Xin Li

The Analysis of the Concrete Lining Damage under Blast Load

Subway is an important part of city traffic system. Once terrorist attack happens in the subway, it might lead to strong response of concrete lining, which seriously threatens the safety of lives and properties. The analysis of the subway concrete lining damage under blast load has become an important question. By the means of finite element software AUTODYN, this essay simulates the highly nonlinear response and dynamic damage of concrete lining when 100kg TNT explodes different altitude above bottom of subway tunnel. It analyses attenuation of pressure and influence on the structure of concrete lining. The damage of concrete lining mainly concentrated in the vicinity of explosion source. Different explosive height will lead to different dynamic damage of concrete lining.

Research on the Centralized Procurement Mode of Construction Projects Materials

Aim: To strengthen management cost of construction projects, reduce procurement cost of materials, guarantee materials quality and to promote the profitability of the project. Approach:Adopt scientific centralized procurement implemented by construction enterprise headquarter.Result: It not only reduces materials procurement cost, but also improves the quality of procurement, which, guarantee the project quality and promote the profitability of both the project and the enterprise that carries it out. Conclusion: The centralized procurement mode of construction project materials can effectively reduce construction cost and promote the profitability of both the project and the enterprise that carries it out.

Cost of Project Research Based on Fuzzy Math

The speed and accuracy of project cost are improving with the development of building construction technology and management, however, it often takes a long time to estimate the proposed project. This essay bases on the method of fuzzy math, we researched quick estimating of project cost in order to provide an effective method in evaluating project cost on proposed project.

Analysis of the Aluminum Foam Protective Effect under Blast Load

Terrorist attack is a great threat to the safety of the city. Due to particularity of the subway tunnel, the concrete lining will produce the strongly nonlinear response and dynamic damage under blast load, even collapse of the concrete lining structure. Protection technology of the concrete lining under blast load has become an urgent problem to be solved. By the means of the finite element software, this essay simulates the highly nonlinear response of concrete lining with aluminum foam. Aluminum foam has been widely used in the field of disaster preventive and mitigation. Application of the aluminum foam under blast load can absorb a large amount of impact energy and reduce the peak value of pressure in the concrete lining.

Analysis of Affecting Factors of Ground Deformation Based on Shield Tunnel Excavation

The shield tunnel method is a way that widely used in tunnel build. However, the ground surface displacement and deformation because of tunnel excavation will bring a series of affections in our engineering. By using the finite element model of different tunnel excavation depth, different elastic modulus and different tunnel diameter of the tunnel, we predicted it correctly. Finally, we get the relationship between the surface displacement and the depth of tunnel excavation, diameter, strength of soil.

Shield Lining Segments Design Research Based on Characteristic Parameters

As we all know, the thickness of the shield lining segments, reinforcement ratio and other parameters of the design have a direct impact on the economics of the project. We have taken a model of parametric analysis simulation and by the way of changing the parameter of lining segments to research their deformation and stress. Finally, we get the relationship between the characteristic parameters and the deformation and stress of the lining segments, and summed up the characteristic parameters which are more influential.

Through the Analysis of the First Stage Project of Shenyang Subway Line One, Summarizing Effective Measures of Reducing Cost of Subway

From analyzing project cost of the first-stage project of Shenyang subway line one,there are several important factors affecting the cost of Shenyang subway line one. By the analyzing cost of land pulling down,design fees,power supply system,vehicle,shield machine and laying mode and comparing with cost of other urban subway. Finally we summed up the effective measures to reduce the cost of subway .

Study of Subway Construction Management Mode

From all kinds of project management mode, the characteristics of the model change reason and the opting of our country, the construction of the existing metro management mode has summarized. Domestic existing metro construction management model is divided into four categories, and the various modes of in-depth analysis, analysis of subway construction management mode changes and the reasons for our subway construction management mode selection recommendations.To improve the management level of Chinas subway construction in order to provide a reference.

Numerical Simulation of Lining’s Mechanical Behavior in Subway Tunnel

The surface settlement and tunnel lining has a great relationship.To better understand the influence of surface deformation caused by tunnel lining and lining’s stress state,base on Finite Element Method,using ABAQUS Finite Element Analysis Software, analyzed the change of surface displacement and the lining of stress and deformation,respectively,with and without lining.Through the comparison of two cases, the surface settlement and horizontal displacement can be effectivly reduced.The range of influence caused by excavation is greatly narrowed.Because the role of soil,the compressive stress is beared by lining,and the maximum stress is located at both sides of arch waist. These will be referenced for future design and construction.

Integrative Fuzzy Set Pair Model for Safety Pre-Evaluation in Construction Stage

The integrative fuzzy set pair model, established by set pair analysis (SPA) and fuzzy hierarchy analysis, was introduced to pre-evaluation of security states in the construction stage. Two relevant sets, evaluation index and dangerous standard, were analyzed and calculated in terms of the identity, discrepancy and contradistinction[1]. The indices and weights were determined by Delphi and fuzzy hierarchy analysis respectively in order to establish the integrative fuzzy set pair model of construction stage. Finally, the model was applied to the case study of Shenyang sewage treatment plant and the results demonstrated that the method proposed in this present paper is satisfactory.