Research conclusions：conclusions：(1)From the views of meeting the traffic demands of outgoing and incoming of the Shanhai Pass and optimizing the railway network structure，the railway construction should be complete by 2020 in order to relax the traffic pressure and improve the service quality of the passenger outgoing and incoming of the Shanhai Pass．(2)From the views of promoting the coordinated development of the regional economy and improving the construction environment，the railway construction can change the poor transport situations of Chengde，Chaoyang and Fuxin areas along the railway，develop and enrich the travel resources and maintain the closely economic exchange of Beijing and Shenyang with the surrounding areas，and it is crucial to promotion of the coordinated development of the regional economy．(3)From the view of the projectg economic benefits，the two rapid passenger corridors with large traffic capacity will be formed after building the railway and they can enhance the railway network flexibility because they have enough traffic capacity in the early days after railway building．The trains of the different grades can run to meet the demands of the different passengers to reflect the public welfare and basic features of the railway．(4)The research on the method for the timing of building the railway presented in this paper is available for planing and construction of the transportation infrastructure．

Research conclusions： (1)Through the comparison and analysis of the local economic developments，transportation development and railway transportation before and after railway construction，the Chongqing—Huaihua Railway in general has met the requirement of the local social and economic developments and building the railway is a wise decision-making.(2)From the antecedent view，the Chongqing—Huaihua Railway was not built on full consideration of the traffic demand．It would be more reasonable to build the railway in the earlier five years．From the advanced view，the more social resources would be saved if double line was built for one time．(3)After opening to traffic for two years，lots of defaults are exposed，such as being insufficient of equipments and carrying capacity，passenger station faraway from towns and the not closely matching with the local planning．All these indicate that the concept of”Putting people first”was not implemented fully in the design，and the demands of the convenience，durableness and perfection are not met while the basic transport requirement are satisfied．(4)The advanced thought and foresight are needed to the railway construction on consideration of the local macro development trend and this is experience of the long - term traffic developments at home and abroad．Only in this way，can the railway construction well adapt to the local economic development．

Research conclusions：In analysis of linear elastic structures，the final result can be obtain by superposition of the static response and dynamic response．Whereas for the nonlinear structures，with superposition，the truth can not be got．The stress——inputting method and slow dynamic method presented in this paper are feasible and applicable for dynamic response analysis of structures affected by constant loads．With the former．the dead loads and dynamic 10ads shall be put together in the steady—state analysis and transient analysis respectively．With the later，the both loads will be put together in the transient stage．The two methods can be applied in both linear elastic dynamic analysis and nonlinear dynamic analyses．

Research conclusions：1) When the cutting soil layer is rather thick，the retaining engineering should be done first in the construction process and the monitoring of the slope on the both sides should be strengthened. ( 2 ) In the thick red soil layer area, the necessary retaining measures should be taken to the soil cutting or half soil and half rocky cutting with abundant groundwater. (3) When the parent rocks is possible to produce the dilatability argillaceous rock in the thick soil area, three indexes of the expansive soil should be distinguished to determines the soil nature for providing the reliable basis for the design and construction. (4) For high slope and deep cutting surveys, the exploration points should be rationally arranged according to concrete topographical conditions and the control sections should be properly arranged. In addition, the transverse width of the survey should be increased. ( 5 ) The result can be widely applied in the survey and construction of high slope and deep road bed of railway and highway．

Research conclusions：As the slope stability analysis is a comprehensive work, first the analogy method should be used to make qualitative analysis of slope stability based on the previous experience of the similar projects and then the limit equilibrium method should be used to make the quantitative analysis of the slope stability，and the model should be built to make simulation analysis if necessary. Finally the numerical simulation should be done with the finite element analysis software to find the weaknesses of the slope stress state so that the corresponding preventive measures can be taken with relatively low cost. The results of this study can be applied in the analysis and design of slope，particularly suitable for the alignment of the mountain railway and highway and slope design, and can effectively improve the efficiency and accuracy.

Research conclusions：(1) For the unit soil of the dam foundation s middle axle or the toe, when the effective stress method is used，the increase of the shear strength of the large main stress acting face is bigger than that of the shearing damaged face，and the increase of the shear strength obtained by using the specification method is between the above values. (2) For soil - stone dam built on the soft soil foundation, the increase of the unit soil of the dam foundations middle axle becomes less with the increase of the depth after its consolidating for a period of time while in the unit soil of the toe，this kind of becoming less trend is not obvious. ( 3 ) This research result is available for researching the increasing regulation of the shear strength in the drainage consolidation.

Research conclusions：(1) The frame - type pile plate wall is connected as a whole through its transverse supports to form a frame - type integral spacial structure. (2) The frame 一 type pile plate wall has the features of the evenly loading bearing, entirely coordinated deformation and high stability. So it can reach at the height that the conventional retaining structure can not reach at, with less impact on the surrounding building so that the land acquisition and demolition works can be much reduced. (3) Compared with the conventional retaining structure, the frame - type pile plate wall can play a big role in ensuring the stability of the deep cutting under complex environment and restricting the level shift of the soil on the both sides of the cutting and raising movement of the cutting foundation so that the landslide and unstability of the cutting can be effectively prevented and the stability of the whole cutting structure can be guaranteed. (4) This research result is available for the cutting project that needs high retaining and for constructions of railway and highway in the city proper with complex environment and in the narrow space，and it has the reference and applicable meanings for planing and construction of the similar railways.

Research conclusions：(1) Compared with the standard code for the ballastless track of high - speed railway in China， the thicknesses of the bedding surface and bottom of the railways built with the UIC and the French high - speed railway code are thinner, but the compactness is over high. (2) When the QS2 or QS3 grade filling material is used, it can meet the requirement of the Chinas high - speed railway standard，but when the Qsl grade filling material is used, it can not meet the the Chinese standard unless the material is improved- (3) For the treatment of the transition section, the requirement of the Chinese standard is low, but it can be reinforced by enhancing the stiffness of some parts of the bedding. (4) The settlement control standard for the subgrade designed and built with the French experience is more concrete and more strict than the UIC and is the basically same as the Chinese standard. The gap between the France and China can be filled by prolonging the resting time of the embankment or by over filling and compressing.(5) According to the above comparison and the surveys results of the subgrade bedding，subgrade，foundation and transition section, the areas that do not meet the laying requirement can be reinforced by taking measures of refilling, strong compacting，grouting and using the CFG pile and pile - slab structure，and those that meet the laying requirement can be directly used. (6) This research result can provide the reference to laying the ballastless track on the existing subgrade built with the UIC and the French standard and laying the ballastless track on the existing subgrade in China.

Research conclusions：(1) The method of force - centering occupied station on CPIV for the static inspection of track geometry of ballastless slab has the merits of the short setting time and high efficiency. (2) By using the high precision between adjacent points, this method can ensure the high regularity of the track，and the experiments on site prove the measured results are correct and reliable, satisfying the code requirement. (3) The application of the CPIV network for track geometry can unify the control references for the track slab and track fine adjustment, getting better regularity indexes and being worthy of wide application. (4) The research achievement can be applied in the static inspection of track geometry on the stages of construction and operation maintenance，and has the reference value for the code compilation and improvement．

Research conclusions：(1) Using the deck type steel braced arch at the No, 8 bridge site(416m) of the Hutaioxia Jinsha River Bridge is the best engineering plan. Using the steel truss suspension bridge at No. 27 bridge site (98 + 660 + 98 m) can remain the condition for the hydroelectric plan of river and can get the better economic and social benefits. The deck type steel braced arch has features of the good load bearing capacity, good rigidity and nice looking and is suitable for the high mountain and deep valley area，but it produces the impact on the water storage and shipping under bridge because the arch rib is installed on bottom of the structure. (3)The steel truss suspension bridge has the features of the fine anti - seismic performance and good rigidity to meet the train requirement. (4) The research result can provide the reference to the type selection of the large span railway bridge in mountain and deep valley area.

Research conclusions：(1 )The reaction force form of the foundation of the arch bottom of the tunnel is closely related to the displacement trend. When the arch bottom raises and deforms, the reacting force of the foundation is only composed of the counterforce，but when the arch bottom compressedly deforms，the reacting force is composed of the counterforce and the compression resistance of the foundation. (2 ) For the shield tunnel，the lining structure calculation model of reacting force on the arch bottom should be used and it can precisely reflect the load bearing characteristics and displacement trend，and overcome the security risk due to the insufficient safety factor. (3) The form of the reacting force on the arch bottom based on the displacement trend and the corresponding calculation model are put forward. (4) This research result can be applied in the shield tunneling project, mining project and open excavation subway station or subsurface excavation subway station.

Research conclusions：(1) When shallow tunnel under 一 passes seasonal river valley，the main risk comes from the huge ground water inflowing into the tunnel possibly to produce the water and mud bursting and the collapse of subsurface cut tunnel and make the tunnel lining structure floating. (2) The construction risk can be much cut and structure can be safe and reliable by adopting the door - type sealed structure system composed of the secant pile, top beam, anti 一floating board，grouting to the rock in the framework and fully sealed lining structure of tunnel. (3) The working order of sealing before excavation and the effective risk control plan can ensure the construction safety and control the construction risk. (4)This study result can provide the reference to the similar projects.

Research conclusions：(1) In the high filling region with deep topsoils, the “T - type” foundation would be adopted, with its flange to bear the vertical loads so that the foundation would not settle. It had less impact on the traffic safety because of the less excavation of the deep soft soil. (2) In the subgrade region with the filling thickness of less than 2. 0 meters, the shallow foundation with the expanded underside would be designed. After replacement of substrate material, some parts of the soft soil subgrade would be reinforced by filling the flagstones and compacted by filling the sandy and stony soils. When the bearing capacity of the foundation met the design requirement, the shallow foundation with the constructed so as to lower the requirement of the foundation for the bearing capacity of the undisturbed soil. (3) The shallow foundation with the expanded underside was proved safe and feasible by the field testing. The horizontal displacement of the foundation surface, the foundation torsional angel and the support deflection met the technical demands of the design. (4)This research result could provide the reference to the similar works.

Research conclusions：From the analysis of the line direction of the Chongqing - Guiyang Railway after it accessing into the Guiyang hub，it is concluded ： ( 1) The plan for the freight train of the Chongqing - Guiyang Railway accessing into the Guiyang hub should consider the demands of the upgrading of the existing railway line to reduce the abandon projects in long — term future. (2) The plan for the fright train accessing into the existing Sichuang - Guiyang Railway via connecting line can save the construction investment and has a good coordinations with the projects in the near future and long - term future. (3) This research can provide the reference to the similar works.

Research conclusions：From the research on the schemes of the station types of the Guiyang East Station，it is concluded the layout of distributed yards should be adopted when several lines accessing into，the layout of the yards for the different lines should be adopted when there is a little exchange trains among the lines and the layout of the yards for the different directions should be adopted when there are many exchange trains among the lines． The method for selection of the general station type presented in this paper can provide the reference to the similar works．

Research conclusions：(1 ) The construction of city regional rail transit should fully consider the current development situation and overall plan of the city and meet the traffic demand and development characteristics of city. (2) Based on the compreh ensive analysis and study on the compliance of the planning，the speed target value，the transfer mode， engineering economy, traction power system and signal system, the city regional rail transit plan and system can be determined. (3) The construction of Wenzhou regional rail transit is very crucial to building the development pattern of the " 1650" large city and improving the urban traffic system, and it can provide the reference to the similar works.

Research conclusions：(1) Construction of the intercity railways should fully considers the urban development features，the urban overall planning and the intercity railway network planning to meet the traffic demands among the cities. (2) The comprehensive analysis of the layouts of the tracks and network should be made according to traffic plannings between cities, such as the passenger flow distribution and the other transportation modes. (3) The radiate intercity railway network of "one loop and five axles" for the Wuhan city cycle，with the total railway length of over 1 000 km is presented in the research and it belongs to the moderate level of the developed city cycle in China. (4) The research result presented in this paper can provide the reference to the intercity railway development of the other cities and city.

Research conclusions ：(1) The establishment of the data bank for the standardization design should fully consider the characteristics of the all specialties and select the appropriate data bank structure. At the same time, the selection of the management platform of the data bank should meet the requirements of the large storage volume, rapid searching and common sharing, with the high security, high — efficiency and high reliability. (2)The server/client data bank system by using the SQL Server + Visual Studio can meet the requirements of the common sharing of data, reliable storage and backup, enhance the working efficiency and reduce the cost. (3)The application of the data bank system for standardization design of the rail transit can play a very important role in standardizing the rail transit design，accumulating the construction experience and developing the urban rail transit. This research can provide the reference to the similar works.

Research conclusions：(1)The interconnection and interoperability between the city regional railway and the national railway can be convenient for the through passenger flow between the city regional railway and the national railway，but the traction mode, power supply system，signaling system and gauge of the city regional railway must be compatible with those of the national railway. (2) After the EMUs run on the national railway，it will produce the big impact on the traffic capacity of the city regional railway, resulting in the unsmooth transport organization and operation management of the city regional railway. The construction investment will increase because the gauge of the city regional railway has to meet the requirements of the national railway. So the Line SI of the city regional railway should not be interconnected and interoperable with the national railway. (3)This paper provides the theoretical evidence for the construction of the regional railway and also provides the valuable reference to the study on the relation between urban rail transit and national railway.

Research conclusions ： (1) The characteristics of the dynamic response of underground structure was associated with the soil characteristics. The horizontal deformation of the underground structure was limited by the soil, with its movement with the soil and a little variation along the structure height. (2) The moment of the outside component was larger because of the direct contact with the soil. (3)The earthquake can increase the moment and the shearing force to the middle column significantly, so the column would be more easy to be damaged. (4)The results can provide reference to the seismic design of subway station or other underground structure.

Research conclusions ：(1) With the combination forecasting methods, the regression model for the price margin coefficient is built by using the curve fitting method and modified by using the residual series ARMA model and then the regression ARMA combination forecasting model is built to forecast the expected value of the price margin coefficient of railway project for effective control of the project investment. (2) The combination fitting model has good fittingness. By using this model, the material price margin coefficients from 2009 to 2011 were checked and the forecasting values were well fitting with the actual values. (3) The combination forecasting model presented in this paper is available for the investment estimate of the planned project, the investment evaluations of the medium and long term projects, the cost control of the undergoing project and the bidding price of contracting project.