Research conclusions: The Shear Strength Reduction Method(SSRM)can be conducted to analyse the sand embankment slope stability reasonably.The shear strength parameters(mainly cohesive c ) matching relations between sand filling and clay soil layer will effect the slip surface behaviors directly. Some constructive advice, such as decreasing the side slope angle, enhance sand filling-clay soil layer interface construction treatment and embankment compaction, was drawn to increase the sand embankment slope stability in practice.

Research conclusions: The simulated results agreed with the measured results well. Vertical displacement for top surface and lateral displacement for panel are affected by rheology of reinforced structure. Stresses of reinforcement increased with time at the beginning, during a specified time the stresses in it decreased and the reinforcement showed the behavior of relaxation.

Research conclusions: Take the entity project of Wuhan-Guangzhou passenger dedicated line for example，a lot of indoor tests, such as triaxial tests, consolidation tests, expansion tests and contraction tests were carried out. The characteristics of red clay including stress-strain relationship, consolidation deformation behavior, and expansive- contractive deformation behavior were studied. The following characteristics of red clay were obtained: behavior of ultra- consolidation characteristic, behavior of consolidation but without compassion, consolidation and anti-profile characteristic, medium compression, relative less expansive deformation and more contractive deformation. In red clay areas, we could improve the particle size distribution of red clay to reduce its deformation; use heavy load to constrain its expansion. During construction, CFG piles could be used to strengthen the foundation and pile-plank wall，as well as bolts could be adopted to strengthen slopes. These are of great significance to the construction of entity project of passenger dedicated line and provide references for similar projects

Research conclusions: The paper proposes the method about the stability detection of Control Points m，which uses the information provided after the early CP Ⅲ plane and elevation control network adjustment and the measured distance and height difference of every two CP Ⅲ points calculated by measured data of free station in fine adjustment of ballastless track，and then compares with known distance and height difference. Theoretical analysis and testing results both validate that the method is correct and can detect the stability of CP Ⅲ points in plane and elevation. So the method proposed in the paper can be widely used in the project.

Research results: The results indicate that the crack initiate in the stress focus position , and the impact of main shear stress is very important. The growth of crack under static load is different from dynamic load condition. Under the same loading rate, the crack of PD3 rail is easier to initiate and grow than U71Mn's. To prevent and mitigate fatigue damage, suitable materials must be chosen based on the type of the rail line and work environment. PD3 rail steel would be used at heavy haul railway. U71 Mn rail steel would be used at high-speed railway.

Research conclusions: The ultimate tensile strength at room temperature of hot-rolled rails is 1 080 MPa, and hardness of tread is up to 300 HB. The H and O contents of finished rails are 0. 5 x 10-4% and 12. 3 x 10-4% respectively. The microstructure of tread and gauge comer is consist of pearlite and a little ferrite. The largest residual tensile stress in rails bottom is 200. 2MPa. The fracture toughness ( K1C) at -20℃is 32. 5 MPa?m1/2. When the stress intensity factor (?K) is 10 MPa?m1/2}and 13. 5 MPa?m1/2，the fatigue crack growth rate(da/dN ) is respectively 9. 55 m/Gc and 31.98 m/Gc. All results show that the 68kg/m hot-rolled rails satisfy requirements of”tentative technical specifications of 68kg/m rails"，and could be laid on heavy haul railway line.

Research conclusions: By the measure experiment on the spot to compare of impact force between wheel and rail and track structure vibrational acceleration, the results show that effect on impact force between wheel and rail is distinct by irregularity on rail welded joints. Especially when wavelength of the irregularity on track surface at the size is inconsistent , the effects on the P1and P2 are inconsistent as well as. At the same time，it shows that P2 can be reduced distinctly by the improvement of irregularity on rail welded joints,so that stress of track structure can be reduced.

Research results : The”High Trestle Bridge Gantry Crane Support Under Arch Method" is a safe，high efficient and non -polluted way for protective removing arch bridge in complicated construction environment requiring navigation under the span, high safety and short construction period. The control system for synchronous balance，multiple support and level restraint has been developed to guarantee the stability of the structure and pier, which forms a set of new technique for protective removing arch bridge.

Research results: The research on the bridge health monitoring and evaluation system is at the beginning stage and it has long way to go to put the system into practice. Nowadays only the response of low frequency can be measured precisely and only can reflect the entire status of the structure. However, even such response can be reflected in the entire status, but it is easily disturbed by the noise, error and unstable factors because the measured value is too small. The development trend of monitoring technology for bridge health is as follows; The first is to reduce the noise and unstable factors and the second is to enhance the sensitivity of diagnostic method of bridge damage to realize the quantization of the bridge damage through optimizing the technology.

Research Conclusions: Based upon Gray Theory and Analytic Hierarchy Process, a bridge is divided into three subsystems, namely superstructure, load-transmitted structure and substructure. According to the results measured from the bridge and the specialist's experience, quantitative values of indicating the health state for components can be conducted. The health state of each subsystem is assessed in accordance with that of the components. On the grounds of these, the health state of bridge structure can be produced.

Research conclusions: The successful construction of Wanzhou Yangtze River Bridge shows:(1)The closure scheme of no stress on closure rod with adjusting height differences between the front support point and the rear support point and making one steel truss displacement to eliminate the influence of rotary angle of cantiever is feasible.(2)The calculation and analysis of position change of closure point is the same important as the fine adjustment in the course of closure.(3)The installation order should be optimized in accordance with the actual conditions of each bridge. (4) Whether the technical measure of installing binder is taken or not will rely on the calculation and analysis made after the closure. ( 5 ) Lowering the height of temporary support to master piler is one of important measures for safety.

Research conclusions: The results show that the settlement and its area of the ground increase significantly due to the weight of structure, but the lateral movement of the ground reduces significantly due to the stiffness of structure; Vertical displacement of the structure is significantly influenced by tunneling, but the lateral deformation is not marked. The bending moment of middle beams change little, but the bending moment of side beams increase marked. The axial force of middle pillars decreases, but the axial force of side pillars increases. In practice, the side beams and side pillars should be measured.

Research conclusions: According to the tunnel's road net, resistance and recovery facilities' layout, traffic conation, ventilation system,this paper analyzes the fire probability in the different regions and the accepted extent of loss and absorbs the concept of performance fire control design. The transverse ventilation was adopted in the important fire resistance position and the comprehensive discharge fume scheme on the base of longitudinal ventilation in the general position. The resistance and discharge fume theory of civil architecture was taken in the tunnel's resistance and discharge fume design, and the tunnel's resistance and discharge fume theory was perfected. By analyzing the service tunnel, air flow and personal dispersal, the service tunnel's positive pressure design was cancelled to make the tunnel's resistance and discharge fume scheme on economic technique more proper and feasible.

Research conclusions：To the high pressure and enriched water fault F1，the construction method of geological forecast in advance, grouting consolidation, pipe-shed support and strengthening the structure is feasible. To the main fault, the grouting purdah thickness is 8 meters besides the tunnel contour line and to the fault influence zone, if the water pressure exceeds 1. 5 MPa and the water quantity exceeds 40 m3 per hour, the grouting purdah thickness is 8 meters besides the tunnel contour line. To the other cases, it is necessary to optimize the grouting purdah thickness and construction program，reasonably equip the construction machinery and strengthen construction organization and management for enhancing the production grouting capacity to curtain grouting per cycle/32 days and the process of boring-grouting-excavation" 22 meters per month.

Research conclusions: The research obtained that water outburst is a main engineering factor caused by soil and water losses. From current design and construction technique, this paper analyses key links and the difficulties in tunnel construction. As a result, this paper holds that advance geological exploring and hydrologic monitoring are basis of the making plan of water outburst treatment. A pre-grouting comprehensive measure that reducing water pressure upon lining is put forward，the drainage mess and drainage time length are controlled with an allowed value of water inflow and at the given period. These research results have been applied to an engineering practice of water outburst treatment in mountain tunnel of Karst zone, and it has obtained good results.

Research conclusions: Based on the characters of shale(T3sn)，a lot of construction countermeasures are adopted, including adjustment tunnel profile, accretion premeditate distortion, three-sidestep-diging into, setting steel structure, adjustment length of anchor-pole, strengthening inspection and so on. As a result of above measures, initial stage shoring distortion of tunnel is restrained effectively.

Research conclusions: When open excavation construction is carried out in deep excavation of city subway transfer station under complex environment, in-situ monitoring is a useful measure for safety guarantee to information construction. For subway station with complicated shape, compound maintenance forms that it includes retaining pile, steel support and anchor cable should be adopted to be as supporting structure of deep excavation. Stratified excavation method of earthwork and applying prestress to steel support are the important measure of reducing spatial effect and guarantee safe construction. FLAC numerical simulation is important means for the study of deep excavation deformation law.

Research conclusions: Through making analysis of the cause for light pollution of the glass curtain wall of railway station to the surrounding buildings, the discussion is made on light pollution harm to human body and the proposal is made that the light reflection pollution from the glass curtain wall of railway station can be eliminated or reduced by adopting special glass, non-curved-face curtain wall, glass lamina and special structure of glass curtain wall to make railway station becoming more comfortable for using.

Research conclusions: By discussing the concept, characteristics, operation procedure and feasibility analysis of PPP financing pattern, this paper puts forward the necessity of selecting PPP financing pattern in railway construction, also points out PPP financing pattern involved in railway construction is more easily to activate the private capital and foreign capital, and it is propitious to introduce the advanced technology and management experience. It provides reference for solving the financing problems in railway construction project of China.

Research conclusions ：(1)The result indicates that the risks of working drawing design, piling cut and pre-jack are greater than the ones of construction conditions and others.(2)The method of De1Phi uniting AHP could get the half-quantity result, which could meet the requests of”Interim Rules of Risk Evaluating and Management on Railway Tunnels" and "Guideline of Risk Management for Construction of Subway and Underground Works".( 3 ) 1'he method of De1Phi uniting AHP holds true for risk evaluating of simple works and risk identity of complex projects.

Research conclusions: Introducing board system is a very important innovative work for the enterprise directly under central authority, but the board system is not perfect. The primary goal and basic task of establishing the board system are to overcome the problem of”control of inner employees"，but establishing the board system needs certain conditions and environment. The enterprise directly under central authority should have special purpose and not give a show when establishing the board system. In the cause of establishing the board system , the more attention should be paid to the natural defects and disadvantages of the independent board system and relative adjustments should be made in accordance with the real conditions.

Research Conclusions: The full scope can be given to the construction project risk management by introducing the general control mode into the existing construction project risk management mode. In this paper, the analyses of the adaptability of the construction project risk management in general control mode and its effects are made

Research Conclusions ： Construction enterprise should change the materials management mode from decentralization into regional centralization by integrating the human resources, assets resources and information resources and establishing centralized management platform and reasonable regional network. In this way, construction enterprise can realize the integrations of standard，information and purchase and effectively control the materials to reduce the materials cost and enhance the benefits.