Design Method Analysis Of The Load-Bearing Capacity And The Ductility Of Special-Shaped R.C. Columns

To make up for the deficiency of design and analyse in special-shaped columns ,this paper mainly study on the two aspects of special-shaped R.C. columns which are the load-bearing capacity and the capability of ductility. It brings forward a full design method by considering special-shaped columns both load-bearing capacity and tractility. To more specific as belows:1 Bring forward a method which design special-shaped columns based upon envelope of ultimate load-bearing capacity.At first, two problems in current analysis method for front section in special-shaped R.C. columns were discussed: 1) the safety problem ,which is caused by the discrimination between rectangle and special-shaped section. Sometimes status of the most dangerous section may sometimes not be contained by the combination of inner force. 2) The speed of the special-shaped columns analysis and calculation.Based on these two problems, the paper finds the way how to design the section of special-shaped columns by using ultimate load-bearing capacity. It can easily solve problems of security and calculate speed, and using program and theory fulfill all of these.2 Test through experiments and analysis of examples:The paper designed the program based upon this method, and discussed as below:(1) To test veracity and rationality of the method by compare it to the real results.(2) To describe the infection by traditional combination of the internal force, and different consideration in this paper.(3) To prove the feasibility and the practicability by test many different example of the special-shaped columns.(4) By comparing other method the calculation of the special-shaped columns the method of this paper is more practicable.3 To compare the difference between ductility of the single component and the structural components:At first, this chapter analyzes the connection of the concrete and steel bar the solution of the crack and the rule of destroy by set up finite analysis model. By calculate the example, the result can reflect the law which can explain the rule of destroy of the 'Z'-shaped columns. Secondly, by using the way of finite analytical simulation, it can easily discuss the difference between ductility of the single component and the structural components. It roughly analyzed the 'L'-shaped columns, and brought forward somedifference problem in ductility.4n Discussion about limit of axial compression-ratio and design in ductility of special-shaped columns:This chapter discussed about main factors in the limit of axial compression ratio and the ductility of special-shaped columns, and then brings forward a method that to improve the ductility by increasing axial compression-ratio is limited in current ductile design special-shaped columns analysis. From all of these, this chapter bring forward ductile design method which can avoid destroy. To some degrees, it can easily avoid the limit that caused by using axial compression-ratio to design ductility. It forms a integrated method in designing the special-shaped column by using all of these and synthetic consideration of axial section in special-shaped column.