Deep Foundation Pit Support Program Based On Improved Analytic Hierarchy Process Preferred

Deep excavation engineering is very complex system engineering. The quality of its supporting scheme directly affects the progress, quality and cost of the project, which plays a vital role in the whole process of foundation pit construction. Although in recent years deep excavation engineering has been greatly developed with great applications, the domestic supporting scheme is still one-sided and subjective. Therefore, it is of great necessity and significance to find out a set of scientific, reasonable and workable scheme optimization according to the principles of safety and feasibility, economy, convenient construction and environmental protection.The scheme optimization of the deep foundation pit support scheme requires taking several factors into account, for example, safety, environmental protection, economy, short construction period and so on, as well as the mutual influence among all these factors. A feasible scheme can be made through the comprehensive verification of all aspects of the proposed options. Based on the traditional analytical hierarchy process(AHP), this paper carries out a detailed technical and economic analysis of the popular scheme of deep excavation and re-establishes an open evaluation index sign system of the scheme. It sets up the basic frame of the improved AHP with the application of single hierarchical arrangement and weight improvement of the index degree to determine the method, as well as the application of the assignment method of evaluation value. It also makes an evaluation optimization of the deep foundation pit support scheme with multi-step stages. The application of the practical construction shows that the method bases on the theory of system engineering and it makes some improvement on the traditional AHP, which makes it have more applicability and operability. This method reduces the difficulty for the experts to make the program evaluation, so that experts'opinions can be more accurately reflected. At the same time, the open and modifiable index system indicates the flexibility of the improved AHP and is more in line with actual needs. Besides, this paper makes a specific analysis of the reasons why the non-uniformity of evaluation is prone to occur during the weight calculation of binary comparison and puts forward the method of single hierarchical arrangement which is effective to solve the problem.