Research conclusions: Connecting with the main restraining factors to route location of hiish—speed railway，the route location principle concepts including geological location，priority site selection to major project，environment protection，planning，resource and Cross—section route location have been put forward in this paper，which emphasizes focusing on the major and free the minor while determining the alignment of railway，making a difference between key route and nonessential route，allocating the resources rationally to avoid waste．In route alternative，investment should be strictly controlled but not the sole factor taken into account．None but the route scheme with proper investment and optimization of social comprehensive benefit shall be optimal scheme．

Research conclusions: The curve radius at both sides of the station of passenger dedicated line should be chosen with consideration of the terrain conditions and calculated on the base of the minimum train speed．If the terrain conditions permit．the 1 1 000—12 000 m curve radius and the max．transition curve stipulated in the code should be adopted．For considering the further speed—raise in future，it is advised the transition curve length should extend 30 m，when adopting 1 1 000～12 000 m curve radius．

Research conclusions: Through analyzing the construction standards and technical measures for various infrastructures and auxiliary projects，to further raise the railway speed is feasible．By adjusting partial ballast thickness，improving the grades of ballast and reinforcing the subgrade，the goal of running 250 km／h train can be achieved．On the whole， transportation organization and various engineering technology can adapt to the requirement of running 300 km／h train in future，but transportation pattern and signaling system should be further studied and perfected．

Research conclusions: Compared with the railway with max．gradient of 6‰，the investment in the railway with max． gradient of 4‰will be increased by 400 million RMB，accounting for 2．5％of the total investment．However，the traction weight of he railway with 4‰ gradient will be up to 7，250 t，80 it is suggested to adopt 4％t gradient for meeting the requirements of heavy—haul transportation，large vehicle in the future and being uniform with neighboring main line of the railway network in the criteria．As there is little subgrade filling materials in plain terrain．it is suggested to use the impmved soil grade A to the surface layer of subgrade and the improved soil grade C to the bottom of the subgrade with rolling compaction to lower the cost and enhance the implementation．

Research conclusions: The abnormity of pipelines is obtained from the common offset profile by making simulation for the detection of underground pipelines．The result shows that using FDTD to simulate the mechanism of GPR is feasible． The actual positions of the underground pipelines ale known by using migration imaging．The result shows that migration imaging could make the object back to the original position and obtain underground actual image with high transverse resolution．

Research conclusions: With the precisely determined geoid model，the GPS control network spot is fitted in height and the internal and external accuracies of the precisely determined geoid model are checked and analyzed．The result shows the accuracy of the precisely determined geoid model is better than±3．5 cm．the normal height with centimeter—level accuracy can be got and this really achieves the three—dimensional positioning function of GPS technology in the geometry and physical senses．Compared with the traditional standards of leveling measurement，by using the precisely determined geoid，there is no error accumulation，the labor intensity can be much reduced and the working efficiency Call be improved．Under conditions that the traffic is inconvenient and topographical condition is complicated，the calculation accuracy of the normal height Can reach at centimeter level by using the high—resolution geoid model，which is a big leap in railway level surveying．

Research conclusions: The correlation degree of the soil mound pile is decided by making gray correlation analysis． With the aid of the linear—weighted method，the gray model is integrated with BP neural network to optimize the noisy—reduction for sole model．By adopting parallel gray neural network，the effective static load test data of sole pile in the area of the similar soil layer are predicted，and the errors are compared．The results indicate that overall factors could be considered in this approach，and the decisions of missing data remedy in the test，fitting of known settlement，prediction of future settlement and reference value of foundation pile settlement have practical values in correlation region．

Research conclusions: (1)The displacement in top of the front pile in portal double—row pile is obviously small than that of single—row pile and double—row pile without coupling beam，when the distance between two rows is big．(2)The max．moment and shearing force in the front pile are close to the back pile and the absolute value of positive moment and shearing force are close to the negative moment and shearing force．The coupling beam has an obvious effect on coordinating the moment and shearing force between the front pile and the back pile．(3)The parametem choice of the karst soil is an important influence factor on design of friction pile．(4)Portal double—row pile has lateral rigidity to effectively restrain the lateral deformation of exterior—protected construction．(5)To the side slope of expansive soil，the excavation and support should be conducted in time during engineering to reduce the disturbance of the water content and soil body by the engineering．(6)The numeral calculation should be adopted along with the experience for ensuring the stability of side slope．.

Research conclusions: It is proved that the border conditions，such as buoyant force of underground water，leakage，soil pressure have a great influence on the design and construction of the underground engineering in the area of complicated engineering geological and hydrological conditions，80 all the influence factors should be taken into account in the design to ensure the safety of construction and operation in future．It is feasible，reasonable and safe to adopt dock structure for underpass of highway under complicated engineering geological and hydrological conditions．

Research conclusions: (1)The stability of dyke in declining gully is influenced by the lowering base gradient，the cohesion of base contact surface and friction coefficient．(2)It is inappropriate to build a dyke on the ground directly when ditch gradient is more than 5％，and the dyke base should be made flat if possible．(3)It is appropriate to regard the cohesion of base contact surface as zero because the base contact surface is immersed in water for long term to drop the cohesive performance．

Research conclusions: (1)The main default of the karst subgrade of Luoyang—Zhanjiang Railway is the subgrade settlement．The penetration corruption caused by the fluctuation of underground water，vacuum absorptive corruption and pumping underground water by human being are the reasons for the settlement．(2)The treatment principles of karst subgrade are as follows：To the embankment，grouting will be conducted，to the road cutting，the principle of combining prospecting with grouting will be followed and the verification will be made by prospecting and boring，to the deep buried carst cave，the grouting will be conducted after flyash and mortar fillings，to the open or shaUow buried karst cave，the refilling will be conducted after excavation or the concrete cover plate will be added．(3)In the prospecting and grouting process，it is necessary to pay attention to the changes of grouting pressure and environment and control of grouting quality for getting perfect grouting result and good stability of the karst subgrade．

Research conclusions: The construction scheme of the foundation pit for integrated transport hub should be determined in accordance with the overall thoughts．The construction scheme and the relative parameters should be chosen with numerical simulation and calculations．As there is no criterion for determining the parameters for the exterior—protected construction for the multi—step foundation pit，80 the parameters for the exterior—protected for such foundation pit should be determined in accordance with the ratio of unloaded width(B)and foundation pit depth(H)，the construction method and dewatering condition．For arranging the large—space bracing system and determining its parameters，the concept and principle of equivalent stiffness and even stiffness should be followed and the influence factom of the change of environment temperature，heave and settlement of the bracing column and construction loads should be considered．

Research conclusions: For the section with the special technical requirements and control sector，the plane design standard for the railway line should be decided in accordance with the operation situation of construction project and researched result of V—S curve．For the sectional track，the plane design standard should be reasonably selected after analyzing the relation of the speed difference between the cross—line train and hish—speed train and deciding the reasonable comfortable level of train and relative super—elevation of track in accordance with the operation situation of construction project and researched result of V—S curve．For the tracks on both ends of station，the plane design standard should be selected after analyzing the relation of the distance between the curve and the center of the station and the relation of the speed difference between the entering and departing trains and high—speed train，and deciding the comfortable level of train and the super—elevation．

Research conclusions: The experimental study results show that the glass foam revetment is better than the sward revetment in insulated during the experimental period, which can reduce the seasonable thaw

Research conclusions: The results of comparison and verification of considerable calculation cases show that AFPA is feasible and reliable in computing reinforcements for random reinforced concrete section and in computing the stress redistribution for random concrete section；and the computation by means of AFPA show the diaphragm set in the middle of bi—directional stressed hollow section has a little effect on controlling sectional rebar stress and crack width.

Research conclusions: The monorail adopted in the Phase I of Jiaoxin Line of Chongqing light rail was the first time for China to use it．The structure of the used T—shaped pier Was reasonable，which adapted to the characteristics of monorail pressure．The selected loading met the requirements of the various construction conditions and service condition for monorail．The precise design of the parameters for bearing pad—stone not only met the construction requirement，but also broke through the Japanese monorail construction mode that the pier Was constructed first and the beam is constructed late．

Research conclusions: In the calculation of expansion force，the same calculation method as that for simply—supported beam or continuous beam Can be adopted for the of expansion displacement of basket handle arch bridge．The max．Flexural displacement caused by train load is less than the expansion displacement caused by temperature change，and the rail flexural force is less than the rail expansion force．So in general，the flexural force does not control rail calculation，but it may control the design calculation of piers．

Research conclusions: There are the big differences in the culvert design，layout of bridge deck，calculation of train braking force and traction force，braking force on pier of continuous beam bridge，distribution of braking force，limited value of deformation of creep on beam，calculation method of pile foundation and principles of reinforcement of pile cap between China Railway and German Railway．Through communication and discussion，the reasons for the differences are known and the reasonable opinions of German experts are listened to，which can provide the reference to improving the construction quality of bridge and culvert in China．

Research conclusions: (1)In the settlement computation of bridge pile foundation in collapsible loess zone，the influence of negative friction resistance should be considered．(2)In design，it is reasonable that the total settlement of not more than the specified value is adopted for controlling the settlement of bridge pile foundation．(3)For the bridges in collapsible loess zone along the railway from Sanmenxia to Linbao，adopting the modified code of railway bridge to compute the total settlement of pile foundation can control the design．(4)The modulus of compressibility of soil beneath the pile bottom is the main influence factor on settlement computation，so it must be preciously measured during prospecting．

Research conclusions: As the materials for cable structure have good performances，the cable structure is widely used in bridge．For ensuring the service safety of the bridge for long term，the antiseptic measures should be taken to the cable structure．At present，the basic antiseptic measures for cable structure materials are mostly galvanizing by hot—dipping and epoxy spray coating．

Research conclusions: (1)The main innuence factor for the tunnel scheme is the Heilongtan karst runoff which drains as spring groups to Heilongtan at the foot of Xiangshan Mountain，north of the ancient city Lijiang．The spring water is mainly supplemented by atmosphere precipitation in about 121 km2 kant depression zone，including Jiuzihai，Lariguang and Hongshuitang areas．This karst run off zone is a relatively independent vein runoff with a small hydraulic gradient and low flowing velocity．(2)The principle of route selection for the tunnel：Based on the researches on the harm of karst water to the tunnel and the influence of the tunnel excavation on the kant water system，the tunnel route should keep away from water concentrating area like large—scale corrosion basin or depression etc．and upriver karst runoff zone close to the reehar舀ng area．The route in front of the tunnel line should be heightened，SO that the tunnel can pass safely through the kant safe area close to the drainage area．

Research conclusions: Improvement of emergency systems is the base of urgent repair work．The scientific thoughts 0n urgent repair work is the core for guiding the urgent repair work．Rapid action and flexible working style are the principle of the urgent repair work．The perfect survey and design works for the traffic facilities in mountain area are the premises Of preventing and reducing disasters and are also the basis for studying the program of changing route．

Research conclusions: The maximum traction 10ad of section post arises under the conditions that the fleet trains run in the heavy—duty direction and no train runs in the light—duty direction．Both the maximum 10ad current and the maximum equivalent current in the section post increase linearly with the increase of train quantity．The max．Equivalent current of the section post can be taken approximately by 30％of the total current separately feeding to the up and down tracks at the first end in the heavy—duty direction when there is less fleet train and call be taken by quarter when there is much fleet train．

Research conclusions: The adaptive genetic algorithms decides the cross location，cross rate and variance rate of chromosome based on the individual adaptive value in calculation process to make the cross moving to the algorithms convergence direction，which ensures the filial generation is better than father generation，make the start phase variable obviously and later phase stable slowly and ensure obtaining the optimal solution as a whole for population development，seeking balance and entire convergence．The optimal design of the trusses structure of the railway station canopy is made with the optimal design model for 3 D trusses and matlab software．The result shows the adaptive genetic algorithms is an ideal optimal design method for building structure．

Research conclusions: Through analyzing the reasons for setting the successive route for 6‰descending grade and the sophistication of the braking capability and control equipment of the train running on passenger dedicated line，the idea is expressed in this paper that it is unnecessary to set the successive route when there is a 6‰ descending grade on passenger dedicated line．This idea breaks through the regulation of The Chinese Railway Specifications，but has significance to decreasing the investments in the railway track and signaling equipments，reducing the land occupation and enhancing the traffic capacity．

Research conclusions: From the study on the development and design of reserved top—head platform of Shenzhen Qianhai Subway Car Depot，it is concluded(1)The design of reserved top—head platform of Car depot for fire protection should be made in accordance with the real condition of each building and the suitable measures should be taken to meet the requirements of fire protection．(2)The problems in the fire protection of Car depot should be overcome by adopting the current technologies for fire protection with the Security Code and Standard．(3)The heat insulation measure with fire—proof coating should be taken or the protective layer for the members of the beam and plate should be thickened to meet the requirement of 4—hour fire resistance and the construction demands．