Research On Optimization Of Multi-layer Reinforced Concrete Frame Structure

When reinforced concrete frame structure is designed according to the traditional method, the use of building function and the relevant norms are mainly considered, while the economy of structure is ignored. Once the design meets the requirements, there’s no adjustment for the structure, which causes a huge waste of resources. With the real estate market competition intensified, construction enterprises pay more and more attention to control the cost of projects. Part of them optimize the structure in the design stage with the help of the optimizer. However, in the optimizing phase, it mainly relies on the engineering experience of the engineer, which lacks theoretical basis.This paper firstly introduced the basic theory of structural optimization, and divided the frame structure into a relatively independent beam and column members according to the idea of the part optimization. Then established the optimization model of the component. After that, it wrote the discrete variable optimization design program for the structure by the use of MATLAB software. In this program, the section size of the component and the concrete strength grade was the design variables. The relevant provisions of the specification were the constraint conditions. The goal of optimization was to achieve the lowest cost. Then using the optimization design procedure to optimize a certain frame structure of the community activity center in Chengdu, which verified the practicability of the optimization program. Next step, this paper optimized the column layout of L-shaped plane frame structure at the corner. And then optimized each column layout scheme taking use of the program. In this step, the economical comparative analyses were also made. Finally, the optimization model of simply supported beam was established, and the economical high span ratio and economic reinforcement ratio of frame beam were presented.The main conclusions of this paper are as follows:(1) The optimal design program can significantly reduce the cost of the frame structure and meet the design requirements, which has a high practical value for the project.(2) When the concrete strength grade of the beam is in the range of C25-C35, the strength grade of concrete has a little influence on the total cost of interlayer beam.(3) It is more economical to arrange beam in only one direction when the L-shaped plane frame structure is in the two direction of uniform arrangement at the corner.(4) It is more economical when the frame beam’s high span ratio is from 1/8 to 1/18, the reinforcement ratio is from 0.6% to 1.2%. And the strength grade of concrete has a little influence on the height span ratio and reinforcement ratio of the frame beam.