Journal of Railway Engineering Society

Research methods: By using system engineering method, the paper analyses the existing transport corridor planning one by one, studies on the characteristics of southwest railway network, and uses techno-economic comparison method to demonstrate Sichuan southerly transport corridor plans.

Research results: It will benefit to the layout and development of southwest railway network form building a new railway which connects southwest area with Guangdong and Guangxi area, accelerate the economic and social development of relative area. It will also provide better development foreground to relative railway hub layout and passenger station layout of Chengdu railway hub.

Research conclusions: The conclusion is that Sichuan southerly transport corridor using Chengdu-Kunming railway corridor from Chengdu to E'mei, building double line corridor from E'mei to Guiyang pass through Yibin, Xuyong. It can arrive Liuzhou pass through Guizhou-Guangxi railway, arrive Guangxi pass through Hunan-Guangxi railway, and arrive Guangzhou and southeast littoral pass through Liuzhou-Zhaoqing railway. The south station in Chengdu railway hub acts as terminal station of passenger transport of Sichuan southerly transport corridor. The second passenger station of Guiyang railway hub needs to build Sichuan southerly transport corridor joining in.

Research methods: Considering the characteristic of passenger flow & function of intercity rapid railway and primary problem of socio-economic, cluster of cities and transport economic zone in this district, the main factor of the intercity rapid railway network is ensured.

Research results: There are large advantages about location and resource in the factors mentioned foregoing. With the development of these factors and economic, the amount of people who get round for business, tour and home will increase, and people will pursue for favorable and convenient trip, faster travel rapidity, comfortable trip condition, etc. The intercity rapid railway can satisfy people in these fields. There will be plenty of passengers among the district. And it will support the planed intercity rapid railway network.

Research conclusions: The forming and development of socio-economic cluster of cities and transport economic zone in this district is the main factor of the intercity rapid railway network.

Research methods: Railway project is considered complicated system in this paper. There are many ways on the primary review for main design factors on the system of railway line project. This paper studies the review way of design factors on the system of railway line project planned.

Research results: It is indicated that the design factors on the system of Chongqing-Huaihua railway line project are approving according to the conditions given by the Primary Review.

Research conclusions: It is one of the ways to forecast the goals planned by the owner of the project and has a foreground on development.

Research methods: Following the principle of" the route submitting to bridge site and the bridge site submitting to the geology for choice", the paper adopts the integrated prospecting methods for geology and discloses in detail the major engineering geological problems in the gorge area.

Research results: Through systematically researching geology and summing up the experience of route selection in geology of this project route selection, the author proposed the principle of "The site selection for the major project must be adhered to and the in macro areal geology must be attached importance to under the condition of complicated geological environment" and the issues must be paid attention to in survey and design. Finally, the proposal of bridge site and route with better engineering geological condition was determined.

Research conclusions: As the Qujiang gorge section for the Yumeng railway passing lies in the highly-intensive seismic area, active fault zone nearby and the internal and external dynamic geological disaster is quite remarkable. So it is difficult to choose the site of Qujiang Major bridge-major control work. Nevertheless, the engineering technicians have committed themselves to perform a comparison and research of the local geologic environment and principal engineering geologic problems of 8 bridge sites and 4 route proposals. Finally they determine the C2K route proposal of 5# the bridge site and create the favorable condition for design and construction of project.

Research methods: The paper carries on the research combining distribution of collapsibility loess with construction drawing design of Shengchi-Lingbao section of Zhengxi PDL.

Research results: The line will pass through loess tableland, strath terrace, gentle slope and relatively stable ravine zone, avoiding through sink hole, gully side and slope zone where the gully is developed as possible. If passing through the collapsed loess regions, the line will pass through the regions where there is light collapsibility and good drainage condition on the ground surface. If the line passes across the deep loess gutter, in combination with landform the designed height will be lowered. When selecting the route, the subgrade-bridge proposal and subgrade-tunnel proposal will be alternated comprehensively.

Research conclusions: The route in loess regions with deep collapsibility will try to avoid passing through embankment. The section concentrated with the culverts will be considered to pass with bridges. And long cutting engineering will be avoided. The concave slope will not be designed where the entrance and exit of the tunnel as well as the underpass of the highway have already been set as possible.

Research methods: Based on the economic and natural conditions and engineering characteristics along planned Changshou-Dianjiang-Liangping Railway Line, the track scheme is optimized through making analysis of the design scheme of the run of railway line, design grade and track joining in order to save investment and coordinate the railway with other infrastructures.

Research Conclusions: A scheme of railway line is proposed with less line length, less amount of work and less investment through making research on the design of route selection. This scheme not only can coordinate the railway with other infrastructures and planned construction projects organically, but also can better meet the requirements of railway transport.

Research methods: The analysis which influences soil sample test indices with methods hammering core drilling and rotary drilling is quantitatively. And some test indices obtained from different geological units in Beijing area are selected and studied contrastively.

Research results: In accordance with the geological condition in Beijing area and geological properties along the purposed railway line, the hammering core drilling can be adopted as the primary work method in general geological layers. While in other strata, it can be one of the auxiliary methods.

Research conclusions: After the contrastive study of different samples with the two work methods, there is little influence in void ration, water content, liquid index. The compressive modulus is higher 15% in hammering core drilling. But, there is big influence index of soil testing in soft cohesive soil (IL≥0.75).

Research methods: The main research contents include: (1)the experimental research of dynamic characteristics of subgrade bed of ballastless track; (2) the experimental research of techniques against foundation settlement which focuses on pile-net subgrade and pile-plank subgrade; (3)the research of rationality of using red beds as fillings for subgrade of ballastless track; (4) the research of stiffness matching of under-rail foundation of ballastless track. In this paper design and construction of subgrade in comprehensive experimental section of ballastless track on Suining-Chongqing line based on the experimental research, three key technologies of ballastless track subgrade of passenger traffic special line are discussed, which include the control of foundation settlement, the longitudinal stiffness matching of under-rail foundation, and the rational use of not-fine subgrade materials.

Research Conclusions: The applicable condition and design method of pile-net subgrade and pile-blank subgrade, the design and application of bracing stiffness of subgrade surface, and proposals for rationally using the not-fine subgrade materials are presented.

Research methods: First smash the filling of red rock to less than 2 mm and increase the compactness of sample to 95%, then make step-by-step single axle loading on the sample until the sample damages. The duration of loading for one step is about one month. At the same time, fit the reduced section of creep curve with K-K-H model based on the test result of creep curve by step-by-step loading, and predict the post-completion settlement of the embankment with 10 m high filling by adopting numerical simulation according to the fitting result.

Research results: It is known from the result of numerical simulation; the post-completion settlement of embankment top as 4 mm for one year and embankment top is in stable status about 40 days.

Research Conclusions: The result shows red rock as filling can meet the requirement of post-completion zero settlement for embankment after it is treated by construction technique.

Research methods: Based on multiple and beam theory, stress module of foundation under ballastless track in turnout area is established with finite element method. The paper analyzes the foundation stress under ballastless track in turnout area in the light of the feature of contact condition of ballastless track slabs.

Research results: Under the same load condition, the tensile stress of ballastless track slabs without close connected is bigger than that of slabs with close linkage structure. When it is closely linked between slabs of track, whether the track slabs connected or not, it influents little on the press-stress of track slabs and the bending moment of subgrade surface.

Research conclusions: Established finite element model of ballastless track in turnout area, analysis has been done to the track response under trainload action of under ballastless track bed in turnout area. It also analyzes and calculates the maximize bending moment of track slab cross section of independent and continuous track bed in turnout area which gives reference for the design. There is little influence on the press-stress of track slabs whether the track slabs connected or not, so it should make reasonable selection according to the characteristics of independent and continuous track bed when design track bed.

Research methods: By using Finite Element Model, the paper analyzes mechanics performance of each layer of slab ballastless track and top-layer of subgrade bed under various working conditions, such as slab ballastless track on rigid subgrade, soil subgrade, inserting HGT layer or not below supporting structure, aligning the expansion joints between track slabs and supporting structure or not, and so on.

Research results: It is not necessary to insert the HGT layer below supporting structure. And if the expansion joints between track slabs and supporting structure do not be aligned, it is advantageous to track structure bearing force.

Research conclusions: On the rigid subgrade and soil subgrade, it is not necessary to install the HGT layer below supporting structure. When designing the slab ballastless track on soil subgrade, the number of expansion joints of supporting structure should be cut down as fully as possible, and the expansion joints between track slabs and supporting structure do not be aligned. When designing the slab ballastless track on rigid subgrade, determining whether the expansion joins is even or not. Under the same conditions, there is very low change of stress of each layer of the slab ballastless track when the thickness of top-layer of subgrade bed is increased from 400 mm to 700 mm on soil subgrade.

Research methods: According to the real situation of Houma-Yuncheng section and in combination with the research achievements at home and abroad and current state codes, the subgrade slope and drainage were designed specially based on the analysis of the geological, topographical and hydrological conditions and the integral comparisons of technology and economy. And the new loess subgrades with various collapsibility were treated using different measures, such as mechanical roller compaction, heavy tamping consolidation and dynamic compaction etc.

Research results: A set of successful design experience and a series of technical researches were presented.

Research conclusions: The results of construction experiment and traffic practice proved that the treatment methods used for the collapsibility new loess subgrade in this expressway were reasonable and feasible. Moreover, the treatment methods also provided valuable experience of subgrade design and treatment for this area or those with the same type of loess in future.

Research methods: The research was made on the features, types and computing method for the temperature field of cable-stayed bridge in this paper. In combination with the construction practice of Yunyang Yangtze Bridge, the space model was established by adopting finite-element method and the effect of temperature was calculated with model, and calculation result was analyzed and compared with measured value.

Research results: The regularity of internal temperature field of structure was analyzed in this paper. The result showed uneven temperature difference of sunshine and so on had large effect on the structure of cable-stayed bridge, and proved the result obtained by this method was rather identical with the practice.

Research conclusions: The temperature effect on control of construction of cable-stayed bridge could be calculated correctly by the method presented in this paper, which was helpful for adjusting the line figuration and stress of main girder so as to make them meeting the requirement of reliability.

Research methods: By analysing the disserve caused by the lightning strike and the failure of the OCS, and referring to earthling concepts and related codes in both developed countries and China, this paper proposes the necessary and concrete measures of using general earthling on the ballastless track bridge of the passenger dedicated railway line.

Research conclusion: It is necessary to make reliable electric connection between the abutment of the bridge and the general earthling system in the section of the viaduct. Based on the character of passenger dedicated railway line in China and in order to avoid effect to the signal track circuit and meet the needs of short-circuit protection of traction power supply system, we set section (about 100m) with earthling reinforcing steel bar in ballastless track board and make each reinforcing steel bar connected to general earthling system in its own section. Now, this measure is applying in ZhengXi passenger dedicated railway line.

Research methods: According to the part of crack in the pier, the paper erects finite element analysis model of the pier, analyzes the space stress of the pier structure under dead load, live load, inner and outer temperature difference, concrete shrinkage and drops in temperature, et. According to the analysis result, the worst-case load combination situation makes sure the reason of the crack.

Research results: Pier concrete surface max tensile stress caused by concrete shrinkage and drop in temperature or heat of hydration is much greater than the split total stress of the dead and live load and exceed the concrete tensile intensity. The main reason of the pier's crack is the stress of concrete shrinkage and drop in temperature or heat of hydration of mass concrete.

Research conclusions: The mass concrete pier construction of passenger transport special railway line can adopt these measures in design and construction.

Research methods: By autoptical work to several diseased concrete bridges, the paper makes experiments about their atmosphere, surface water and groundwater. According to the type difference of corrosive mediator, the paper makes analysis of physics, chemistry and structure.

Research results: For the concrete protective layer’ looseness, desquamation and rust-eaten of the reinforcement, the paper makes sure the cause, provides strengthening and reforming measure for the diseased bridge and makes suggestion for design and construction.

Research conclusions: By air and water, through concrete's crack and capillary porosity, corrosive matter diffuses and reacts with some matter in the concrete, makes damage to the structure. The disposal of the diseased concrete bridge includes enhancing the concrete indensity and waterproof impermeability, and stain resistance of the reinforcement. It has significant meaning to prevent from disease, lengthening the life of the bridge.

Research methods: With the background of work experience of the author himself on Bapanling and Changliangshan Tunnel, the important role and significance of geological forecast on construction of long-large tunnel in railway, high-way and urban rail transportation in China are emphasized in this paper.

Research results: The planning, objectives, contents, methods, outcome's form, schedule and the conclusion of the forecast are also summarized in this paper. And it pays more attention to introduce the methods of the forecast.

Research conclusions: Geological forecasting is an important link to tunnel construction. It should be brought into construction procedure so as to instruct tunneling and offer the scientific basis of tunnel construction.

Research methods: Arranging 23 geological drilling hole, choosing the acoustic velocity, the apparent resistivity, the self-potential, the bottom hole thermometer, the inclinometer five logging parameters and borehole televiewer to judges the rock layer, the paper uses the probability statistics methods to carry on the statistical analysis to the test parameters.

Research results: Different variable probability curve with different characteristics, the limestone, the fault breccia, the paste dissolve the breccia relative dispersion to be big, the possibility of large broken rocks to the construction influential. But the politic limestone and the granite-gneiss relative dispersion is small. And the rock has the stave probability to be small. Borehole televiewer is the most direct way to determine groundwater supplies relations.

Research conclusions: The method accurately makes decent the stave degree, the water-bearing stratum and the military supplies relations.

Research methods: The random traveling car flow in the highway tunnel is assumed to be constant and continuous. According to philosophy of momentum, energy and mass conservation, the relevant relationship is established to search after and the author analyzes regularity of airflow motion of natural ventilation in such tunnel.

Research results: Establishing and solving the quadric equation with n unknowns of wind speed in each subsection of tunnel and then other parameters can all be worked out.

Research conclusions: Under the premise that ventilation opening can be set, in the one-way traffic tunnel, this natural ventilation mode is also an effective ventilation proposal.

Research methods: First, the author collects relevant materials, and then investigates circumstance. In the end, the author sums up a suit of construction methods and quality master measures.

Research results: The article describes construction of single turnout, crossover, scissors crossing, such as, survey of basic sign, construction difficulty, construction process, construction scheme, construction quality master and construction equipment(including mini-jack).Then the author brings out the problems and relevant analysis.

Research conclusions: Urban track transit is a suit of systems engineering. Track transfixion is one great mark of urban track transit engineering completion. Turnout monolithic track bed is key to track engineering, so track builder should seize construction difficulty, adopt logical construction scheme, use advanced equipment, carry out staggered quality master program strictly and insure construction quality. And also, the people should plan as a whole; do former preparation and later cooperation well to insure construction quality.

Research methods: The paper contrasts analysis of integrated technology which will be carried out in combination with the city planning, circumjacent environment and structural system, etc.

Research results: Through the study for topics on the elevated bridge, station platform type, decreasing vibration and noise reduction, etc., this paper researches the design experiences and relative technical measures for elevated line of urban rail transit.

Research conclusions: For the type selection of elevated bridge of urban rail transit, in addition to meet the strained requirement of structure, it is also considered unitedly in combination with city planning and cityscape. Generally, the box girder is selected. For the type of elevated station platform, considering operation and mass, etc., the island platform is selected generally. For the decreasing vibration and noise reduction of elevated line the integrated measures are adopted on these aspects, such as structure, track and acoustic barrier, and so on.

Research methods: By comparison on such fields as technical features and ridership of Inner-city rapid rail transit system, intercity rail transit system and urban rail transit system respectively, the analysis of differences on function orientation and technical features are performed. And by using of reference of experiences on development of inner-city rail transit system both at home and abroad, criteria and technical standard for planning of inner-city rail transit system are proposed.

Research results: The facts on features regarding ridership and technical standard of Inner-city rail transit system lies in between those for intercity rail transit system and urban rail transit system. Therefore, technical standard as proposed is closer to those for urban rail transit system.

Research purpose: In order to ensure the healthy and orderly development of Inner-city rail transit system in China, preparation of planning for multilevel and multimode transport within administrative regions is enhanced. Besides, interactive coordination of each districts and towns is also enhanced in connection with transport planning for the purpose of integrating the multimode transport within its regions which fully plays its roles in connection with function and efficiency.

Research methods: In the aspects of system constituting, calculation in result, ventilated engine room and equipment's arranging, contrast method is adopted to precede the comparison. At the same time, the aspects of the working expenses, the constructing price and early investment in equipment are compared and analyzed. The author made a technique economy comparison and analysis.

Research results: From this paper, we know that the shield system is less than the open /shut ventilated system in the working expenses. On the early investment, include the early investment in equipment and construct price, the shield system saves to invest more one million Yuan.

Research conclusions: Only as far as the air condition and ventilated system is considered, whether on the early investment or in the working expenses, the shield system has greater advantage than the open/shut ventilated system in Tianjin. Further confirmed, it is available that air condition and ventilated system was changed from the open/shut ventilated system to the shield system during the first step designs of Tianjin subway No. 2 line.

Research methods: Through studying of two reforming examples of existing routines regarding Erweilu Station of Tianjin Underground Routine One and Tobacco Factory Station of Period One of Haerbin Underground Routine One, this paper further researches and discusses problems in existing routines one by one.

Research conclusions: From the above two different examples of reforming of existing station, we can reform and utilize existed routines based on the guide principle of “utilizing section, reforming stations". Due to the comparatively easy disposal in section tunnel, it is easy to reform. As stations serve passengers directly, in which equipment are gathered together, it is difficult to reform. Rebuilding stations not only can improve underground service quality but also can solve the technical insufficiency of existing station completely.