Research conclusions: Aiming at the development trend of the latest earth observation technology development，on one hand ，the applied potential of the existing earth observation technology and data should be unearthed，and on the other hand，the research and application should be strengthened for the latest earth observation technology and its achievements，such as the digital aerial photography，the airborne laser radar and the high resolution satellite image data． Not only can the earth observation technology be applied in the national basis mapping，but also can be applied in the railway topographic mapping，railway track alignment，railway engineering geologic survey and railway environment evaluation．

Research conclusions: For solving the problems mentioned above，a method is offered for integration and sharing of the metadat － based mapping data，the standard is worked out for the railway mapping metadata and the connection chart －based three － dimensional visualization inquiry technology is developed for providing the powerful means for the management and application of the railway mapping data． The research result shows this method can meet the demands of the normal management and high － efficient application of the railway mapping data．

Research conclusions: The vibration of the construction machines was the main reasons for the karst ground collapse．After completion of the construction，the karst ground collapse did not have serious impact on the groundwaterenvironment and ground stability． In construction of high － speed railway，the influence of karst ground collapse on thesurrounding environment should be adequately considered．

Research conclusions: The load bearing and deformation laws of the embankment U － shaped structure are analyzed to obtain the change law of the stress － strain of the bottom plate and side － wall corresponding to the structure height and thickness． The moments of X axial direction of the bottom plate and side － wall are the control moments． The max moment of bottom plate is on the side － wall，and the max moment of side － wall is on bottom． The embankment U － shaped structure has features of higher whole stability and less deformation and it can control the subgrade deformation effectively．

Research conclusions: No matter entering the chamber under the working pressure or under the normal pressure，it was necessary to take the corresponding ground reinforcement measures to improve the stability and compactness of the stratum around the shield machine for guaranteeing the safety of construction． When entering chamber under working pressure for replacing the cutters，the back grouting could be used step by step for reinforcing the ground surface． When entering chamber with normal pressure for replacing cutters，the drilled pile could be used along with grouting between piles for reinforcing the ground surface．

Research conclusions: The train load on the the subgrade top was down transmitted almost along the 45°direction． The load was overlapped in the bedding bottom under the effect of the train loads on the multiple tracks． The vertical stress in the foundation base caused by the train load was distributed unevenly and it was distributed with a curve that the stress in the middle region was bigger than that in the periphery． The maximum vertical stress appeared in the middle of the subgrade bed under the effect of the symmetrical train load．

Research conclusions: In the design of a high standard railway cut slope，not only must the cut slope stability be considered，but also must the durability and beauty be considered． Only both of them are achieved，the perfect effect can be obtained． According to the geological characteristics of the slope，the slope stability should be analyzed，the rational reinforcement measures should be taken and the drain system should be improved． In this way，the long － term durability can be obtained and the perfect environmental beauty effect can be achieved．

Research conclusions: Under the condition that the coordinates discrepancy of CPⅢ points in adjacent two overlapping sections are lower than 3 mm after independent adjustment，the overlapping smooth results obtained with these two methods can meet the demand of checking the long and short waves of the track． From the angles of the survey theory，practice and application，the rigorous adjustment overlapping method is more reliable，its maneuverability of the overlapping data processing is better，and it is more available for the engineering survey．

Research conclusions: The heavy haul railway is a system engineering，so in the research the following principles should be followed: the equal stress should be laid on the track subsystem and other subsystem，on the theoretical research and experiment research，and on the new track component research and new maintenance equipment research． Especially， the structure theoretical research must be stressed，the new track structure research and new track components research should be promoted，the detection and maintenance technologies of the track of heavy － haul railway should be strengthened，and the development of professional large － sized permanent way maintenance machine should be speeded up．

Research conclusions: In the durability design of the segment joint，it is important to set up the reasonable number and positions of segment joints and well make the structure design of the shear connector，and at the same time，the attention should be paid to the index requirement of the epoxy adhesive． If the bridge is of the prestressed structure，the full prestressing system should be adopted． The structure calculation and prestressing tendon adjustments should tally with the technical features of precast gegment assembling bridge． The grouting quality of pretressed pipe should be strictly controlled，and the attention should be paid to the shock absorption and anticorrosion of externally．

Research conclusions: The squeezing deformation of surrounding rock can be predicted by strength stress ratio value F， and it is proposed to use the Hock － Brown strength criterion and GSI method to estimate the rock mass strength and use the maximum crustal stress trending to the tunnel as the crustal stress in the strength stress ratio value F． Usually，the destroy of the squeezing deformation happens when the F is less than or equal to 1 and the severe squeezing deformation happens when the F is less than or equal to 0． 5． Therefore，the 0． 5 and 1 can be separately used as the critical values for the squeezing deformation with different degrees． The practice shows the value F method is reliable for prediction of the squeezing deformation of the surrounding rock．

Research conclusions: As the included angle between the maximum horizontal principal stress direction and tunnel axis direction of the Cuihuashan Super Long Tunnel is over large，the rock outburst is inevitable． The conclusion that there is possible to happen thge rock outburst obtained by calculating stress parameters and rock parameters has a certain one － sidedness． The construction practice of the Cuihuashan Tunnel proves that the rock outburest should be assessed by using various criterions to make the prediction closer to the actual situation．

Research conclusions: The comparison is made between the whole load bearing situations of the grid structure of the west and east sub － station building when using a bidirectional spring support and a fixed hinge support． The calculation and analysis show using a bidirectional spring support can much cut the horizontal thrust of the roof grid structure on the column of the bearing frame and the temperature stress． In this paper，the time － history analysis is also made under condition of the seldom earthquake to know the maximum deformation volume of the grid structure support under the effect of the seldom earthquake． The allowable deformation volume of the bidirectional spring support should meet its maximum deformation volume caused by the effect of the seldom earthquake．

Research conclusions: The infrastructure maintenance base of passenger dedicated line should be designed on consideration of the whole railway network in China． The distribution and functional orientation of the base should be chosen reasonably． The base site should be selected on the premise of meeting the requirements of the railway plan． The comprehensive decision should be made on consideration of the various factors to reduce the impact on the environment． When making the general layout design of the base，the layout should be reasonably compact without disturbances of various production and maintenance processes each other and the design of various pipelines should be improved with the reserved condition for future．

Research conclusions: Whether the track alignment is reasonable or not directly impacts the efficiency of the whole urban transportation system because the valley city is limited by its topographic condition and the road resource is in short supply． The track alignment of the rail transit in the valley patten city should consider the influence factors，such as the subjective and objective stream corridor，avoiding the passenger flow in one direction，the demand of the passenger crossing the river and natural gulley．

Research conclusions: ( 1 ) When the train passes through the single junction track with small track spacing，the otation angle of the bogie on worst position was in the allowable range of the bogie structure property． The rotation angle and stroke of the train couple on the worst position were in the allowable range of the train couple structure property． ( 2) The train speed did not exceed the 20 km/h when the train run on the single junction track with 3． 4 m track spacing in side direction without passenger． The train speed did not exceed the 15 km / h when the train run on the single junction track with 3． 4 m track spacing in side direction with passenger．

Research conclusions: The vehicle base of urban rail transit should be designed according to the research objectives in various design stages and the goals that should be achieved in the corresponding stages． Putting the interface in order should be strengthened，the interface relation should be straightened out，the interface standard should be clear and definite，the key points of the interface should be grasped and the measures for prevention of the interface risk should be mastered．

Research conclusions: ( 1) Besides satisifing the interchange needs of tranportaion，the metro transfer stations should be designed with the design and construction of the relevent municipal projects at the same time，and coordinated with urban development． ( 2) The under － construction urban areas can make use of the opportunity of metro constructionto to improve the urban underground space construction to make the regional transportation organization better．

Research conclusions: Taking the design of the Taiyuan Metro South Station as an example，this paper describes the traffic streamlines used for the passenger transfer in the underground central transfer hall between the metro station and high － speed station to make all streamlines unobstructed among the high － speed railway，metro，parking area， commercial area and square，analyzes the special treatment method for the underground engineering approach of the metro across the Taiyuan South Railway Station，suggests to us shield construction for this area，and looks forward to the regional transport hub that will promote the development of downtown business district and become the typical leading model of three － dimensional development of the regional transport hub．

Research conclusions: Staring with the system theory，the decision － making evaluation index system is established for the bidding scheme for the BOT project of passenger dedicated line and the evaluation is made with grey situation decision － making model． In the railway BOT project，there are lots of factors to influence the project risks and it is difficult to determine the relations among the influence factors． Now the commonly － used evaluation methods include thecomprehensive fuzzy evaluation model，ANN model and so on． These methods have their own advantages，but also they have disadvantages． With these methods，the differences of the comprehensive optimization index values are not obvious of various schemes and the model results are affected by the objective factors． Especially，with these methods，the high risks of railway BOT project can not be considered． The result of the model presented in this paper can not be affected by the objective factors，so this model is more accurate and effective in revealing the differences of the comprehensive optimization index values of various bidding schemes． This model has universal property，so it can be available for BOT projects of the highway and power supply．

Research conclusions: This paper deeply analyzed the development characteristic of the survey ＆ design enterprises from the enterprise scale，development mode and profit mode． Through the research，we thought the international trait and the function of lump － sum contracting have become the keys for the transformation to international engineering companies． Domestic survey and design enterprises should be the pioneer of going out，execute the strategy of international operation，and build the international trait． At the same time，we must promote business model change from the ability oriented to demand oriented，optimize the product structure，and cultivate the function of lump － sum contracting．

Research conclusions: ( 1) As the downtown population and traffic pressure increases，the urban layout extends to the outside areas，suburbs and satellite towns of the city． The appearance of large － capacity urban rail transit can save the usage of the economical land and ease the urban traffic pressure． ( 2) The development of suburban railway and inner － city railway can ease the suburban and inner － city traffic pressures to undertake the transportation task that the highway transportation can not do，and it also can open new areas for railway transportation．