Study On Identification Of Key Components Of High Rise Steel Structure Based On Sensitivity Analysis

The number of the researches of the collapse of the steel structure is increasing, along with a large amount of the steel structure has been builded. To avoid the collapse of the structure, it is important to distinguish the pivotal constructional elements. So this article introduces the sensitivity coefficient to distinguish these things. According to the number of sensitivity coefficient, we could determine the pivotal constructional element. This article taked seven story steel frame as the model, we could distinguish the pivotal constructional elements through the sensitivity coefficient, and compared the differences of the support frame and no support frame. The software which was used in this article is ANSYS15.0. It was used to analyse the problem through the nonlinear static. The main analytic content included as below:1. Through the analysis of nonlinear static of the corner columns, side columns, central columns on the ground floor, we can get the sensitivity coefficient of every constructional element.2. Through the analysis of finite element of the corner columns, side columns, central columns, girders on the standard floors, we can get the sensitivity coefficient of every constructional element.3. Through the analysis of sensitivity of the corner columns, side columns, central columns, girder on the top floor, we can get the sensitivity coefficient of every constructional element.4. According to the number of the sensitivity coefficient, we can determine the pivotal constructional elements.5. Compare the differences of the support frame and no support frame.Major accomplishment of this paper are as follows:1. Through the analysis of steel frame of the ground floor, we concluded : the sensitivity of the corner columns are higher, the sensitivity of the interior columns in long side direction are higher. the sensitivity of the interior columns are higher.2. Through the analysis of steel frame of the standard floors, we concluded : the sensitivity of the corner columns are higher than side columns, the sensitivity of interior columns in the long side direction are higher. the sensitivity of the interior columns are higher than central columns. When the secondary girders which were put in the long side direction, the sensitivity of the girders in the short side direction are higher, but there are little differences between them.3. Through the analysis of steel frame of the top floors, we concluded : the sensitivity of the corner columns are higher than side columns, the sensitivity of interior columns in the long side direction are higher. the sensitivity of the interior columns are higher than central columns. When the secondary girders which were put in the long side direction, the sensitivity of the girders in the short side direction are higher, but there are little differences between them.4. Through the analysis of constructional elements of the ground floor, standard floors, top floor, we concluded that the sensitivity of the columns are more higher than the girders. With the increase of the altitude, the sensitivity of the columns which are in the same position with the former has decreased, but those girders show just little differences.5. According to the sensitive level, we divide sensitivity into two levels : first-degree and second-degree, the first-degree is more important than second-degree. So the sensitivity of columns are belong to first-degree, and the sensitivity of the girders are belong to second-degree. We believe that those constructional elements which have higher sensitive level are pivotal. Therefore, the columns are pivotal. Especially, the sensitivity of the corner columns in each floor are highest, so we should strengthen the protection of the corner columns in design.When the support of frame is added, the deformation of the columns that in each floor has decreased, and the sensitivity of these columns has reduced too. However, the deformation and the sensitivity of the girder that in each floor still remain unchanged. But the sensitivity of the columns has decreased because of the addition of the support frame. Due to the columns are pivotal, the sensitivity of all pivotal constructional elements has decreased. Adding the support of frame could improve the stability of structure overall.