Research On Design Change Of Electrical Mechanical Engineering Of Rail Transit Project

Construction of many urban rail transit projects are being carried out in China.In order to give passengers with comfortable travel conditions.The constructors of rail transit project paid more and more emphasis on the humanized design.ventilation and air-conditioning system,water and drainage system and low voltage distribution system have close relationship with ride comfortability,which has attracted more and more attention from owners.Because of multiple interfaces between specialties and complicated construction situations in mechanical and electrical engineering,a large number of design changes exist in rail transit project,which increase the investment of the owners substantially,and affect the achievement of project management objectives significantly.Many researches on rail transit project and changes of mechanical and electrical engineering can be found respectively,but little research has been conducted in mechanical and electrical engineering of rail transit project.In this paper,case studies and questionnaires was adopted to do some researches on Suzhou Rail Transit Line 1 and Line 2.Firstly,the relevant literature at home and abroad were read,and existing research results of about design changes of mechanical and electrical engineering in rail transit project were summarized,at same time,the concept of mechanical and electrical engineering was elaborated briefly.Secondly,combined with the results of surveys and statistical analysis,management issues and measures in design changes of Suzhou Rail Transit Line 1 was analyzed.Finally,in order to validate the design change management measures,a comparative analysis about the number and amount of design changes in Line 2 was conducted.The results shows that in the mechanical and electrical engineering of rail transit project,low voltage distribution engineering is prone to generate design changes(53.1%).Design quality is the main reason which cause design changes.The accuracy of data about the interface is the most important factor affecting the quality of design(43.3%).In order to control design changes,the owner extended the design lifecycle,improved the quality of designers,defined the responsibilities between the interfaces of different disciplines more clearly,strengthened the review of design and technical explanation more effectively,etc.The results showed that after taking relevant measures,compared to line 1,the number of design changes in Line 2 decreased by 65.3% and the total amount of changes are only43.2% of Line 1.The results of this paper is not perfect.Only 30 questionnaires collected in this paperwhich cannot reflect the overall opinions.In addition,which management measures are most effective in controlling the design changes in Line 2 are not quantitatively analyzed.This above will be further strengthened in the future research.