Journal of Railway Engineering Society

Research methods：Based on the study and understanding of the major engineering geological problems of the Yunnan- Tibet Railway, firstly the geological route selection method is adopted to confirm the preliminary mute strike. Afterward, comprehensive argumentation and selection will be carried out by combining the technical conditions, important economic locations and its catchement areas, development of natural resource etc. to select the beat mute scheme.

Research conclusions：The Yunnan-Tibet Railway is located in the area of the most intensive new tectonic movement in Southwest China, where geological hazards are active along the Line. The major engineering geological problems include active faults and earthquake, high stress, earth heat (geothermy)，hazardous gas, collapse, landslide, mudflow, glacial action, snowslide , karst, soft soil, frozen soil, swelling rock (soil)，drift sheet, sand storm, sand soil liquefaction, radioactivity etc.and therefore the area may 6a called”The World Geological Museum". Compared to the completed Baoji-Chengdu Railway，Chengdu-Kunming Railway, Manning-Kunming Railway and Qinghai-Tibet Railway, the Yunnan-Tibet Railway will be of far more complex engineering geological conditions, far more difficult in reconnaissance, design and construction; therefore, it is named ”The Toughest Railway Project Worldwide"，To solve the problem of the route strike of the Yunnan-Tibet Railway, the "Dali-Lijiang-Deqin-Linzhi-Langxian-Lhasa" scheme is recommended. As for the construction time sequence, the east and west sections will be constructed before the middle section, so as to reduce the state's heavy burden on investment in the project.

Research methods: Based on the system theory and control theory, the rational survey program is worked out, the rational survey method is selected, and many methods are adapted for the important objects to snake comparisons. In this paper, the method and technologies used for surveying geological conditions in this section are summed up.

Research results: The surveying work was complete in 2005 and the survey achievement has been appraised.

Research conclusions: The construction of about two years shows the result of geological survey conforms to the real geological conditions.

Research methods: According to the geologic and landform feature of the section with karat collapse occurred during the construction and operation of the raising speed renovation project of Zhe-Gan railway Iine , this paper analyzes the occurring cause of karst collapse, integrates the karst prospecting data and construction regulation effect. And combining with karst regulation experience on other railway lines, the discussion on karst regulation principle has been carried out.

Research conclusions: The karst ground collapse regulation scope on high speed railway shall be expanded to the section prone to collapse with the thickness of earth surface cohesiveness less than or equal to 20 m ( absolute thickness ).The line shall adopt the bridgework for the serious karat collapse section with large pumping demand. During karat regulation construction, the combination principle of prospecting and grouting must be carried out, the regulation scope and depth as well as pressure grouting parameter and technology shall be adjusted as per the actual condition to realize the purpose of controlling karat ground collapse.

Research methods: Soft soil foundation reinforced with dry jet mixing pile and crushed stone pile are research subject in this paper. By comparing the theoretical calculation and monitoring data, the subgrade design methods are corrected and developed.

Research conclusion: It is feasible and economic that the soft soil foundation of Suining-Chongqing railway is treated With dry jet mixing pile and crushed stone pile. Passenger dedicated railway railways which targeted speed is 200 km/h and higher than 200 km/h is should be designed according to the settlement after construction. Total settlement of the soft soil foundation treated with dry jet mixing pile and crushed stone pile is made up mainly by the settlement occurred in the course of construction. The rate of settlement of compound foundation achieve maximum value half a year after construction, and then it decreased.

Research methods: According to the utility function, the yard is partitioned reasonably，also design loads，surface type and settlement controlling standards are determined. Based on geological and hydrological condition, in addition to scheme of yard foundation strengthening is studied, proper engineering measure and test demands are determined.

Research results: The testing results are fine after strengthening the yard by vacuum prepressing, cement deep mixing pile.

Research conclusions: Vacuum prepressing can improve the mechanics condition of the foundation, eliminate harmful deformation. The method is suitable for saturated soft clay foundation, especially when the natural moisture is high or erosive ground water or thick soft clay. After treatment, caustic dross can beused as fine foundation making good use of offal which has good economic benefits and social benefits.

Research methods: Based on the vehicle-track coupling dynamics theory, the vertical dynamics model of vehicle and track on the embankment had been set up, and the computer program is worked.

Research results: The dynamics responses is obtained regards on different working condition, and the asymmetrical settlement influence law on the wheel/rail dynamic system is researched too.

Research conclusions: Analysis results indicate that the wheel/rail system dynamic interaction increased sharply when the vehicle passing over asymmetrical settlement, the dynamic stress of CA layer and embankment increased also. The a- symmetrical settlement suggestion value should be limited to under 20mm-30 mm/20 m with speed of 250 km/h, then the asymmetrical settlement suggestion value should be limited to under 20 mm/20 m with speed of 300 km/h.

Research methods: We established a element model of the seamless turnout on continuous bridge and used the ansys soft to resolve this problem and make a analysis on the Parameters Influences.

Research results: The calculation results show that the setting style of seamless turnout and the disposal of supports are important influential factors and the greater fastening resistance and ballast resistance are propitious to control the displacement of the seamless turnout .The calculation results also prove that adding the stiffness of the pier can improve the displacement of the seamless turnout the additional stress of the rail. The amplitude of rail temperature's variation has a very important influence to the force and displacement of the system. The rail stress-free temperature should be set reasonably.

Research conclusions: We should avoid setting the seamless turnout on the sides of the beams and design a reasonable Fastening-down temperature of rail to reduce the force of system.

Research methods: The historic contributions to design and construction of grand bridge made by the innovative technologies applied in design and construction of Wuhan Yangtze Grand Bridge are revealed through reviewing the process of design and construction of the bridge.

Research conclusions: Wuhan Yangtze Grand Bridge has been tested in its quality for 50 years. It shows the piers never subside, the rivets of master truss of steel girder never loose, and the plane and vertical types of line and arch angle never change. The innovative technologies applied in design and construction of the bridge have been extended since then for 50 years, which have brought great achievements in design and construction of railway and highway bridges.

Research methods: Aiming at natural conditions and distribution of bridges and tunnels, systematic analysis has been done from aspects of technical feasibility, economical rationality, construction period, the structural form of box girder and so on.

Research results: Eight feasible schemes have been proposed, and combining with the practical situation of the engineering, schemes such as adding construction and receiving yards for girder structure, casting-in-situ the integral box girder, post concreting for partial flange plate of integral box girder, etc. have been adopted in order to meet the requirements of the engineering construction.

Research conclusions: The construction of simply supported 6oz girder in bridge-tunnel connection section on passenger dedicated line can be chosen by comparing various schemes synthetically such as adding construction and receiving yards for girder to avoid increasing the section of the tunnel for the transporting of the girder through it, casting-in-situ the girder, replacing integral box girder with twin-piece composite box girder, replacing integral box girder with multi-piece type box girder, post concreting partial flange plate of integral box girder, building access road to avoid the tunnel for transporting the girder and replacing concrete integral box girder with combined structure or long span concrete bridge, etc.

Research methods: Aiming at the problem that crack often appear; an the end side of box girder for railway passenger dedicated line, the analyses of the cause for crack are made through adopting finite-element computing method and the issues for attention in construction control of box girder are presented.

Research conclusions: The following proposals，made:(1)It is necessary to adjust the construction order involved in Pre-stress and avoid stretching the drill ways of N2a and N1b as much a possible while pre-stretching and primary stretching，conducted; (2) It is necessary to well control the elevation of girder bearing bed and observe the uneven subsidence volume of the bed on fixed time, and if necessary, the measures should be taken so as to avoid appearance of movement of torque; (3) It is necessary to reinforce the structure around the girder lifting hole to avoid appearance and extension of cracks around the hole caused by the large stress while lifting and moving girder, and take some mearsures for keeping the even self weight effects on both ends of girder body w avoid appearance of movement of torque while lifting, moving and lowering the girder.

Research methods: Taking the Tangjiadu-Fujiang Double-track Railway Bridge in Dazhou-Chengdu Railway and Sanhuizhen-Qujiang Triline Railway Super Major Bridge in Xiangfan-chongqing Railway for example, this paper researches the lateral analysis and calculation of box beam by using MIDAS.

Research result: Through analysis of the examples, this paper provides the results that when the lateral prestressing tendon is set in top deck, the moments of top deck and the top of web would reduce obviously, while the moment of bottom slab would increase sIighly , the top deck would he in compression and the tension stress of bottom slap would increase slightly.

Research conclusion: This paper concludes that it is beneficial to set the lateral prestressing tendon rationally in top deck. But if the lateral width of the top deck is not too wide and the height of the top deck is not restricted, the lateral prestressing tendon ire top deck need not be set.

Research methods: Based an the complicated geological conditions and the design requests of the tunnel, all investigation methods involving application principles, job contents, quantity of work and effect，introduced detailedly.

Research results: The results show that karst and groundwater do not developed, and severe geologic hazard-water gushing, projecting mud soil, rock burst, harmful gas etc. will not occur. Except that engineering geological conditions of 4. 5 km long gypsum 6reccia and partial fault crushed zone，relatively poor, the others are good. Now the construction of funnel goes well and prominent technical, social and economical benefits are obvious.

Research conclusions: In the survey of the long tunnels which have complicated geographical and geological conditions, the comprehensive investigation plays a key role far the entire process of geologic investigation of tunnel, with the geology investigation taken firstly, the macroscopic function of remote sensing developed, the physical exploration as well as the further validation with drilling adopted effectively.

Research methods: Base on the No. 2 line project of Tianjin metro, this paper calculates and analyzes the data by plane FEM, and studies on the similar projects inland by analogy.

Research results: The potential risk of horizontally approaching excavation shield tunnel is discussed. The study elicits the internal force and deformation of the structure, and the distributing character of them, and the sedimentation curve fore-and-aft the approaching tunnel excavation, the secure construction scheme is established.

Research conclusions: The strengthen scope of the earth around the tunnel should be extend in horizontally approaching excavation shield tunnel，and isolating pile measure should be adopted between tunnels, meanwhile in the construction process, the construction parameters should be strictly controlled, and monitoring should be enhanced.

Research methods: The economical and feasible signaling scheme should accord with the correlation standards and the extension of track's effective length design for complex station yard.

Research results: According with the special design of station yard and electric interlocking standard, this paper mainly introduces a special signalling engineering design of two starting signal for one line circuit.

Research conclusions: During the innovation of existing line for enhancing traffic capacity, the lengths of partial tracks can be prolonged under the condition of difficultly conducting innovation and other special conditions by setting the signal into double departure way. Application of a special signal structure with additional blue light indication of departure signal and adopting a special signal indication and mute setting way can basically satisfy the traffic requirement and reduce the modification of the existing circuits as much as possible. Addition of train terminal circuit and modification of signal lighting circuit can guarantee the safety of train route and shunting route.

Research methods: The research is developed from the point of view of station location, station layout, station area planning, and expounds research content by the example of new Chengdu railway station.

Research results: This paper presents the principles and methods of newly-built station location selecting of intercity railway, expounds the key points of station layout，discusses the planning problems of station area road planning, traffic joining, transfer designing.

Research conclusions: ln the planning and designing process of intercity railway newly-built station, the needs of urban transport and railway passenger sport should be comprehensive considered, and urban transport and railway passenger transport should 6e coordinated developed based on optimization of station layout and station area planning.

Research methods: Based on the conditions that different types of railway lines will be connected to stations, the flexibility in design of railway station should be enhanced, even though there are so many restrictions. There is a conclusion of station design's technique in this paper.

Research results：The problems of junction station can be resolved by designing some curving tracks with small deflective angle correctly.

Research conclusions：We can choose different types of curving tracks with small deflective angle, according to different practical conditions.

Research methods: In view of the growth of international monorails, especially the development of Japanese monorail which applies extensively in public transportation, along with its technique introduced to China, this paper draws the overall conclusion of route design, by taking into account the criteria of mute plane and profile design in straddle type monorail construction in Chongqing city.

Research Conclusions: This paper refers to relevant technical summary of Japanese straddle type monorail. And based on the application of such design in Chongqing City, it proposes route plane and profile design criterions, imperative factors for various mute patterns and suggestions about problem solutions, management enforcement and optimal designs.

Research method :According to the analysis of comprehensive transit mute network of key airport at home and abroad， making contrast analysis of technical and economic from the investment, the volumes of passenger and comprehensive evaluation, and raise three design projects that use existing airport railway running inter-city trains, build a new light rail leading into the air harbor, and build a new airport special railway line.

Research results :We recommend to the plan of build a new light rail. This plan has characteristic of scientific and reasonable structure, fully and complete function. It is a comprehensive transit system that may quickly link up external tansit and have a good transport for passenger.

Research conclusions: Bulding the rail transit of the Kunming new international airport will improve transit structure of eastern developing axis at Kunming city, and sole environment problem of transit crowd and city pollution. It is the necessity for developing the urban transport of Kunming.

Research methods: This paper investigates the existing domestic urban rail transit, the condition of the rail fastener and turnout, analyzes the sticking point and harm, studies the solution methods and measurements.

Research results: The standardization of the track facilities of urban rail transit is imperative. According to the present situation, it could be divided into three steps: simplification, standardization and serialization. Aimed at the trend that special turnout is asked for to meet the demand of urban rail transit, some schemes for standardization must be brought forward as early as possible.

Research conclusions: The first step is to control the quantity of railway facility types to the present condition, and new product will not be developed no longer. Some products that the ratio between performance and price is more reasonable will be chosen, its design will be optimized, then they will be made as the standard figures or universal figures. In addition to meet the requirements of different project condition, there must be some series products for different specification. The standardization must be attached importance to and intervened by the upper interrelated department and the power to examine and approve the standard figures; perfect the process of examination and approval, then the standardization would be realized well-off.

Research method: Aiming at compose of subway ventilation and air-conditioning system and device, it analyses the main subway noise source and denoise noise elimination equipment choice in site measurement data.

Research results: Subway ventilation and air-conditioner is one of main noise source. Noise elimination denoise equipment responds to the request satisfying acoustics，aerodynamics，processing aspect

Research conclusions: The ventilation and air-conditioning system asks a subway to adopt rational denoise of science noise elimination measure. Dyadic impedance movie deadener can carry out effective controlling on noise and eliminates.

Research methods: This paper analyzes differential current transducer function and circuit principle used in high- voltage board circuit of localization type A metro vehicle, then introduces its outline structure and material features and performance.

Research results: By application of differential current transducer in the field test for Guangzhou Metro Line 1，this paper proves the differential current transducer with reliable and stable working performance.

Research conclusions: By making Geld test of magnetic modulation type differential current transducer in Guangzhou Metro Line 1，which proves whose leakage current test accuracy can reach shove t 10%，with high immunity to external interference. Compared with other type current transducer, magnetic modulation type with remarkable advantage, can adapt to the requirement of traction inverter in localization type A metro vehicle,

Research methods: Combining the work of engineering geological investigation supervision in Wuhan-Guangzhou passenger dedicated railway line, such supervising methods as patrolling in-situ, sampling test and standing aside， adopted, the content, key points and quality control measures in railway geological investigation supervision are analyzed and summarized.

Research results: Key points and principles to control the quality of passenger dedicated railway line geological investigation supervision are put forward, effective work methods，proposed.

Research conclusions: The key point of the work is set on the quality control of geological investigation in situ. The principles such as inspecting and guiding in situ, strict management of geological investigation quality, and regular examination of laboratory，persisted in. Management in situ, testing and sampling, report censoring during the process of investigation are controlled as key points.

Research methods: This paper analyzes and recognizes the risk factors and find out the risk sources through features in each tache and different participants during the subway design construction, and then analyzes the reason focusing on each risk origin. Ai last, it proposes different risk countermeasures according to the features of different risk origins.

Research results: During the process of subway design and construction, risks keep in step with the course of engineering construction and there exist different risk factors in each course. Therefore, prevent and elude risks shall start from corresponding features of risk factors in each stage，perfect design and construction to achieve the aim of eliminating and reducing risks.

Research conclusions: Construction professional designers should not only solve the problems related to the special techniques by themselves, but also understand the basic concepts and contents in many other technical fields regarding to the subway station in order to strengthen general ability in coordination. Meanwhile, the design venture should be effectively reduced combining with current analysis design condition.