Journal of Railway Engineering Society

Research methods: Based on one loess landslide of a high embankment of Baoji-Zhongwei Railway, the exploration is made on the method of determining the location of slide face through comprehensive consideration of the liquidity index, elastic index, water content, joining face between fresh and old soils, slope crack and bulging control spots. Based on the data of survey, the most unfavourable slide face can be found out through forming a series of fold lines with the different formulas, determining arc slide faces of every group with the slope crack and bulging control spots and making analyses of single element and multiple elements.

Research Conclusions：The construction practice of adopting anti-sliding pile based on the calculated pushing force of the most unfavorable slide face shows this analysis method is feasible for the homogenized soil body which had a small wriggle and deformation without obvious overall displacement and was difficult to determine the position of sliding face with the complicated surface phenomenon.

Research methods: Based on the site geological survey information about water bursting of Cangling Tunnel, the concrete analyses are made for the scale , location , causes and geological conditions of water bursting and the explorations are made on the characteristics of composite of surrounding rock, geological structure, modern structural stress field and underwater from the view of geological engineering point in order to seek the regularity of water bursting and better treatment.

Research results: Water bursting in Gangling Tunnel is controlled by the geological conditions in the zone. Although tuff is not dissolved in water, but the special structure formed under the effect of modem stress field provides the passage and stored area for the underwater. This is the main cause for water bursting. Therefore，the geological prediction in advance system with TSP-203 and relative marks for it should be established and relative measures should be taken with the principle of ”Drainage first and grouting block second".

Research conclusions: For the soil and water disasters occurred in tunnel, first, the research should be done on the engineering geology，then the prediction and treatment should be carried out

Research methods: Basing on the actual pumping test data measured in the field, inversion-analysis program is used which is based on the genetic algorithms to identify the hydrogeological parameters. The results obtained by genetic algorithms and two-pointes method are compared.

Research results: The results have indicated that two kinds of parameter inversion method can get the similar results.

Research conclusions: As one kind of optimization methods , the genetic algorithm is simple , universal and also has the characteristic of good adaptability and high efficiency on parameter inversion, and which can be widely employed to hydrogeological parameter inversion.

Research methods: Combining with the experimental engineering of the improved expansive soil of chase slope with medicine in the railway test project, this paper discusses the mechanism and effectiveness of improving expansive soil, compared analyzes the physical and mechanical propertyes and swell-shrink characteristics of expansive soil fore and improved, and studies the improved scheme of expansive soil. Some availability conclusions are provided for the design and construction of expansive soil slope.

Research results : It is feasible to use medicine to meliorate the expansive soil. The granule composing , physical and mechanical propertyes and swell-shrink characteristics of expansive soil with meliorative medicine are obviously ameliorated. And the mechanical strength and water stabilization is also improved.

Research conclusions : The enginerring character of expansive soil is ameliorated very much. The meliorating depth of the chasm slope is about 80 cm to I00 cm. If the depth is exceeded I m, the effeciveness of improving is not good and the optimal time of chemical melioration is 3 to 4 times.

Research methods: Through the construction practice of filling the underground corridor of Beijing Olympic Park with bubble mixed light soil, the inductions are given to the basic characteristics of bubble mixed light soil, design of filling soil for reduction of load , parameters of mixture ratio , key techniques , quality control and test technology , and the analysis is made for the tested results.

Research results: It has a good result to use bubble mixed light soil for reduction of load. Although the volume-weight of the soil under submerging increases much，but it does not exceed the design range and meets the requirement of corridor design load.

Research conclusions : It has a perfect achievement to use bubble mixed light soil for reduction of load and has a wide applicable prospect and social benefits when bubble mixed light soil is used for filling surface lower foundation ditch, including filling soil to the area submerged by underwater.

Research methods : Based on the construction practice of reinforcing weak soil composite subgrade in the experiment section of Wuchang-Guangzhou Railway Passenger Dedicated Line, the systematic researches are done on application of strong tamping and its replacement technology in reinforcing subgrade of passenger dedicated line from the fields of selection of construction method, design of technique procedure and quality control according the engineering geological conditions.

Research results: Taking the performances of construction machinery and geological conditions into account, the tests of strong tamping and its replacement technology are done in the different typical areas in Wuhan Experiment Section and the comparison and analysis are made for the tested results before and after strong tamping to determine the its applicability for Wuchang-Guangzhou Passenger Dedicated Line under similar geological conditions, improve the construction technique，sum up its experience and lay down the technical parameters and test methods. The practice shows strong tamping and its replacement technology are feasible for reinforcing subgrade with satisfying the requirements of bearing capacity and design deformation and better control post-construction settlement.

Research conclusions: Tamping capacity is an important index of reinforcement depth for using tamping and its replacement technology. It needs rational interval time to use strong tamping and its replacement technology for reinforcing clay soil, especially for saturated clay soil. Strong tamping and its replacement technology are suitable for reinforcing the composite subgrade of passenger dedicated line.

Research methods: The analyses are made for the various factors influencing the precision of rail support platform and the effective measures for precision control in the courses of the manufacture，installation and test.

Research results: The requirement of precision control of rail support platform for track-bed template has been met through precision control and adjustment of the installation planes of the platform and template and their locations.

Research conclusions: After precision control of rail support platform for ballastless integrated track-bed template, it needs less grinding for ballastless integrated track-bed , which not only meets the requirement of construction schedule , but also reduces consumptions of toll and electric power and the manufacture cost.

Research methods: The analysis method of the strength and rigidity is adopted for reinforcement system and the on-bridge test method is adopted with theoretical calculation and testing train.

Research conclusions : The analyses show the reinforcement system is suitable for jack-in construction of frame bridges with different spans, widths and axial lengths and the tests show the reinforcement system is safe and reliable under condition of train speed limited to 45km/h. This reinforcement system will be safe and reliable for higher speed if some improvements are made，so it is a good way for jack-in construction of bridge of existing line and worth being used widely.

Research methods :For a long-span cable-stayed bridge , the vibration-suppressed effectiveness of active control, semi-active control and passive control for the floating cable-stayed bridge is calculated and analyzed with its finite element model. Influence of seismic traveling wave effect on the seismic responses of cable-stayed bridge is analyzed.

Research conclusions: Semi-active control and passive control can get good control efficiency for the most seismic responses of the cable-stayed bridge, but they can make some seismic responses including bottom shearing force of the bridge tower lager. The seismic inputs with different frequency spectrums eviden街influence seismic responses of the cable-bridge and vibration-suppressed effectiveness of the control methods. Traveling wave effect can make bad influence on the beam of cable-bridge, but can be propitious to bridge tower. Bad influence of the 3 control methods on vibration-suppressed effectiveness is little.

Research methods: The analysis is made for the influence on historical building-Luci Former Residence by construction of Wuhan Yangtze Tunnel with numerical value simulation method, large-sized finite-element software and numerical value analysis model.

Research conclusions: The differential settlement is the major factor influencing the stress distribution and its max. value on Luci Former Residence, and the value of differential settlement makes big influence on the stress distribution and its max. value，so the differential settlement should be controlled strictly and its value should be reduced as much as possible in construction.

Research methods : The analysis is made for karst strata by adopting many integrated survey ways and the construction program is optimised through making comparison of the programs according to the characteristics of shield machine and shield construction.

Research results : The successful construction of shield tunnel in karat strata verified the feasibility of the survey and reinforcement programs，which fills the blank in China.

Research conclusions: It is an effective way to detect the distribution of karat caves by adopting integrated survey method. All of the strata reinforcing program made with the characteristics of shield construction, the innovation of shield machine and the technical measures taken for tunnelling are suitable.

Research methods： By bulding up the sequences of space , dip-direction and dip, the parameters of chaotic features for three sequences can be obtained by calculation. Whether the sequence of discontinuities is chaotic one or not can be judged according to the calculation result. Besides, the chaos features of the sequence of discontinuities can also be judged by negative power in power spectrum and inclination in PCA diagram. Phase space could be reconstructed by embedding dimension and space delay.

Research results :Kolmogorov entropy is more than zero , lyapunov exponents tend to zero，correlation dimension is real number of more than 3，negative power appears partially in power spectrum in lower frequency and the FCA diagram as certain inclination. The calculatulon result of embedding-dimension-and space delay show that discontinuities could be spreaded into multidimensional space, and embedding dimension is suitable for being 15 to 19 and space delay for 2 to 6. Reconstruction of phase space represents puckering and distorting of its distribution.

Research conclusions: Discontinuities has chaos features when it presents space distribition located in chaos edge. The correlation dimension of discontinuities reflects the distribition situation of discontinuities like fractal dimention. It shows there is more discontinuity, the distribution is more complicated and the rock mass is more broken when the correlation dimention of space sequnce becomes larger. And it also shows the change of emerged status of discontinuity is larger and there is more directional preponderance when the correlation dimension of the sequnce of the same emerged status becomes larger.

Research methods : According to the specific geological conditions and the project design requirements of Jinshazhou Tunnel , the loading-structure model based on the finite element method is adopted to simulate structural stress of the lining structure for the design on three types of wall rock lining.

Research results : Through the numerical simulation，the external water pressure of lining and the stress distribution are got; the safety factor of the lining structure is checked. By analyzing the results of tests, the proper lining structure o, corresponding wall rock is selected.

Research conclusions : In the design of lining structure with full face latch-up hailing, the resist compression performance of before must be strongly considered. When the underground head is high in the region with vast groundwater, the external water pressure of lining can be lowed effectively by using drapery injecting plasm which can improve permeability. The feasibility that optimizing lining stress feature by control variance such as radius of invert external corner, radius of joint between invert and curve side wall, thickness of invert is examined and certificated through numerical simulation.

Research methods ： The engineering comparison and site experience were made.

Research results: Wuzhaoguan Tunnel were passed below through underground river successfully, by adopting the scheme of grouting interception and ponding to make undercurrent flow above the tunnel and by deep-hole grouting to strengthen the accumulation body. A serious of engineering measures were used, such as grouting at moving water state in the accumulation body, small pipe-proof protection，powerful support, short bench cut method, tunnel foundation root by steel-pipe pile grouting, etc.

Research conclusions：According to underground river engineering geological and hydrogeological conditions，this paper adopted the key technologies of”partition and sequence, mufti-joint pump，more slurry mix, rapid solidification and early strength"，effectively resolve the problems of the grouting closure and raising groundwater levels and tunnel excavation beneath the underground river accumulation in the rock-open-boundary conditions and high water flows rich state.

Research methods: Based on the many technologies of geological forecast in advance used in construction of A3 bidding section of Xiamen Xiang'an Submarine Tunnel, the explanation is given to the optional principles of the means and methods of geological forecast under different geological conditions.

Research results: The work of geological forecast is well done and the geological conditions are made clear according to the principle of” Using different technology to the different rock".

Research conclusions: The integrated geological forecast can 6e done and the distribution of sand layer and water content within 100 m range in front of the working face and the distribution of underground water within 15-30 m range in front of the working face can be made clear by adopting the technologies of TSP202 geological forecast in advance instrument , drilling hole in advance , infrared detecting water and geological sketch.

Research methods : Aiming at the problems to be solved , the further analysis is made for the working principle of intelligent lighting control technology, and the comparison and selection are made for the programs.

Research results: Under condition of no change of power distribution lines , individual lighter can be controlled and lighting system is changed from manual control to computer control, with achieving the best result of energy saving.

Research conclusions: The quantity of power lines and its cost can be reduced much by adopting monolithic computer technology and the system safety can be improved much. The solid relays of non-mechanical contact are used in control circuit for lighter, instead of traditional relays, with longer service life and easy maintenance. The intelligent lighting control system can be used in innovation of original lighting facilities.

Research methods : This paper adopts both qualitative method using questionnaire inquisition and quantitative method using QFD calculation.

Research results: Carrying out the content and mechanism of quality innovation in engineering projects construction, the management in an enterprise needs the new multiple quality management model which integrates the employee's quality behavior mechanism and complete quality management for the construction of labor-intensive project programs.

Research conclusions:(1)The key points of quality criterion innovation are as follows ; the detection rate of fault should be 99. 6% and the construction criterion should be made certain by both experts’ constitution and tests. ( 2 ) When the quality innovation rate of price , safety , maintenance and construction criterion , ui，is individually as follows: u1 =z ?/z1=3/3=1, u2=5/4=1.25, u3 =3.5/3=1.17, u4=5/3.5=1.42，we can get the competitive force C = 4. 07，which is better than its adversary in market demand fulfilling.

Research methods : Based on the practical experience of construction of Qinghai-Tibet Railway , the description is given for the management work of environment protection in construction from the areas of organization，rules and regulations and measures.

Research results: In the course of construction of Qinghai-Tibet Railway, a series of new and innovative measures are taken for environment protection to better control the biological influence on the areas along the railway by construction of railway，and the perfect achievement is obtained for environment protection.

Research methods: The approaches are to identify all the hazards associated with the activity of each process and type of potential accidents or incidents, to evaluate the Severity of Hazard and Likelihood of Occurrence, to determine the risk level. Based on the level of risk determined, risk controls measures should be selected to reduce the risk level to an acceptable level.

Research results: Risk assessment will be formalized to be the Inventory of Site Activities and Activity-Based Risk Assessment Form, which will become the guidelines for the site safety management together audited by the safety auditor, and also be the base to apportion relative responsibility of accidents.

Research conclusions: Risk Management crystalizes the safety management goal and controlling measures as well as promotes the site safety management efficiency and level, and it takes effectively precaution against the site accidents.

Research methods：Based on the bidding mode of railway commodity, the exploration is made on the causes of the problems from the areas of identification of tenderer qualification and the bidding mode for commodity controlled by Party A , and the legal status of subsidiary company of bidder is determined for bidding.

Research conclusions： In order to guarantee the bidding fair and just , the entity who has a specially economic relation with bidder is not allowed for bidding, otherwise there is probably a representative in the bidding commission. The price of commodity controlled by Party A is excluded in the total contract price in order to reduce the fund circulation times, bidding cost and project cost.

Research methods: Collecting the inside and outside materials which were used to make enterprise' s development strategy extensively, adopting the international popular judgment and analysis method SWOT at present, analyzing the competition advantages(strength)，competition inferior position (weakness)，the chance(opportunity) and threatening (threat) of enterprises, this paper drew the correct conclusion.

Research results: Within a period in the future, the large-sized enterprise have certain internal advantages in the market competition, the chance of external environment condition is very high, so the strategy that should be adopted is to take SO-increasing strategy as the core, cooperate with WO-turning back strategy, ST-pluralistic strategy of leading operation.

Research conclusions: The strategic objectives of enterprises are: increasing strategy-seize the opportunity, do large; turning hack strategy-improve the mechanism, do strongly; multiplex strategy-mufti-dimensional management, expand.

Research methods: The analyses are made for the drawbacks of traditional financial management in network environment and the explorations are made on the innovations of network finance from three areas, namely management mode, management method and management content.

Research conclusions: Realization of network finance needs join effects from many aspects. For examples, the electric trade，payment system and privacy issue need the support from the government , the organization structure and business flow involved in network finance requires the enterprise to innovate their organization structure and change views of the employees and realization of network finance needs the supports of network, computer and IT.