Research conclusions：There are three schemes of leading Shanghai-Kunming Passenger Dedicated Line into Changsha hub, namely, one is north-inbound and south-outbound from Changsha South Railway Station, the other one is to build new stations in Changsha, Zhuzhou and Xiangtan, and the last one is south-inbound and north-outbound from Zhuzhou West Railway Station. This paper analyzes the three schemes from the aspects of the construction cost, passenger traffic effect, coordination with the city plan and reasonable use of remained project with fuzzy analytic hierarchy process. Finally the first scheme is determined, which not only meets the urban development planning and railway transport demands, saves the construction investment, reasonably use the remained projects, but also ensures successful starting construction of Hangzhou-Changsha Passenger Dedicated Line.

Research conclusions：(1) The scheme of leading the line in Fuxin Region should be consistent with urban planning arrangement, and fully considers the development level of the local economy and the reasonable balance between demolition and line direction. (2) The track should be short and straight as much as possible and keeps away from unfavorable geological area to enhance the safety of construction and the reliability of line operation. (3) The choice of the track technical standard should be combined with station operating conditions , the track technical standard should be determined reasonably in acco rdance with the v-s curve and the technical and economical values should be reflected in the engineering design.

Research conclusions：Selection of the station site of passenger dedicated line is constrained by many factors, such as the city planning, unfavorable geology and sensitive area in environment and it is essential to realization of the main functions of the passenger dedicated line, making residents convenient for trave and getting good social and economic benefits. The station site should be selected on consideration of putting man first, the railway network arrangement, the city planning and sensitive area in environment for reducing interference to the existing facilities and selecting the optimal station site so as to achieve that the comprehensive investment is the smallest in main railway construction and urban matching construction and the optimal social and economic benefits are obtained.

Research conclusions：The researches and tests on Mianyang-Chengdu-Leshan Railway, Lanzhou-Chongqing Railway, Chengdu-Lanzhou Railway and so on prove that IKONOS Satellite images with resolution of 1.0 meter can basically meet the topographic mapping requirement of a scale of 1∶2 000. IRS-P5 Satellite images with resolution of 2.5-meter can meet the topographic mapping accuracy requirements of a scale of 1∶10 000. Satellite images with resolutions from 0.6 to 1.0 meter and 2.5-meter can respectively meet the plane requirements of topographic map revision for a scale of 1∶2 000 and 1∶10 000.

Research conclusions：The seismic reflection was successfully used for the exploration of coalmine gob in the area with complicated geological terrain condition and in loess area in Linxian along Taiyuan-Zhongwei-Yinchuan Railway Line. During the investigation along the natural ditch, the natural superficial bedrock was used to reach the goal of "dwelling on the solid body and avoiding empty body", and in a specific area, the congested cannon and turnaround cannon were used for increasing the superposed times. For treatment of bend line of seismic reflection, the reasonable selection of CDP range of the plane of common reflection could improve the treatment accuracy remarkably and determine the boundary of coal gob accurately, which could provide the powerful basis for the railway route selection.

Research conclusions：In the current code, the characteristic sampling value o f subgrade's bearing capacity is determined according to the relative deformation in plate load tes, tresulting in making no full use of the bearing capacity of soil foundation. In order to make full use of the foundations' bearing capacity, the characteristic sampling value of foundation's bearing capacity should be determined according to the various allowable settlement standards for the different projects in the design of railway engineering. Under the premise of meeting the deformation requirements, the characteristic sampling value of foundations' bearing capacity should be appropriately expanded in order to achieve the harmony and unity between the strength and deformation. The conclusions presented in this paper can be as reference to similar railway engineering.

Research conclusions：With the measured values, the model is verified. The simulation results of subsidence center and settlement value are basically consistent with the real measured results. The model is applied to predict the ground subsidence with the different schemes of pumping up the underground water. The predicted results show that proper pumping up the groundwater can reduce the regional ground subsidence volume, the subsidence gradient and the unevenness of the ground subsidence.

Research conclusions：From the research on the sensitivity of such new composite foundation to the all parameters, it is concluded the effective range of the negative friction of rammer carrier CFG pile is wider than the common CFG pile , and the neutral point is very low or zero. The effect of pile body of rammer carrier CFG pile is more obvious and the cushion of rammer carrier CFG pile composite foundation should be thicker than common CFG pile composite foundation.

Research conclusions：China's railway track design standards are relatively higher than the German's standards and the selection range of the railway track design parameters is wider. These show China railway is good in the travel comfortableness and has the room of the further development. It is in line with the direction of development. However, some design parameters need to be optimized by doing experiment.

Research conclusions：The scheme of using inverted T type end-spine, filling certain depth of roadbed surface and bottom layer under small end-spine with graded gravel-doped cement, and filling subgrade with graded gravel-doped cement at both ends of large end-spine within 5m width by 1∶2 slope was adopted. Adopting this scheme, the maximum longitudinal displacement of end-spine is 3mm under loading, which can ensure the safety and stability of track structure. Besides, the costs of the friction plate and end-spine are lower than that for Beijing-Tianjin intercity Railway.

Research conclusions：The results show that bridge load has little effect on the stress of rock mass of slope, and the slope displacement is very small. The plastic failure zone mainly occurred at a small area of basal slope of left bank, and there was no plastic failure zone in other places. The safety factor of the left and the right banks of the high-steep slope under bridge load is 1.85 and 2.20 separately, and the high-steep slope of the bridge is entirely steady at present.

Research conclusions：The mechanical behavior of rock mass of high-steep slope under bridge load obtained by 2D analysis is the approximately same as that by 3D analysis. The values of stress and displacement obtained by 2D analysis are generally bigger than that by 3D, especially this phenomenon is obvious near the bridge foundation. Compared with 3D analysis, 2D results of slope stability is relatively conservative under the same condition. The error between 2D and 3D is not constant and it changes with the changes of load intensity, bridge foundation position, gradient, bridge foundation size etc.

Research conclusions：With the renewal of the concept on civil engineering design, the technician should pay more attention to the bridge structure design for disaster prevention and reduction of bridge. It is necessary to make the ductility design for earthquake resistance to complicated bridges. Through seismic analysis of large span continuous rigid frame bridge in intense earthquake area under rarely strong earthquake, this paper offers an effective ductility design method. Namely, using non-linear temporal analysis method gains the force and displacement of the piers, and comparing the response results with the yield-resistant capacity of each pier gained through Pushover analysis determines whether the bridge has enough ductile earthquake-resistant capacity or not.

Research conclusions：Through the repeatedly studies and tests in constructions of the pile foundations of Jinjingba Bridge and Xitanjie Bridge of Dali-Lijiang Railway in Yunnan Province by China Railway Eryuan Engineering Group Co. Ltd and China Railway 8th Bureau Group Co. Ltd, this paper offers the mud-jack with grouting tube and boring protected wall method and the bored grouting method used for the construction of the pile foundation in karst area. Application of these methods can solve the problems mentioned above in construction of pile foundation in karst area.

Research conclusions：(1) The gas overflow in the Caishenmiao Tunnel was accidental phenomena and gas in the surrounding rock was not in adsorbed state, but in free state, with very low gas content, no pressure, small natural flow of gas and fast attenuation. So the construction area was in low gas area. (2) As the natural and geological environments were complicated, the gas not only overflowed from the gas-bearing stratum, but also probably overflowed from the other stratum occasionally. (3) The gas overflow should be dealt with carefully. It should be known clearly that the hazard of such gaswas small and the gas hazard could be neglected aswell. The some measures should be taken so as to avoid the gas hazard.

Research conclusions：(1) By comparing the power grades between wind power installation and the fan for underground engineering, it is found utilization of wind power installation instead of electric driven fan can realize the active utilization of wind energy of ventilation for underground engineering. (2) The analysis shows the structure of vertical-ax is wind power installation is more suitable for connection with the axial flow fan for underg round engineering. (3) The methods formatching rotational speed and power between the fan and wind power installation are put forward and they are verified by the example.

Research conclusions：Through the plane design and optimization made to the shared site of three tracks in the Chuanyanghe Vehicle Base composed of the northern stabling yard of Line 11, southern periodic repair depot for Line 11 and stabling yard of Line 13, the integration of urban plan is improved, the strong points of resource sharing of urban mass transit network and vehicle base are given play to and the construction cost, the floor area of the depot and operation cost are reduced.

Research conclusions：The adaptability of remained condition for PSD installation in civil engineering to the unknown sizes of vehicle before construction should be fully considered. PSD can be positioned by the continuous groove remained on platform and continuous steel I-Beam remained on the top for PSD installation. The construction error exists objectively, therefore, on one hand, the construction accuracy must be improved, on the other hand, some remedial measures should be taken so as to meet the PSD installation requirement.

Research conclusions：The additional stresses distribution of existing tunnel was of laterally symmetrical status which took the central line of new tunnel as symmetry axis in construction process. The subsidence of the existing tunnel occurred and additional stresses of existing tunnel increased during construction of new tunnel. As the maximum internal force in the target face of the tunnel tubular lining appeared on the tubular lining on the arch web on both sides of new tunnel, the stratum between tunnels should be reinforced. When construction was finished, the main stress in the target face of the tubular lining of the shield tunnel became the biggest.

Research conclusions：The research results show that the reasonable choice of track structure and structural parameters are the main measures for reducing the vibration and noise, the stiffness design of the track structure is the focal point of track design, and research and development of vibration and noise reducing track structure is the development direction in future.

Research conclusions：When leading newly built rapid-speed railway into the district station under construction, the technical standards of the track under construction, construction situation and operational demands of the station under construction should be well known. The waste engineering and design changes should be minimized. When the district station links with the lines of more than one direction, the station layout should be made in yards according to the line priority. If the cross-line traffic is needed in all directions, it is necessary to build the connecting line. Double-line condition should be reserved if the line under construction is a single-line railway.

Research conclusions：The main reduction functions of variance of the main soil layers are obtained with systematic random field method. The average value and variance of compression modulus, bearing capacity and shear strength index are obtained with statistics. The reduction function of variance is used to modify the variance.

Research conclusions：It is critical to determine the reasonable center of form in rigid calculation. The pile should be arranged according to the reasonable coincidence of the center of form of reaction force and the center of form of pile foundation. The bore force situation of the pile foundation should be calculated under different load combinations. If the center of form of reaction force can not coincide with the center of form of pile foundation, the bearing capacity of the pile foundation should be calculated according to the eccentric load. The reinforcement pile cap's stiffness, soil constraint and torsion moment should be considered in flexible calculation. The vertical and horizontal bore force situation, moment of piles and foundation displacement obtained with finite element method can be compared with those by rigid calculation, which can provide the data for crack calculation and upper frame structure of pile.

Research conclusions：Design and construction of New Guangzhou Railway Station involved many specialized subjects. The code for railway bridge was adopted to the bridge design and the code for building construction was adopted to the waiting hall on the top and canopy. As the bridge and the upper building jointly bore the load and deform coordinately, it was necessary to do calculation for them as a whole. As the structure was good at bearing load as a whole, the whole building had a good earthquake-resistant capacity and dynamic capacity. As the nodes of New Guangzhou Railway Station were very complex, the adequate measures were taken for the partial structure. In addition, as the construction of bridge, waiting hall, canopy and subway were conducted across, a reasonable construction plan was needed.