Research conclusions: (1)Based on the data of geophysical exploration，the anomaly of the lower resistivity can be sorted according to the anomaly shape and the value and the gradient of resistivity．(2)The V，IV andⅢanomaly gradations should correspond respectively with the V，IV and III surrounding rocks．On the other hand，the data of the tunnel excavation demonstrate that only with the data of the geophysical exploration it is difficult to distinguish V surrounding rock and IV surrounding rock．(3)Due to special engineering geological character of basalt，the comprehensive geological exploration，especially the geophysical exploration must be conducted in order to objectively evaluate the general engineering geological condition for the tunnel and rightly instruct tunnel construction．

Research conclusions: The integrated geophysical exploration technologies of taking high—precise gravity and magnetic measurement as the principal technology WaS used for the geological survey in iron meine goal in She County along the Handan—Changzhi Railway， obtaining a rather perfect result．Through the comparison and verification of the data got by means of high—precise gravity and magnetic measurement，seismic reflection，TEM sounding and tightly point spacing DC sounding metheds，the abnormal area and boundary of the 90af were mapped out，which could provide very useful geological basis for the goaf evaluation and railway alignment．The experience from this project has a great directive significance to the geological survey for railway in the similar situation．

Research conclusions: Several key issues of airborne LIDAR applied in railway survey are analyzed．Applications of airborne LIDAR in railway survey are conscientiously summed up，the parameters of airborne laser sensor in the condition of China's terrain condition are determined．And fully combined with specific projects，method and standard of point cloud classification for railway survey is mastered，accuracy authentication of airborne LIDAR result can be done through the authentication method of result precision of airborne LIDAR mentioned in the paper，observational result of airborne LIDAR based on UTM system through protection into engineering coordinate to get the geographical information system Can meet the requirement of railway survey and design before the project application．

Research conclusions: (1)The shield effect of hilgh velocity in the frozen crust of earth surface may be eliminated by installing wave—detector and the hiigh—frequency filter．(2)To avoid the shield effect of high resistance in the earth’s surface。the electrodes need to penetrate the frozen crust with direct current electric method．(3)CSAMT is a preferable method for geophysical exploration for long tunnel，but due to the complexity of the electron components and batteries of its transmitting system and receiving system，the cold—resistance capacity of CSAMT is inferior to MT．(4)The installation of MT is in a simple way that the electron and magnetic probe connect with host computer directly．In this way，the system interferer Can be reduced and probability of appearance of problem like complicated circuitry can be lowered．Simultaneity the cold—resistant capacity of MT is stronger，and MTU一5 A can explore objects with high accuracy if the interferer is small．

Research conclusions: In this paper, the introduction is given to the all-round reinforcement mechanism, design and calculation works of the compression dispersion -type anchor and the related matters for caution in the engineering application. Through the comparison and analysis of various anchor systems, the adapt ability of adopting the compression dispersion -type anchor to the Youxi Station was determined. The typical design calculation of the compression dispersion -type anchor was made according to the engineering geological conditions. The detailed discussion was made on the construction technology and the related matters for caution in the engineering application. The compression dispersion -type anchor presented in this paper can be as the reference to the design and construction of high cutting slopes for railway and highway in the mountain area with complicated geological conditions.

Research conclusions: From the comparison of the calculation results obtained with the traditional layed summation method，the secant modulus method and the angle of spread method for one actual construction project，it was found the results obtained with the secant modulus method Was close to the actual foundation settlement．This indicates that the secant modulus method iS accurate and available．

Research conclusions: It is feasible to reinforce the soft foundation of hish—speed railway with cement mortar pile because application of cement mortar pile can overcome the problem of the insufficient strength of the pile when using cement injection pile and plasma spray pile in cohesive soil with high plasticity index．However，the construction technology，reasonable water—cement ratio and gray—sand ratio，and the construction parameters of the cement mortar pile must be determined by test piling，so it is proposed to strengthen the on—site construction management when using cement mortar pile．In addition，the quality inspection of pile can be done by the core drilling along with load test．In order to ensure the effects of cement strength and reinforcement，it is not allowed the large—sized construction machinery to roll the upper embankment on cement mortar mixing pile within aging 0f 28 days．

Research conclusions: At first，the cooperative mechanism of pile—net structure subgrade was analyzed briefly．Then，taking the settlement of one subgrade section of Beijing—Shanghai Hish—speed Railway as the study object，the settlement in the reinforcement area was solved by using the composite modulus method and pile compression method， and the settlement of subjacent bed Was solved by using Boussinesq method and Japanese 1／3 method．The result of comparing it with the measured value showed that this method is reasonable and available for calculation of the settlement of pile—net structure subgrade．

Research conclusions: From the comparison and analysis of the previous upgrading schemes of some existing railway lines，such as reconstruction of single track，additional construction of the second line with partial upgrading of the existing line，construction of double track step by step and construction of double track by one time，it is concluded construction of double track by one time has features of saving construction cost，getting good economic benefits，high traffic quality，less interference to the other existing railway lines，and provding the wide space for further economic development and railway network construction．So the scheme of construction double track by one time should be adopted for upgrading of existing line．

Research conclusions: According to the principle of the square difference，the model for the divergence tolerance of elevation and altitude difference between adjoining points of hish—-speed railway with CP III Was derived．And with this model．the simulated calculation Was done for the analogue CPⅢvertical control network measured with German surveying method and China rectangle surveying method and its result Was consistent with the specification of divergence tolerance of elevation and altitude difference between adjoining points of hish—speed railway with CPIII stipulated in the current code for engineering survey of hish—speed railway．The research result provides theoretical basis for the specification of divergence tolerance of elevation and altitude difference between adjoining points of high—speed railway With CPⅢ

Research conclusions: Through doing the in—situ tests and making statistic analysis of the tested data for Yunmeng experimental section of the additional second track of Wuhan—Xiangfan Railway，the fitting curves of the ballast longitudinal and lateral resistance of the ballast bed for the III—type concrete sleeper were determined．Besides，the equivalent lateral resisitanee of ballast bed for the III—type concrete sleeper Was calculated．The results could be as the referances to design of the resistance of the jointless track．

Research conclusions: The angle deformation will appear when gauss projection is used in coordinate projection division of the different central meridians，which has a negative impact on the tack design of high—speed railway．Especially when the rectilineal side of high—speed milway is very long，this negative impact Call not be ignored．This impact on the track design of high—speed railway should be reduced by some ways，such as optimizing the position of the subdivision of projection of engineering independent coordinate and controlling the deformation sizes of the central meridian span and angle of adjacent gauss projection divisions．And also it is necessary to research the projection model and calculation method for the engineering survey to achieve the goal that only one projection division is used in a engineering project or fewer divisions are used in one engineering project

Research conclusions: Through the research on the structure type of turnout continious girder in the station throat zone ON ballastless and jointless track，the control sectors of choice of the bridge structure style in the turnout zone were summarized．In order to design the structure that can meet the strength and deformation requirements of the turnout on ballastless and welded turnout，the attention should be paid to the followings：(1)The demands of the ballasfless and welded turnout to the bridge deformation and girder gap position should be confirmed．(2)According to the demands of the ballasdess and welded turnout to the relative transverse displacement of rail at the position of girder gap，the reasonable transverse arrangement of girders should be confirmed．(3)Based on the confirmed bridge structure style，an integrated ballasdess and jointless turnout—bridge—pier mechanical model should be established to calculate the working conditions of the track. girder and substructure in turnout zone．(4)The analysis of entire or partial girder should be made．

Research conclusions: The bridge approach of Yinghe Bridge of Luohe—Fuyang Railway is a 32 m span girder．The main bridge bias crosses the Yinghe River that is a IV class navigable fiver and it requires the bi-·direction navigation under one span．After verification of navigation and comparisons of the construction schemes，it wag decided to use 128 m simply—support steel truss girder due to the limitations of the clear height and clear width．As the construction condition was poor and the navigation could not be affected during the construction period．it needed to install the scaffold on the river bank and temporary buttress in the fiver．The girder assembly Wag conducted on the scaffold and the guide steel truss girder Was installed on the front end of the steel truss girder．The steel truss girder Wag erected with semi—cantilever dragging method，In this way，not only Was the navigation requirement met during the construction period，but also Was the construction time saved．

Research conclusions: From the experimental research it is concluded to properly increase the concrete aging at stretching prestress and the secondary permanent load time can decrease the later shrinkage deformation of the structure．When the temperature is fixed and humidity increases，the displacement of the upper arch in the middle of the span decreases，and when the humidity is fixed and temperation increases，the displacement of the upper arch in the middle of the span increases．

Research conclusions: The design of the anchor—-box test model for the Huangpu Pearl River Bridge is reasonable and the model can reflect the actual mechanical behavior of the bridge．The anchor—box type cable—girder anchor structure can transfer the stress smoothly and safely and it meets the functional requirement of the long span steel cable. Stayed bridge。

Research conclusions: To the steel—truss girder cable—stayed bridge，firstly，the length of the upper chord should be set as variables and the multiple constraint equations should be established to the influence vectors of the the length change of the upper chord on segment camber or other restriction conditions．Then，the solution circumscription should be given and the most closed ones should be solved to get the pre—camber that is the most closed to the theoretic results of the multiple constraint equations．Finally，the theoretic solutions should be rounded，merged and adjusted to obtain the rather ideal pre—camber．

Research conclusions: ：(1)Under the condition of trains meeting at one time，the subsidence of any parts of supporting structure is less than 2 mm and both the maximan tensile and compressive stress are less than the design values．The displacement and deformation of supporting struture can satisfy the design requirement．(2)Under the effect of long—term load of train，the accumulated deformation of typical cross—section of the foundation base is less than 20 mm，which meets the related requirements and has not devastative effects Oil the long—term service of the track．

Research conclusions: This paper describes a design of the section post in tunnel and the key points of selecting the equipments．In this design，the main wiring is simplified to save the field and the equipments are of dispersed layout for easy transportation and replacement．This paper also puts forward the key and difficult points for design of section post in tunnel according to the environmental speciality of the section post in the tunnel，researches the earthing of the section post，and introduces the principle of disaster prevention to make the section post in tunnel normal operation and provide the reference to the similar design．

Research conclusions: According to the calculation principles, for the track where only the single -unit EMU composed of 8 coaches runs, it is suggested that the minimum distance between signal and electric phase splitting should be not less than 217. 5meters. For the track where the twin -unit EMU composed of 16 coaches runs with speed of 200 km /h, the minimum distance between signal and electric phase splitting should be not less than 431. 05 meters, and when the distance is notup to 431. 05 meters, the average start gradient should be no more than 15. 5‰.

Research conclusions: The research shows that the symmetrical three—way turnout is available for urban rail transit with rational design parameters and reliable structural strength．The symmetrical three—way turnout is not only safe and reliable．but also can effectively shorten the excavation length of the subway station访tIl stabling siding and is helpful for saving construction investment，debasing project risks and reducing the construction difficulty．So the symmetrical three—way turnout Can be applied widely in urban rail transit．

Research conclusions: According to the successful experience of applications of BIM in building and highway constructions，it is believed application of BIM in railway design has great significance to improvement of the design productivity，decrease of reworking design and misunderstanding the design ideas in construction，and even improvement of the integral level of railway construction．It is proposed application of BIM in railway design can be realized phase by phase and step by step to provide the initiatory basis for developing multi—specialized compositive BIM 3 D visualized design software platform．

Research conclusions: Control and management of construction project cost is a process management from the investment decision—making to the final settlement of account for final completion of construction project and is also a systematic project with no dispensable part．Only all costs of the whole construction works ale controlled Call the goals Can be achieved．A systematic and integrated method should be used for controlling the whole construction process to eliminate the”Three Excesses”phenomenon，control the construction project cost reasonablly and effectively and save the construction cost to gain the maximum economic and social benefits．