Research conclusions: The strong wind in the strong wind area along Lanzhou—Xinjiang Railway mainly belongs to inland cold wind with the characteristics of high wind speed，long wind season，stable wind direction and quick winding due to the narrow tube effect，downhill wind and large convection current of atmosphere caused by the topography．The field measurement shows that the effect of windbreak is significant，namely the speed of the wind behind the 3 m hish windbreak iS much lower than that outside the windbreak and the shielding scope of windbreak exceeds 38m when wind speed is 20m／s，which effectively weakens the train overturning moment．However，it is necessary to do the further research on the effect of windbreak on reducing the wind disaster under different conditions and the conclusions offered in this paper can provide references to control sandstorm Mong railway in the future．

Research conclusions: The following conclusions can be obtained from the study on subgrade subsidence deformation and the prediction of the subgrade subsidence of Wuhan—Guangzhou Passenger Dedicated Line with the curve fitting method：The total subsidence in the subgrade center is bigger than that in the right and left subgrade shoulders and the total subsidence curve in the subgrade center is basically consistent with the grade rate of curve of right and left subgrade shoulders．The biggest subsidence is not in the subgrade center，but in the place 1—2 m away from the subgrade center．The predicted results with double curve fitting method and exponential curve fitting method are over big and the predicted result with three—point method iS over small．However．the predicted result with Asaoka method is mediated with no especial requirement of prediction time and hiigh accuracy．The subsidence can be controlled well by adopting CFG pile composite foundation．

Research conclusions: Through the analyses the deformation of strip exterior—protected construction for foundation pit，optimum of measurement spots and analyses of the measured data，the followings are concluded：(1)The horizontal displacement of the exterior—protected construction depends on the excavation depth，width of foundation pit，soil nature，wall rigidity and embedded depth．(2)The measurement spots for the displacement of the wall top should be installed from the span center to both sides evenly，and the measurement spots for the wall should be installed at the supporting place of slightly higher than the deep excavation place with the beginning from the center and from top to bottom．(3)The real—time monitoring should be done in the course of the excavation for predicting the deformation regulation，taking preventive measures in time，lowering the deformation speed and guaranteeing the optimum of measurement spots and the construction safety．

Research conclusions: The researches and applications show the”Floating Method”and”Rolling Pad Method”can effectively solve the problem of the displacement of reinforcing cage with the characteristics of fast and easy operation and no adding investment．The”Duct Fetching Grout Method”can be used for the pile breaking in the cause of grouting， but it is necessary to fabricate the grout collector before the pile foundation construction．The twice as much can be accomplished with half the effect if the condition is possible．In this way，the accident possibility can be reduced much．

Research conclusions: The parent metals of U77 MnCr rail is suitable for being used in the straight section of heavy—haul railway because of its high purity and good strength—toughness，has a perfect cost performance because it only contains the cheap chrome alloy of 0．25％一0．40％with good elasticity and does not contain the treasure vanadium alloy，has a good welding performance with self—harden ability of welding joints，SO it does not need air cooling after normalizing and the toughness of the rail top surface matches the toughness of the parent mental，and has a good fatigue resistance that can prolong the service life of the rail on heavy—haul railway．

Research conclusions: This paper mainly studies the intermediate angle consummation method and the program compensation method for track measurement with electric total station．The study and practice show these two methods are helpful for improving the accuracy of positioning electric total station．The intermediate angle consummation method is recommended when the environment is good and the program compensation method is recommended when the environment is bad．However，these two methods can be used together，which can further improve the the accuracy of free—positioning electric total station．

Research conclusions: It is concluded from the research the key points of quality control for double—slab ballstless track can be seized through choice of the construction programs，and the construction procedure and technique can be improved by analyses of the data of the technique tests and the other tests done before the construction．Upon it the engineers can fully master the quality control technology and measure for double—slab ballastless track for improving the construction quality and track accuracy．

Research conclusions: The EMU test with the speed of 35 1 km／h on the experimental line shows the all properties of the slab track satisfy the design requirements and the key technologies for laying the CRTS I Slab Track is successful．The triangular compass and portal frame are used for fine adjusting the slab with fast speed and high accuracy．After adjustment，the elevation error of the top surface of the slab is less than 1 mm，the error between the central line of the slab and the central line of convex retailing stand is less than 1 mm，the gap error between the slab and retailing stand is less than 5 mm. and the high—low regularity and directional regularity between the slabs are less than 2 mm，so the technology can be widely used for laying the slab track．

Research conclusions: ：(1)The elastic support of the diaphragm affects the whole load—bearing capacity of the section of box beam to some extent and the transverse beam can easily and directly improve the load——bearing capacity of the roof，SO with consideration of the advantages of each design program，an integrated program should be made to improve the load—bearing capacity of box beam．(2)It can be seen from the change law of axial force of boom that the axial force of the boom in all calculation programs has no change basically．It shows the diaphragm or transverse beam installation only changes the transverse rigidity of box beam and has a little influence on the vertical rigidity of box beam， and it also verifies again the elastic support effect of the diaphragm only changes the force transfer way in the box beam and has no obvious innuence on the rigid ratio of the beam and arch．

Research conclusions: The checking calculation methods for the strength and stability of the continuous girder bridge under frequent earthquakes and the ductility of the continuous girder bridge severe earthquakes are proposed，which cover the shortage of the Code and provide the theoretical basis for the seismic design and evaluation of the seismic property of the continuous girder bridge．

Research conclusions: Through the static and dynamic 10ad tests，the parameters about stress，deformation and frequency of the bridge are obtained．The tests results show the theoretical analysis and calculation method uses for the bridge are feasible，and with which the construction quality can be guaranteed and the rigidity and load bearing capacity of the bridge can meet the requirements of the design and relative standards．

Research conclusions: As sectional design is conducted by means of the direct estimation formula regarding the girder height estimation based on beating capacity of normal section，it not only Call，when meeting the requirements for beating capacity of normal section of girder and economical reinforcement，conduct sectional design by using the limit value of span—height ratio which meets the requirement of deflection control，but also can conduct optimum design of some bending members with large sectional dimension with consideration of control of bearing capacity of normal section and deflection．With the common—used reinforcement ratio scope of q [0．6％，1．5％]，the reinforcement ratio based on the ultimate bearing capacity increases with the increase of the load under the condition that girder sectional dimension and material strength remain unchanged．Meanwhile，the mid—span deflection value increases in spite the girder rigidity is improved to some sense．Therefore，upon calculation of maximum crack width，although the increase of load will lead the change of relevant parameters，but the increase of reinforcement ratio can better control the crack width．

Research conclusions: Based on the analyses and calculation of the climbing capacity，hauling capacity，braking capacity and remaining the level of machine aiTas of JQI60 bridge girder erecting machine，the plan for upgrading JQ 160 bridge girder erecting machine Was put forward and applied in Bidding WI of Yichang—Wanzhou Railway．This upgrading plan Can expand the applicable scope of JQI60 bridge girder erecting machine can be expanded to 18‰long gradient with meeting the technical and safety requirements of girder erection at 1 8‰ long gradient．

Research conclusions: The section design of railway tunnel for heavy haul traffic based on the Taihangshan mountain tunnel for mixed passenger and freight traffic is basically feasible．The simple grate layer should be canceled to the railway tunnel for heavy haul traffic．The invea should be installed when the surrounding rock grade is m or above．The ratio of rise to span and the depth of the invert should not be lower than the standard for passenger dedicated line tunnel．Lots of tests on site and measurements must be done before working out the tunnel technical standard under 30t axis load because of the complexity of train load and variance of the surrounding rock．

Research conclusions: With establishing the functions for the bearing capacities of the head—on Cross—section and oblique section of the shield tunnel lining，the analytic formulas for the bearing capacity of head—on Cross—section with big and small eccentric center and shearing resistance of oblique section are offered．The sensitive analyses of the random variations of the functions for bearing capacity are made with an example．It is concluded for the bearing capacity of the head—on cross—section，the sensitivity of random variations is different when using the functions with different expressions，the Pv has the biggest influences on the functions for the bearing capacity of head—on Cross—section oil the arch top，and the f,has the biggest influence on the functions for bearing capacity of the oblique section on the arch web．

Research conclusions: The fracture of monolithic concrete bed in tunnel has t}le characteristics of concealment．Sudden occurrence and continuity．The causes for the fracture are the dissolution and corruption of underground water，defaults of construction and maintenance and shoItage of maintenance．The measures of dredging underground water，adjusting the track gradient partly and mud jacking can be taken for the fracture．The practices show the perfect result has been got by taking these measures．

Research conclusions: The functions and efficiency of the selected equipments have been verified through the application of the selected equipments in curtain grouting for construction of one single line tunnel．The result shows the grouting requirements Can be well met by adopting the imported muhiple—function drilling machine along with China— Made grouting machines．

Research conclusions: Compared with the absolute measured deformation，all calculated deformations were in the controlled ranges stipulated in the codes and standards based on the pre—measured and simulated results．Therefore，for construction of ultra—high sectional and ultra—shallow—buried tunnel under the condition of weak—water rock．the establishment of ANSYS simulation model with 100 percent of the stress release by the plane strain mode could meet the demands of the process control and optimization．For construction of the tunnel with CRD method，the simulation results showed that settlement of 2，4，5 and 7 subsections accounted for 85～90 percent of total settlement under the complex conditions．Based on this，the space—time sequence of excavation was optimized in the ways that the excavation method of the reserved cole soil was used along with the stepped CRD method．The sequence was firstly to cut through the upper step is and then to cut through the lower step．The practice has proved that this optimized method is safe and reliable．

Research conclusions: The improved and innovative construction method for secondary lining of railway tunnel simplifies the construction procedure．The problems of bad outlook of secondary lining and water penetrating and leaking in the joint of low wall with side wall can be overcome and the tunnel construction cost call be reduced by adopting these construction technologies．These technologies also can be used in construction of highway tunnel．However．as the new technologies，these technologies need to be verified and improved in more construction practiced．

Research conclusions: The studies show the train speed has a significant impact on track structure vibrations．The sleeper vibration speed and the peak value of the reaction of monolithic track bed increase with the increase of the train speed．The track irregularity also has significant impacts on track vibrations．So the routine maintenances of rail wheels tread and rail surface are very important to reduce the track structure vibrations．In addition，the rigidity of rubber pad between sleeper and monolithic track bed has significant impact on track vibrations．The sleeper vibration speed decrease and the reaction of monolithic track bed increase with the increase of the rigidity of rubber pad，but the corresponding spectrum does not change．For the tunnel structure security，the rigidity of rubber pad should be decreased．

Research conclusions: Combining with the characteristics of service functions and structural style of the Futian Underground Railway Station，the fire resource of the station is identified，and the fire load and scale are analyzed，that is to take 2MW as the scale of luggage firing and manual setting fire，10MW as the scale of shopping fire and 16MW as the scale of train fire．According to the characteristics of underground space structure，the fire dangers in the different areas and the difficulty of evacuating persons，the method for 3 hierarchical management of fire resource is offered on the base of the different fire dangers and adopting the different fire monitoring modes and different management methods for the he different areas．

Research conclusions: The study shows (1)Africa has extensive highway project contracting market．(2)Most of the African highway projects adopt”Design—Build”management system．(3)African highway design mode is more closely combined with the construction site conditions．and the content of design is more complicated and detailed(4)For African highway project，the contractor faces the various risks，SO the Chinese enterprises should fully investigate the situation，and adopt useful measures to reduce the risk to the minimum．

Research conclusions: Based on the consideration of the constraints and uncertainties of resources to the construction projects，the new method is offered for making construction project schedule with critical chain method，namely using improved genetic algorithm to identify critical chain，determine the optimal start time of each activity under a desirable schedule and present the algorithm for determining the sizes of the project buffer area and feeding buffer area．The feasible and stable project schedule can be made with this method．because this method integrates the advantages of critical chain method and focuses on the whole project．This method is especially suitable for making the project schedule under the constraints and uncertainty of resources and Call be as an effective tool for making the project schedule．