Advanced Materials Research Vols. 838-841

Abstract: Base on visco-elastoplastic theory, using Laplace transformation the asphalt pavement parameters of viscoelasticity model and visco-elastoplastic model are converted into parameters of prony series, the rutting deformations of asphalt pavement are analyzed by using ANSYS, the influence of load, material temperature and loading cycles are considered. The research shows that with the increase of loading cycles, the rutting deformations of visco-elastoplastic model gradually large than the results of viscoelastic model, both the load and temperature have a influence on the rutting deformations of asphalt pavement.

Abstract: Tongluoshan expressway tunnel passes through coal mined out area. It is an extra-long expressway tunnel with high-gas, so construction ventilation is the key in this project. Combined with the theoretical calculation and the actual situation of Tongluoshan Tunnel, the forced ventilation is taken as the major way of construction ventilation. Based on the calculation of required airflow, gas distribution in work area and calculation of air duct resistance and tunnel resistance, the configuration of fans is optimized, thus the construction ventilation of each section have been determined.

Abstract: In this paper, theoretical basis and feasibility of implement of utilizing epoxy asphalt in airport pavement construction are analyzed on the purpose of choosing a satisfying material. Afterwards, we tested the high-temperature and fatigue performance of the mixture which is a major concern during airport pavement design , and the results show that the performance of the epoxy asphalt mixture is very excellent compared to conventional asphalt mixture. At the end of this paper the author put forward the problems to be solved and studied of to promote the application of epoxy asphalt mixture.

Abstract: Rock slopes are always distributed along roads, due to the discreted distribution and small scale, detailed mechanics parameters of the slopes are difficult to obtain. Thus, the existing analysis methods, like Q-system classification, RMR classification, SMR evaluation system, and CSMR method are not suitable for analyzing rock slopes. In this paper, an evaluation model for slope stability classification of ordinary roads in Liaoning province is proposed based on two-level fuzzy comprehensive evaluation. Thirteen genes that belongs to four factors are selected as predictive factors for the evaluation model. Membership is assessed by expert assessment method and the weight value of affecting factors is determined by inverse analysis method in evaluation model. A total number of 129 rock slopes is studied using this model and results are consistent with the experts' in situ evaluation, which proves this method reasonable and practical.

Abstract: Set pair analysis is a combination of qualitative and quantitative methods used in decision-making. Aiming at the irrelevance of each indicator, an evaluation model of bolt and wire mesh support scheme of roadway based on set pair analysis is set up and a relativity to optimal scheme which combines multiple indicators as well as its set pair situation are applied to describe the comprehensive benefits of bolt and wire mesh support scheme. Evaluation results of three optional support schemes in a mine of Yaojie Coal and Electricity Co., Ltd are obtained using this method, and an optimal scheme with the best comprehensive benefits is determined.

Abstract: The excavation of foundation pits near existing railway will cause innegligible deformation for the railway line. This paper first conducts numerical simulation for the impact of the excavation of foundation pit for a building close to existing railway lines on the deformation of the railway, and arrives at such conclusions: the excavation of foundation pits has a great impact on the railway lines. The amount of vertical deformation is beyond the requirements of relevant regulations. Accordingly, the foundation needs stabilizing treatment. After the reinforcement of high pressure jet-grouting pile, the maximum vertical deformation decreases obviously to meets the requirements. On this basis, the paper analyzes the reduction amount on different phases of the excavation to work out their respective reinforcement effect. After that, it compares the results with the real data collected during the construction to test the correctness of the model, finds out the major periods during which the vertical deformation occurs as well as the amount of deformation in each period, and points out the worst period for railway deformation during the excavation of foundation pit.

Abstract: It is inevitable to make the new-built highways under-pass the existing railroad by virtue of high-speed development of the transportation in China. Since the relevant surveys on the safety risk evaluation of this kind of the project are lacked at this current stage as well as the limited referential sample data, the survey is to research the factors of safety risk and the self-characteristics as well as to build up the safety risk evaluation model by means of support vector machine plus the analysis with the help of the project example. It turns out that the analyzed result by means of the model has the propinquity with the expected result, as means the model with the limited samples is characterized of improving the objective correctness of the evaluation result in order to supply a scientific method for the safety evaluation of this kind of projects.

Abstract: A simulation model based on Petri nets is presented to evaluate the performance of the transfer procedure for passengers in urban railway transit hubs. A systemic and physical description of urban railway transit hubs is illustrated by Petri nets model. The simulation model was verified through a real case to analyze the evolution of the number of transfer passengers on the facilities and the equipments and measure the transfer time for all the transfer passengers in the hubs. It is showed that a potential and effective method is provided to evaluate and optimize the design of the transit hubs.

Abstract: Exploring into the limitation of the application of SLP in the spatial layout planning of Logistics Park, this paper proposes to build a new model with perfect interior and associated exterior under the guidance of SLP and Hungarian method. The comprehensive interrelation of the function areas can be got on the basis of using SLP. Hungarian method can add the analysis on the correlation of the function areas and peripheral transportation. Finally, this paper proves rationality and availability of this method by taking the spatial layout of Chengdu international railway container logistics park for example.

Abstract: Based on the analysis and summary of 19 PEIA cases of urban rail transit (URT) planning, this paper pointed out the major problems on PEIA of URT in practice, such as the depth of environmental impact prediction was inadequate, Optimal comments to URT Planning were not operational, and Public Participation was not representative etc. In response to these problems, this paper put forward some suggestions on both of regulating the technical means of PEIA for URT and improving the capacity of PEIA technical personnel. It could be helpful to improve the scientificity and practicity of PEIA for of urban rail transit planning in China.