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The power cable infrastructure is a high risk system in a city, and various risk factors are in the mutual influence, which are distributed throughout the whole process of project management. Based on the composition and construction features of power cable project, this paper proposed the process of security risk identification, and the safety risk evaluation index of power cable system has established, and the quantitative risk assessment and classification. By identifying the main risk of power cable system, this paper proposed strengthening the monitoring and management of risk, and the effective risk countermeasures to avoid, transfer and control risk.

Compared to traffic accidents on sections of open road, the consequences of traffic accidents are worse in a tunnel, especially for a long tunnel. In order to improve the safety performance of long tunnels in China, the effects of geometric alignments of long tunnel entrance on average speed and speed difference for passenger vehicles and trucks, as well as the heart rate increment of drivers, are analyzed using statistical analysis and regression method. The research results show that the effects of geometric alignments on average speed and speed difference at the tunnel entrance section for passenger vehicles is relatively small and the effect on average speed and speed difference for trucks is relatively large. The combined influence of the horizontal and vertical alignment of tunnel entrance on heart rate increment of drivers is deterministic. Based on research findings on the speed difference of vehicles and heart rate increment of drivers, consistency evaluation methods and corresponding evaluation criteria for long tunnel entrance section are proposed. These methods are helpful in optimizing geometric design of long tunnel entrance sections.

On the basis of analyzing the transportation network design problem, a bi-level objective model is proposed. The upper model considers the views of a transportation planner to design a more optimal network structure; the lower considers the views of a network user to find the shortest path. This study uses an improved stepped-up chaos optimization algorithm to calculate the model. The new algorithm is based on the characters of traditional chaos optimization algorithm, through constantly shrinking the searching area and adjusting parameters to make the searching results converge upon the optimal numerical value faster. The authors use MATLAB programming to calculate the example network. The result shows that the improved model and algorithm are all effective. Both the model and algorithm can be used to provide scientific guidance for transportation network optimization.

Many methods and eye movement indexes were used to describe drivers' visual search. But drivers' visual search behavior should be a four-dimensional index, which not only includes fixation distribution, but also includes fixation duration.Thus, it is difficult to find the regularity of drivers' visual search behavior by single factor analysis for drivers' eye movement index. In order to quantitatively analyze the characteristic of drivers' visual search behavior, the paper introduces a new index, called the Visually Interesting Region (VIR). VIR includes area and barycentric coordinates two parameters, and is a new index of visual information search while driving. According to the analysis, the paper found area of VIR and barycentric coordinates separately has correlation with horizontal alignment and traffic flow, of VIR mainly affected by highway alignment and traffic flow.

The driver's subjective perception of road safety during driving has a very important influence on traffic safety. The paper introduces the study of a driver's subjective perception of road safety in driving. It analyzes the production mechanism, three kinds of generating patterns, the influencing factors, and the characteristics of the influence on traffic safety. The paper lays a good foundation for further research on how to improve traffic safety based on driver's subjective perceptions of road safety.

In order to prevent overtaking and speeding and improve road safety, a new median facility was installed in a two-lane bi-directional tunnel. The objective of the research presented in this paper was to evaluate the safety and practical effect of the facilities. The observations of traffic operation and vehicles speed were carried out on a tunnel with the facilities and a tunnel without the facilities. The result showed that the facilities had achieved the anticipated effect on overtaking prevention and reduction of mean speed and speed standard deviation.

In order to make the deceleration length more practical without compromising safety, a new concept of left-turn lane design method was produced and used on a new four-lane highway in Yunnan Province. The authors observed vehicles speed on a selected left-turn lane set up with the new concept and obtained speed data of normal section and split point. The authors then analyzed the data by means of descriptive statistics analysis, the paired-samples T test and ANOVA. The result showed that the length of left-turn lane could be shorter than the specification without compromising comfort and safety. The speed used to determine the deceleration length could be reduced by 15km/h.

Research on design speed of truck escape ramp (TER) was carried out in order to make it more cost-effective and safer. The data of 9 TERs of Yuanmo Expressway has been collected. Back analysis method was brought forward and adopted to analyze the speed of out-of-control vehicles entering arrester bed. According to distribution of vehicle speed data, the speed of vehicles losing braking capabilities that met a probability were obtained, which could be used to determine TER design speed. The result also showed that 99 percent of vehicles’ speed was lower than 102.2 km/h, which was much lower than the speed of 130 km/h introduced internationally. The TERs designed by using this result has opened to traffic for one year. No traffic accidents occurred yet caused by improper settings of TER.

Aimed at the hot topic "vehicle restriction in Beijing," this paper set up a systematic monitoring and evaluation system. Firstly, this paper reviewed the experience and effectiveness of the implementation of travel demand management (TDM) in the world, particularly Mexico City’s implementation of a 10-year-old motor vehicle restriction measure. On this basis, according to Beijing’s vehicle restriction multiple effects, this paper established a set of comprehensive evaluation systems including traffic, environmental, and social impact. Through the methods of floating car systems, congestion evaluation indices, public transportation IC cards, public opinion surveys, and web-based surveys, systematic data were analyzed. The data shows that the traffic and air quality has improved, especially the traffic congestion The public strongly supports all improvement within the traffic system. This paper will provide an important reference for decision-making and other cities’ traffic management research and implementation.

This paper compares three reinforcement patterns of Section K19+250-∼K23+710 of Yichang (in Hubei Province)—Wanzhou Expressway: Scheme A uses CFG (Cement-Flyash-Gravel) pile with 15.5m as its length; Scheme B adopts long-short pile with CFG pile (15.5m) as the long pile and CDM (Cement Deep Mixing) pile (13.5m) as the short pile; Scheme C employs CDM pile with the length of 15.5m. The method of nonlinear finite element of ABAQUS software is applied to a contrast analysis of the effect and mechanisms of different ground treatment patterns. The results showing the settlement of pavement and embankment base are discussed. The lateral displacement of levee toe are at a minimum in Scheme A, increases in Scheme B and at a maximum in Scheme C Pile-soil stress ratio is highest in Sheme A, and at a minimum in Scheme C. In Scheme B, long-short pile stress ratio, which is always higher than 1, first increases and then decreases, indicating the load transfer of piles with different rigidities is interacts and the stress can be mutually adjusted. The excess pore pressure is positive correlated with fill load of embankment: within the same period, the excess pore pressure gradually declines with the increasing depth. The geogrid relates to load and position, load bearing of pile soil and geogrid is a dynamic process when the embankment load is the same. The load mechanism of pile-net composite foundation agrees with the related monitor data of in-situ test, which provides the basis for the design of the soft soil foundation.

Through the bus rapid transit ( BRT) operating facilities, operational efficiency, service levels, passenger satisfaction and other indicators, this paper evaluated the operation of Beijing BRT lines and contrasted the regular bus lines with a comparative analysis. A comprehensive summary of Beijing BRT operating experience was concluded. In general, BRT has the merits of running faster, saving travel time, reducing delay, high rate of punctuality, high efficiency, and being environmental friendly and so on. The survey also found that because there are differences in signal priority and line location in the three BRT lines, the running speed, operation time composition, passenger volume, loading ration, passenger satisfaction are different. To solve the BRT existing problems, BRT lines and the regular bus lines must be integrated into the same corridor, with the implementation of adjustment line’s location, transfer connections, and setting signal priority. This paper will be useful for Beijing BRT development and provides BRT experience for other cities.

In order to determine a reasonable length for left-turn lanes, the authors observed vehicles’ speeds on a selected left-turn lane set up with a new concept on a second-class highway and obtained speed data of a normal section, main lane taper start point and split point. Then, we analyzed the data by means of descriptive statistics analysis, the paired-samples T test and ANOVA. The results showed that the length of a left-turn lane could be shorter without compromising comfort and safety. The speed used to determine the length of main lane taper could be reduced by 5%, and the speed used to determine the deceleration length could be reduced by 15%.

To ascertain the cognition pattern of novice driver, indoor tests were designed in this study. Subjects' reaction time during ongoing test was recorded. By using H6 Head Mounted Optics eye tracking system, subjects' eye movement data was recorded; at the same time, subjects' electroencephalogram (EEG) was recorded by BioGraph Infiniti physical feedback system. With the field data, this paper analyzed the correlation between subjects' average reaction time and the strokes of Chinese character (Ns), average reaction time and the total number of information on the sign (Nt) both during placename searching and placenames reading assignments. This paper also analyzed subjects' visual pattern including average fix duration∖average fixation points∖average pupil diameter. And EEG%', an evolved parameter of subjects' EEG was chose to analyze the correlation between EEG and the information quantity of signs. This paper suggests further consideration of novice drivers' cognition pattern with the analysis results especially when making the standard of legibility distance and legibility time of guide sign.

With the development of expressway construction in China, designers and scholars in road traffic field gradual wake up that the essential purpose of expressway design should be ensuring drivers' safety. By analysis and driving tests, the research obtained the correlative model among augmentation of heart rate, radius of curve, operation speed and acceleration, and quantificational identified every index of expressway alignment meeting with mentality of drivers.

With the rapid development of highway construction in China, the importance of slope greening design is gradually increasing. This paper applied Analytic Hierarchy Process (AHP) into the design of slope greening and respective analyzed the weight of engineering effect, investment, ecologic function, aesthetics, visual safety for drivers and cultural connotation for a slope greening design. Through the analysis, this paper discussed the methods and principle for slope greening design using AHP. Finally, the paper obtained the result that the effectiveness and the reliability of engineering technology environments are the most key considered factors for slope greening design and also consider the act of protecting original ecological environment, hindering the noise and beautifying the environment for a slope greening design. The method and principle in this paper can provide theoretical method for slope greening design.

6 STUDY ON MULTI-STAGE DECISION EVALUATION METHOD OF INFRASTRUCTURE CONSTRUCTION PROJECTS WANG Fang HOU Yu (School of Management, Wuhan University of Science & Technology, Wuhan, China, 430081) Abstract: Infrastructure constructions are hardware conditions for national and regional economic development. Due to the characteristics of long life cycle, high capital investment, complicated investment relations and flexible multi-stage decision, it is very difficult to evaluate the project of infrastructure construction. The reasonable and effective evaluation method is the key factor to affect the speed of investment recovery and infrastructure construction in the situation of resources and funds shortage. The multi-stage decision evaluation method is proposed based on the evaluation methods of net present value and real option, after transformation from the phase changes in the variables to the phase changes in the parameters by Ito random theorem. This method can satisfy the evaluation requirements of multi-stage decision project because the mutation factors of evaluated variables are considered, and the continuous assumption of valuation variables is removed.