Though elasticity budget can realize control and appraisement function to many business levels, if there is not management platform where computer networks are constructed, this kind of budget management model is hard to be applied.

In this article, by expatiating on the concept and importance of the flexible design, and analyzing example and summarize corresponding methods of design, explaining that the introducing of the flexible design indicates a kind of reformation of conception which means taking the time factor into account and considering a building as a whole life process.

The elastic design of box boom can be made through two-stage stress theory.

The paper mainly set forth the construction method of subsiding pipes through river in reforming and renovating drinking water source in Dachang Nanjing,and introduced using stress testing in elastic installation of pipes.

The mechanical elbow,hot-bending bend,cold-bending bend and elastic installation can be used to handle pipeline corners in design of gas pipeline.

One kind of flexible budget method based on the activity cost management is presented,and its theory and algorithm of the method are discussed,its application feasibility for power plants is analyzed.