Research conclusions: Based on studying the program of leading Shenyang － Dandong Passenger Dedicated Line into Shenyang terminal，the program of track joining in Dandong area，the program of the railway alignment along the Shiqiaozi development zone between Shenyang and Dandong，the program of the railway alignment along the existing Shengyang － Dandong Highway，the program of leading the railway between Benxi and Tongyuanpu into Benxi original station and the program of leading the railway into Benxi East via Wolong，the proposals were made that on the premise of fully considering the functions of passenger dedicated line，the passenger dedicated line should coordinate with the urban plans and should be led into the urban central area as much as possible to convenience passengers＇ entrainment and detrainment and enhance the railway service quality．

Research conclusions: The deep analyses of the alignment scheme features and research thoughts on leading Pucheng － Meizhou Railway into Wuyishan Region were made to determine a reasonable recommended scheme． The process analyses of the alignment schemes reflected the importance and influence of railway network，environmental protection， geology，planning and engineering quantity on choice of the alignment scheme．

Research conclusions: The construction of Wuhan － Guangzhou Passenger Dedicated Line，upgrading of Hunan － Guangxi Railway，construction of Hengyang － Chaling － Jian Railway，upgrading of Lei River Bridge and other construction projects in Henyang terminal have been completed successively，and the Huaihua － Shaoyang － Hengyang and Ankang － Zhangjiajie － Hengyang railways will be led into the Henyang terminal． As construction and upgrading periods were different，the construction and upgrading seriously interferred each other． Based on the analysis of the current situation of Hengyang terminal，and on consideration of the function orientation and construction schedule of the Hengyang － Chaling － Jian Railway，making full use of the completed project and avoiding waste，the study was done on the scheme of leading Huaihua － Shaoyang － Hengyang Railway into Henyang terminal via main track and the scheme of leading the railway into the Henyang terminal via the outside track． This paper compares these two schemes from the aspects of track length，construction cost and the railway operational situation． It was decided to adopt the first scheme．

Research conclusions: Recognizing and measuring the influence factors and using fuzzy comprehensive evaluation method to select the scheme for the actual engi neering have the important directive significance to the railway alignment． It can be seen from the actual engineering that the same evaluation factors will produce different results with the work going on and the influence factors being clear and meticulous． This method has been used for comparison and selection of two schemes for the railway，getting good result． This method also can be applied in comparison and selection of many schemes for the railway alignment．

Research conclusions: Through the studies on multi － source geological information integration， remote sensing information sampling，3D geography modeling and engineering geological evaluation method，the 3D visualization GIS integrated system was established to realize the functions of geological information management，spatial analysis， thematic mapping and 3D view，and improve the efficiency and reliability of railway geological alignment in mountain area．

Research conclusions: From the research it can be seen the conditions of black rock slope to generate weathering failure include development of joint fissure and existences of ground water flow and pyrite，and the acid water produced by the oxidation of pyrite is the major factor to cause the failure of the black rock slope． And this chemical effect can enlarge the pore space of the rock，lose and dissolve the material composition，and weaken the friction force between the particles on the rock surface． It is proposed the engineering measures of containing pyrite weathering and oxidation and the corruptive change of material composition should be taken for control of such type of slope．

Research conclusions: By comparing and selecting the optional schemes and following the principle of keeping the railway away from goaf and soft soil areas for the railway alignment in karst and soft soil areas，the track conditions were improved and the safety hidden danger was eliminated，obtaining good social and economic benefits．

Research conclusions: Pipe pile featured with the high strength， short construction period and easy control of construction quality can meet the high demand of construction of passenger dedicated line with less total settlement and less settlement velocity at the different phases compared with other reinforcement methods． In the soil foundation，under the action of horizontal force，pipe pile is in failure state due to the bending moments． The check calculation of the entire stability of the subgrade is made with the shear strength，resulting in high safety coefficient valuations． The load bearing modes of the pipe pile include the modes of pile － raft structure，pile － board structure and pile － net structure．It is proposed to strengthen control of the construction quality，to improve the strength of soil between piles and the pipe pile＇s top connections and to do the research on pile － beam structure．

Research conclusions: Considering the conditions of topography，geology，hydrogeology and other factors，the technical measures and suggestions are offered to subgrade waterproof and drainage engineering to ensure the structural strength and stability of the subgrade through doing the study on slope protection and waterproofing and drainage system for the subgrade of passenger dedicated line．

Research conclusions: The discussion and technical and economic comparison were made for three schemes of 20‰ gradient，25‰ gradient and 30‰ gradient in the Huoshan crossing section，and the simulations of acceleration and breaking performances of the 250 － 300 km / h EMU running on long slope were made． If the 30‰ gradient was used， the Huoshan long slope tunnel could be cancelled and the construction investment could be saved． So the 30‰ gradient was determined as the maximum gradient in some difficult sections of this railway．

Research conclusions: From the analysis it can be seen the most of the product standards are the basically same or equivalent，including the rail standard，fastening standard，sleeper standard and ballast standard，a few of the Chinese standards are higher than the French standards，including the precision of static laying ballast track and the precision of welding joint，and some standards are different in the content and system structure，including track bed standard，CWR standard，installation standard of rail expansion joint and track maintain standard．

Research conclusions: The finite element method was used to set up a longitudinal integration calculation model of rail －track slab － bridge － pier based on the longitudinal interaction mechanism of line － bridge － pier，and the corresponding general calculation program was compiled． With the program，the longitudinal stresses behaviour of the commonly － used 5 × 32 m simply － supported beam bridge and continuous bridge of passenger dedicated line were calculated，and the analyses of the parameter influence of the fastener longitudinal resistance，resin elastic modulus of the convex plate， friction coefficient of the bottom track slab and the temperature load value were made． The calculation results show ( 1) For the long grade slab track，the longitudinal relative displacements of rail － slab and slab － bridge should be limited within the range of 0． 2 mm and the corresponding resin elastic modulus of convex plate should be larger than 120 MPa． ( 2) The brake effect and longitudinal component force of live load should be applied to the bridge on long grade to make the computational check of convex plate． At the same time，the convex plate structure should be strengthened and the bonding strengths of convex plate，filling resin and track slab should be enhanced．

Research conclusions: The structure model established with the finite element software ANSYS was adopted to analyze the impact of the rail lateral force of heavy haul railway on the fastening stress，lateral deformation of rail head，rail base elevation and rail pad deformation，and the change regulations of deformation and stress of all track components were obtained． According to the simulation of track structure，when the lateral force on rail was bigger than 250 kN，the rail overturn possibly happed．

Research conclusions: For the design and construction of joint of reinforcement concrete steel tube column and reinforcement concrete beam － slab structure，a structural form called combination structure of steel ring plate －reinforcement concrete ring beam is presented． In which，the steel ring plate bears the shear force and reinforcement concrete ring beam bears the moment respectively． This kind of joint has the following advantages: clear load distribution，easy construction and being produced in factory to ensure its quality and reduce the construction cost and time．

Research conclusions: Through comparing the results of theoretical formulas and model analysis，the change tendencies of the thickness of corrugated steel webs ，wave height ，the obliquity of inclined plate，the width of straight section and the height of bean were obtained．

Research conclusions: There must be four basic conditions for occurrence of water － bursting． The rock plate is easy to become slack，resulting in water － bursting due to the change of the stress field of rock mass and the effect of water pressure in the tunnel． The principle of draining water to cut the water pressure，conducting the advanced support，and ponding muddy water along with draining clean water should be followed in karst tunnel construction．

Research conclusions: Combined with construction of Jinshazhou Tunnel of Wuhan － Guangzhou Passenger Dedicated Line，by analyzing every fact that influences the risk of water loss，the hierarchy structure model was developed with AHP analysis method to get every factor＇s relative weight． Based on the sort of compound weight，the risk factors having significant impact on the water loss risk of the earth surface were distinguished，and the weak points in all aspect were found out． So the effective measures should be worked out to control and reduces the risk and the impact of the tunnel on environment for ensuring safe construction of tunnel and achieving the effective control of the risk． Such theory，method and thoughts on control of the risk could be as the reference to the similar works．

Research conclusions: The " classification of geological complexity in tunnel construction " was researched and developed to realize the " geological prediction design for tunnel construction" and place it into the standard management range． This method could ensure the safe construction of tunnel and push forward the geological forecast work with obtaining good result．

Research conclusions: The research results show if the measuring point is embed after excavation of core soil，the losses settlement is large． The full － face curtain grouting can be used to reinforce the surrounding rock to achieve better control of the vault settlement of the tunnel． The removal of temporary support has small impact on the displacement of surrounding rock． Using the three bench method and center diagram method to construct the subaqueous tunnel ，the displacement of surrounding rock canbe controlled well．

Research conclusions: According to the characteristics of the economic development zone of west Taiwan Strait，the function orientation and development strategy objectives of the intercity rail transit of the city belt of the west TaiwanStrait are offered． According to the resource of the existed railway and railway under building in this area，the adaptation of the capacity is analyzed after implementation of the Long and medium － term Development of National Rail Network Planning，the plans on running intercity train on the intercity rail transit by using the railway surplus capacity are presented，and according to the characteristics of the city belt，the plan and construction plan of intercity rail transit as well as the plan of running the intercity train are put forward．

Research conclusions: When there are two fans with each power of 90kw and the total electric load more than 200 kW of the midway fan room and the distance of power supply is longer than 250 m，the high voltage power supply is always designed． Application of soft start mode to the high － power fan can cut the current of transformer＇s low voltage side，so the relative small capacity transformer is used with less investment． In case of the accident，the two fans can start at the same time with reliability．

Research conclusions: The freight traffic pattern of Dalian terminal is composed of five freight yards in order to coordinate with the urban overall planning，meet the urban freight traffic demand，achieve the concentrated and specialized management and enhance the efficiency of railway transport．