Research conclusions: The real train dynamic test indicates that the average dynamic deformation and dynamic stress of the subgrade are close to that of passing current trains when passing freight trains at speed of 120 km/h, and the average dynamic stress of the subgrade is the 1/2 of passing current trains and the average dynamic deformation of the subgrade is the 1/3 of passing current trains when passing 200 km/h EMU. Based on a comprehensive analysis of the test results, this paper points out the main controlled elements of speed-increase subgrade, and presents the technical condition of speed-increase subgrade and the problems and vulnerabilities existed in speed-increase subgrade of existing railway.

Research conclusions: The improved sandstone is much better in property of physical mechanics, especially in mechanics strength and hydrological property, which can satisfy the requirements of railway subgrade for filling materials, so it is feasible to use calcined lime as the modified agent for all weathered and serious weathered sandstone.

Research conclusions: On the one hand, the improved slide bar can consistently and reliably pressure the inner side of stock rail to keep the consistent pressure. On the other hand, it can be easily and flexibly adaptable to gauge adjustment of stock rail. In addition, the slide bar can reduce the switching resistance of turnout and insufficient displacement of switch rail to guarantee the reliable switching of turnout, which meets the requirement of railway for slide bar.

Research conclusions: The system function is the most important to ballastlesa track. But different structure models and components need different ways for realization of functions. To establish the theoretical system for ballastless track based on system function design is helpful for making the analysis of how to serve the function with structure, define the requirement of each component for function, seek the problems in structure system and establish scientific analysis methods.

Research results: It is similar in concrete design strength between BS5400 and Chinese Highway Code and after being divided by 1.1, the value of reinforced characteristic strength in the Chinese Highway Code is similar to that in BS5400. In reinforced concrete design, the calculated result as BS5400 is Mu=5266 kN·m, the calculated result as Chinese Highway Code is Mu=4630 kN·m, these calculated results are the basically same. Chinese Highway Code is safer than others. On short columns design, it focuses on safety in Chinese highway codes; while for BS5400, more consideration is given for economical result. On considerations affecting design details, the mini Mum areas of reinforcement in members in Chinese Highway Code is Much less than BS5400.

Research Conclusions: There are large risks in reconstruction of the foundation of existing line and the second line, in jacking-in engineering and in pipe engineering, so it is necessary to pay more attention to these risks in the constructions, and for keeping these risks away to guarantee the traffic and construction safety, the key processes should be controlled, the reliable, effective and mature construction technology and methods should be adopted and construction organization should be done well.

Research results: The speck analytical and controlling method for flexibility and configuration control and stress measurement in beam with cantilever wall basket constructing method has been presented. The results show that the flexibility and configuration of the bridge adequately confirm with requirements of design and bridge construction codes.

Research conclusions: The sectional size and burying depth of tunnel are not the causes for deformation intrusion structure ambit, the main causes for it, unfavorable geological conditions, excavation method, auxiliary construction method, primary lining on time and feedback of information on measured data. The study shows: (1) For single track tunnel, the short benched method should be adopted with length of 10~15 meters and for double track tunnel, CRD or CD method should be adopted, or through the leading grouting and big steel tube support in advance, the short benched method should be adopted. (2) The obligate distortion amount of 5~10 cm should remain in advance to single track tunnel of the IV level rock, 10~15 cm to two track tunnel, 10~15 cm to single track tunnel of the j1 level rock, 15-20 cm to two track tunnel and 30~40 cm to tall terra stressed tunnel. (3) If the deformation speed rate is more than or equal to 5mm per day and the total accumulative deformation amount is more than or equal one-third of the obligate distortion amount, the primary lining should be reinforced, and if speed rate is more than or equal l0mm per day and the total accumulative deformation amount is more than or equal to one-third of the obligate distortion amount, the working face should be closed, supported and reinforced with radial grouting. (4) For soft rock and tall terra stressed tunnel, the integrated techniques of primary support and release and reinforcement and lining should be adopted. (5) For intrude structure ambit of the tunnel, first grouting can be conducted to the intrude structure ambit and then the steel frame should be exchanged.

Research conclusions: The main causes for the landslide are decrease of the antiskid capacity of slides zone under the action of water, manual excavation of the tunnel open or blasting. The landslide can be controlled effectively by taking relative measures, such as surface drainage, jetting concrete, construction of gravity retaining wall before the tunnel excavation, adopting pipe-shed grouting in advance, steel structure, grouting anchored bar, consolidation grouting and lining.

Research results: Through doing research on control technology for deformation of the ridge section of Wushaoling tunnel, the relative measures can be taken for successful control of the tunnel deformation in construction, including choice of reasonable dross section shape, remaining deformation amount for the tunnel in advance, multi-supporting, enhancing the rigidity of the flexible lining structure and adopting short benched method with rapid excavation, rapid supporting and timely lining.

Research conclusions: For rapid construction of the tunnel under condition of highland stressed weak wall rock, first, there should be a support with enough strength to resist the deformation of wall rock and the wall rock should be closed on time with suitable method to form a closed support ring to set performance of the support; then the construction machinery is matched according to the construction method and conditions.

Research results: The basic grades of surrounding rock under high water pressures can be modified by adopting [Q]=[BQ] Jw(Jw=0.1~0.05). Serious grade differences may occur near the standard values in the determination of the grades of the ground stresses on the basis of TB method. Doing researches on the in-situ ground stress assessment and in-situ acquisition technology are an effective means for the modification of the ground stress in the grade determination of the surrounding rock in the construction.

Research conclusions: For prevention of and avoiding high constructional risk in construction of high risky tunnel, the geological risky grade should be classified, the geological forecast in advance, measurement and control of wall rock and measures for alarm of prevention of disaster should be conducted well, more attention should be paid to the construction organization in unfavorable geological zone and the suitable construction program and measures should be adopted and taken, including reinforcement, excavation, support and lining of the wall rock in advance.

Research results: Results show that by the hybrid method of the absorbing boundary and the nonreflecting boundary, the boundary reflection may be absorbed completely, and by the staggered-grid high-order difference method, the simulated result is very efficiently and precisely. The snap shots of wave-filed and its characters of seismic wave propagation for the complex heterogeneous media, karat cave, and weak interlayer are very directly and exactly.

Research Conclusions: The current velocity and the vortex frequency influence the support system length mostly. The unstable criterion of the support of the high order for submerged floating tunnel is larger than that for low one. The Melnikov method can be used for judging whether the allocation of support system is reasonable or not.

Research results: With continuous development of railway and continuous increasing speed of train, the computing program with define-element analysis to create optimized computing input and output interface can improve the design efficiency, accuracy and quality of catenary of electrified railway.

Research results: Application of equivalent tension not only reduces the tension of catenary, but also enhances its speed and improves construction security. And the requirement of installing catenary in place for one time can be met by this method.

Research conclusions: Compared with other damping mode, floating slab damping roadbed with steel spring has the advantages of perfect damping effect and less maintenance, and its disadvantage of long construction time can be overcome with scientific arranging the construction procedure, so it can play more important role in construction of urban mass transit.

Research conclusions: The gapless and polymer housing zinc-oxide surge arrester with disconnector integrates arrester, isolated device and disconnector together with the features of rational design, fresh structure, characteristics stability, good applicability and perfect operational effect. It is advanced in isolated structure and disconnector and its key property indexes can meet the requirement of metro for lightning protection, so it can be widely used in urban mass transit and intercity railway with DC1500 voltage.

Research conclusions: (1) The current African highway is at low level which becomes an important element of restraining the economic development. (2) The African highway construction market is a considerable market and it is feasible for Chinese enterprise to open this market. (3) It is necessary for Chinese enterprise to adopt BOT or PPP mode for opening this market and the better preparation works against the unfavorable elements should be done.

Research conclusions: The "Market Pricing System" is adopted in Japanese engineering accumulative computing system which is very close to our highway engineering pricing management system, so our reform of highway engineering pricing management can draw following inspirations from it: The "Three exceeding" phenomena should be eliminated, the effects of quota should be paid more attention to, the valuation method of separating estimating price with pricing should be adopter and the intermediary organization should be independent.