参数分析数值模型。为设计方法的研究提供大量的研究对象和数据。3)基于试验和参数分析结果,对此类构件的设计方法进行了研究。对于现行规范中无法考虑半圆板件有效宽度的计算等问题,本文基于试验和数值模拟情况做出了一定的假定进行设计计算。同时提出采用基于全截面分析的直接强度法对此类构件进行设计。通过对各国规范及直接强度法计算结果的比较分析,最终得出了适用于此类构件的设计方法。研究表明:基于本文中的假定进行设计的我国及国外现行规范不能准确地计算此类构件的极限承载力;而采用直接强度法进行设计的计算结果与试验和有限元模拟结果比较吻合,可靠度指标较好,适用于冷弯薄壁空心类椭圆截面钢构件的设计。更多还原

【Abstract】 With the rapid development of cold-formed steel structures, more and more types of cold-formed steel section members have been applied in the structure. For a new types of section members, it is necessary to investigate the applicability of existing design specification to promote its application in engineering. A research has been performed on the numerical simulation and design of cold-formed steel oval hollow section members to investigate the applicability of existing Chinese and international design specification for the new sections. A new applicable design method called Direct Strength Method (DSM) has been used to design in this paper. It is suitable for the design of such components and provides a design basis for the promotion of this component in engineering.The content and results of this study are as follows:Firstly, non-linear finite element models of column, beam and beam-column have been developed using Abaqus. The numerical results were compared with the test results and it is shown that the numerical model accurately predicted the structural behavior of the compression members. It could replace the expensive test and could be an economical and efficient method in the research to a large extent.Secondly, parametric study including 100 compression members, 36 bending members and 200 beam-column members with different cross-section dimensions and lengths were performed using the verified model. It provided a lot of objects for the following design research.Finally, based on the results of the experiment and numerical simulation, the design of such section member has been studied. Some assumptions were made based on experiments and numerical simulations as a result of no stipulation about the effective width of the semi-circular in the current design specifications. Direct Strength Method based on full cross-section was proposed. The test and numerical strengths were compared with the design strengths calculated using the current code and direct strength method. It is shown that the direct strength method can be used for the design of cold-formed steel oval hollow section members under axial compression.更多还原