This paper analyses the mechanism of extra earning by which the contractors make unbalance bid by utilizing engineering change, reaches two key nodes, and describes the process of engineering change with the help of the idea of triggering.On the basis of these, it constructs a FSD model which contains the forecast of engineering change, the simulation of the appearance of the expected engineering change and the design of the Bidding strategy.This model can be used as theoretical basic and provide contractors a standardized operation process of unbalanced bid.

In order to improve the design level of domestic outfit stylist and the efficiency of design, solve the current domestic outfit design facing the severe challenge in the management and use of advanced information technology tools BIM technology to solve these problems, considered from the perspective of strategic development to establish a set of domestic outfit design system based on BIM technology, undertook unity 3D home outfit design, unified price management, established a complete enterprise knowledge based on the management, integrated from designing the figure to calculate the amount of domestic outfit design management system. BIM technology on the application of domestic outfit industry helps to promote the development of domestic outfit enterprise scale economy, especially improves the competition ability of the enterprises in the area of domestic outfit design tools. This paper was under the home decoration design company of domestic outfit design system based on BIM technology implementation, solved single design tools of the traditional decoration desiging industry and concentration of the enterprise resource management problems, realized the three-dimensional decoration design based on BIM technology tools, design resources unified management, long-term accumulation into an outfit enterprise intangible assets, improved the efficiency of the domestic outfit design and the decoration enterprises′ competitiveness.