Abstract:To obtain the construction linetype of long span steel cable stayed bridges accurately, the paper presents a numerical simulation and control technique by taking geometrical nonlinear effects into consideration. Multiple short truss elements are used to model the sag effect of long cables. The simulation of multiple tensioning of long cables is realized by adjusting unstressed length of cables successively. Different activation modes for new generated components are introduced for different purposes that the tangent and parallel modes are suitable for construction process analysis, and the original position activation mode is used for the linetype control analysis. The sparse matrix algorithm is adopted to speed the simulation. The software of construction linetype control simulation for cable stayed bridges, BINAS, is compiled. The computational accuracy and the effectiveness are verified in the example of the Sutong Bridge.

Abstract:The prestressed cable AERORail structure is different from the common bridges, more fundamental experiments are required especially for its dynamics behaviors. Virtual prototyping technology (VPT) is an economical and timesaving way to study this new structure. After an analysis of the feasibility and the merit, this paper introduces the flexible model theory and method with VPT software. Based on the 1∶15 model experiment, the simulation process and skills with 1∶1 model are presented and the vertical displacement and acceleration time history curve is obtained. Finally, the paper presents a summary of the model skills for the flexible cable rail structure.

Abstract:Based on Timeshenko beam theory and stochastic imperfection mode, the stochastic imperfection mode superposition method was proposed for single layer lattice domes. First tangent stiffness matrix for Timeshenko beam was deduced. Then stochastic imperfection mode was set up with participating parameters of modes obtained by eigenvalue analysis. Then, a nonlinear stability analysis was made on single layer lattice dome with stochastic imperfection. And then the stochastic imperfection mode superposition method was proposed. Finally, an example verifies that compared with traditional methods, smaller samples are resorted to with the proposed method. The proposed theory and algorithm proves to be correct, effective in stability analysis of single layer lattice with dome stochastic imperfection.

Abstract:A progressive collapse resistance experiment was made of a two storey steel frame. The composite concrete slab was adopted and the action of the concrete slab was considered according to the theory of the composite beam during the design process. In order to simulate the instantaneous failure of the column, the horizontal force was implemented suddenly to the top of the column through a hoisting machine. Experimental results show that the test frame has enough redundancy because of the streghtening of the composite slabs. The composite beams have the higher flexure stiffiness because the composite slabs and steel beams work together through the shear studs on the top flanges. The columns and beams of the remainder structure do not fail further after the instaneous column removal due to the formation of the alternative load path. It is indicated that the steel frame with composite slabs has the higher redundancy and horizontal tie forces according to the present design method. The action of concrete slabs needs a reevaluation in the analysis of progressive collapse resistance.

Abstract:Investigations on the softening feature of post fire concrete was implemented in present research by adopting the bilinear softening traction separation law at room temperature. A new parameter λ, which directly influenced on the shape of softening curve, was introduced. According to initial fracture toughness and unstable fracture toughness determined by the wedge splitting method and the quantitative relationship among initial fracture toughness, unstable fracture toughness, and cohesive fracture toughness, the softening constitutive curve of post fire concrete was obtained through adjusting the parameter λ. It is concluded that the softening traction separation law obtained at room temperature with minor adjustments can also be applied to describing the softening feature of post fire concrete.

Abstract:Partially concrete encased composite girder with corrugated web was proposed to improve the structural mechanics performance of continuous girder under hogging moment. The bending behavior of concrete encased composite girders with corrugated web under two points symmetric loading was experimentally investigated. Experimental results show that the partially encased girder has superior bending strength and ductility compared to steel I girder, as local buckling of compressive flange is restricted by concrete encasement. In addition, prediction methods of bending strength under ultimate state were proposed based on the experimental failure mode and strain distribution. And the calculated bending strengths for steel and composite girders at ultimate state agreed well with the experimental results. The test findings and analytical methods were considered to be of special significance to the design of such partially encased composite girders with corrugated web.

Abstract:Natural soft clay tends to be anisotropy developed during deposition, one dimensional consolidation, and any subsequent straining. Anisotropy of clays affects its shear strength, stress strain response, yield surface declination, and so on. An anisotropic bounding surface model is developed based on Wheeler’s elastoplastic model (S CLAY1). The developed model is programmed in ABAQUS software by writing UMAT subroutine, which is integrated in return mapping algorithm. The developed bounding surface model is validated with undrained triaxial shear test of Kaolin clay. The study shows that the developed model can well simulate the stress strain behaviors and the change of excess pore pressure of normally consolidated and over consolidated clays. Meanwhile, the developed bounding surface model can also efficiently depict the initial anisotropy and stress induced anisotropy of consolidated natural soft clay.

Abstract:Under the theoretical frameworks of both the traditional fundamental diagram approach and newly developed three phase traffic theory, with regard to the characteristics of traffic flow based on detection data, traffic flow was splitting into three traffic states, which include free traffic , congested traffic and jam traffic. In the light of traffic states definition, firstly, traffic flow parameters of road network at the same instant is transformed to fuzzy information granulation which is made up by L, R and U parameters. Then, Elman neural network is employed to realize traffic states prediction with three parameters of fuzzy information granulation as inputting. Subsequently, traffic states composite index is calculated by the prediction result to identify the traffic states. Finally, the empirical researches proceed by taking a region in Beijing urban expressway network, the research results show that the proposed methodology can realize identification of traffic states variation in road network, the identification accuracy is 93.33%, however, the identification accuracy of SVM method on the same condition is 86.67%.

Abstract:Transportation network would be degraded under incident circumstance. If the change of demand side of the transportation system was not considered, the consequence of the incident would be overestimated. The demand vulnerability was proposed to evaluate the network’s ability to resist incidents by considering both the supply and the demand side of the system. A combined travel demand model and an accessibility measure based on the random utility theory were applied as the basis of the demand vulnerability index. A trial network presented the calculation of the index and its application for comparison of management schemes. The demand vulnerability analysis could be helpful for the planners and managers to take measures to enhance the network’s ability against incidents.

Abstract:Steel deck pavement is a world wide problem especially on special steel bridge.Based on the analysis on the construction problem and special requirements of steel deck pavment on the bridges with high lognitudinal slope and small turning radius,the paper presents a new kind of steel deck pavement,called ERS steel deck pavement.It contains three layers,such as Epoxy bonding chips layer(EBCL) and resin asphalt mixture(RA05) and stone mastic asphalt(SMA).EBCL is used as waterproof,bonding and antiskid layer,RA05 is used as an integrated layer and the SMA10 is used as a surface functional layer.Indoor test results show that ERS steel deck pavement has excellent performance and good workablity.The new pavement structure is used on the steel bridge connecting Hangzhou Bay Bridge with sightseeing flat.It solved the difficult problem successfully.

Abstract:This paper presents a new method for roadbed settlement measurement based on LabVIEW and .NET. Grating scales were used during the process and the data were transported periodically to researchers by E mail automatically for further analysis, estimation and application.

Abstract:The vibration reduction characteristics of steel spring floating slab track in metro viaduct were analyzed by the finite element method and field test in time domain and frequency domain respectively. The results show that the stiffness and distance span of the damper have a large influence on the top 10 order natural frequency distribution of floating slab, the variation of stiffness and distance span of damper control the vibration reduction effects of floating slab by changing the stiffness per unit length, the vibration level of roof, flange, web and the bottom plate of elevated girder decreased with 11~22 dB, 12~20 dB, 20~30 dB and 12~21 dB respectively in the range of 25~100 Hz when slab is lifted, the vibration levels reduction increases as damper stiffness decreases and as the distance span increases，the stiffness and distance of steel spring almost have no effect on the displacement of elevated girder. The floating slab track has a certain reduction affection on wheel rail noise in the range of 63~2 000 Hz.

Abstract:This study aims to improve the dewater ability and the stability of the activated sludge with the sludge production being reduced. The parameters, such as capillary suction time (CST), elemental compositions, distribution of organic matter molecular weights and Fourier transform infrared spectrum were investigated to study the influence of humus soil on activated sludge properties under the condition of thermophilic anaerobic digestion (at 55 °C). The CST results show that humus soil can greatly improve dewater ability of the sludge. The Mw/Mn of FAs isolated from activated sludge decreases according to the dosage of humus soil, and the micromolecular proportion raises from 50% to 70%. All HAs isolated from activated sludge show similar spectra with different intense absorbance during the region of 1 654, 1 540, 2 925 cm-1 which suggests that humus soil improves the aromatization degree and the stability of activated sludge. Similar results are also found in organic elemental and total organic carbon analysis.

Abstract:Production capacity scalability design is one of the major issue in reconfigurable manufacturing systems (RMS). Aiming at the problem of lack of practical production capacity reconfiguration methods, a production capacity expansion reconfiguration method of constrained RMS with characteristic of dynamics was proposed. First, based on an analysis of production capacity scalability theory, three kinds of fundamental reconfiguration methods were given. The RMS constraints models were constructed, and then, on the basis of cost models, production line smoothness index model, an integrated production capacity expansion model of RMS was established. According to the characteristic of the proposed integrated model, the implementation method was described in details. At last, a case was illustrated to verify the practicability and effectiveness of the given method.

Abstract:This work focuses on a capacitive micro accelerometer fabricated by micro electro mechanical systems MEMS technology, and the dynamics model between the detection characteristics of output performance (detection capacitance) and the microstructure is proposed. The calculation method of output performance of the accelerometer is presented. The analysis of the dynamics and detection characteristics of the accelerometer is achieved. To increase the output performance of the accelerometer, a structural topology optimization for the accelerometer is performed. The flow and mathematical model of the topology optimization for the accelerometer is built. A numerical example is presented to show the effectiveness of the method. The topology optimization results show that the output performance and sensitivity increase by 4.92%. The coupling of vibration modes is avoided and the quality factor is kept unchanged.

Abstract:The complex engine operation environment will result in interference while utilizing ion current detection technique to achieve real timing monitoring of the combustion consequentially. Anti interference design of the detection system was optimized. An experiment was done on a spark ignition homogeneous charge compression ignition (SI HCCI) engine. Results show that high voltage isolation module can protect collection system well; using capacitance to isolate ignition can reduce the interference from background; capacitance detection method cannot reflect accurately when knock phenomenon happens. Eliminating zero drift with a software achieves good effect. With the optimized ion current detection system, the ratio of signal to noise of ion current increases significantly in HCCI combustion.

Abstract:A 2 DOF nonlinear dynamic model of the automotive wiper system based on the theory of stick slip vibration was established. Bifurcation diagram and trajectories on the phase plane were adopted to confirm the pervasive phenomenon of stick slip vibration and to study its characteristics under various wiping velocities through numerical computation. Spatial and temporal distribution of stick slip vibration was analyzed by means of time histories and contour maps. Quantitative index of duty ratio of stick motion and quantity statistics of scraping were introduced to evaluate the wiping effect. The results indicate that the occurring of stick slip vibration and its characteristics under various wiping velocities possess complicated nonlinearity. The nonlinear stick slip vibration vanishes only when the nominal wiping velocity is higher than 0.725 m?s-1. Increasing the wiping velocity benefits the control of stick slip vibration and reduces the adverse influence on wiping effect caused by the heterogeneous distribution of scrapings.

Abstract:The influence on temperature field and thermal stress field of cooling stave with different kinds of special pipes(elliptical, rectangular, orthohexagonal, double circle and triple circle pipes) was analyzed by ANSYS. The results show that when the circular pipe’s perimeter is kept as a constant, the rise of maximum temperature and thermal stress on the hot surface of cooling stave is not high. In the case of keeping circular pipe’s sectional area as a constant, the maximum temperature and thermal stress on the hot surface of cooling stave decrease. This illustrates that when circular pipe is replaced by different sorts of special pipes, the heat transfer ability of the stave is improved. Consequently, the lifetimes of blast furnace are extended. Through use of elliptical pipe with the proportion of 0.6 between the longer axis and shorter as the optimum tubular, the flow of cooling water and thickness of the cooling stave can be reduced and therefore to reduce ironmaking costs.

Abstract:The research background of smoke flow property prediction system in fire building based on the network model was expounded. Then a major problem of concerned technology was found and solved. Based on the original network model of building fire smoke flow, the expressions related to opening installing ventilator were amended. The new expressions replaced the original negative mass expressions, and a solvable algebra equation set was obtained. Fire smoke flow property was calculated by the algebra equations set. Predicting software developed independently by Chongqing University for fire smoke flow property of high building was modified. As a result, smoke flow property in fire building using mechanical smoke extraction can be simulated.

Abstract:Cycle slip detection is always an important section of global positioning system(GPS) precise data processing. Some classic methods about cycle slip detection are adopted in practical data processing, but for single frequency un differenced phase observations, cycle slip detection and modification are hard to be realized. A new cycle slip detection method is proposed on the basis of the grey theory to predict the threshold limit by modeling tests which are constructed by pseudo range and carrier phase observations. This algorithm is analyzed with different sampling rate GPS static observations. The results indicate that the algorithm can detect and correct outliers properly for high sampling rate observations, which helps data quality controlling for un differenced precise positioning.

Abstract:The extraction and regulation of building boundary is a crucial step towards 3D building reconstruction, most methods that are appropriate for buildings of regular polygon cannot extract irregular building boundary which contains arc lines. A structure method for extracting building feature points is put forward by considering the irregular building boundary. By judging the property of feature points, feature points located at rectangular corner are adjusted with the parallel requirements to obtain accurate feature points, boundary points between adjacent arc feature points are fitted to an arc so as to get the real smooth boundary. Building boundary that contains arc lines can be efficiently extracted by proposed method. As a case study, LiDAR point clouds of Lujiazui in Shanghai are used to prove the feasibility and extraction accuracy of the method.

Abstract:On the basis of the analysis of tectonic and sedimentary background of Gaoyou Depression during the sedimentation of Dainan Formation, the sediments provenance of Gaoyou Depression during the sedimentation of the first member of Dainan Formation of Paleogene was analyzed by means of the heavy mineral assemblage analysis, mineral component analysis, sandstone ratio contour analysis, seismic reflection analysis and paleogeography analysis. It is considered that the north provenance of Gaoyou Depression during the sedimentation of first member of Dainan Formation is from Tuoduo lower uplift, and 4 provenances are developed, and the south provenance is from Tongyang uplift and Wubao lower uplift, and 5 provenances are developed. The map of sedimentary system distribution of the first member of Dainan Formation is presented.

Abstract:Through LA ICP MS dating, Zircon U Pb ages of 853 811 Ma were obtained for granitoids from Jiuling Terran of Jiangnan uplift. Since Jinningian, Jiuling terran had experieced Caledonian, Indo Chinese and Yanshanian movement. Different tectonic evolutions were obtained for the granitoids from Jiuling terran though analyses. The granitoids was formed in island arc and collision tectonic settings in Jinningian (929 810 Ma). The block convergence was the main character during Caledonian period (439 411 Ma). Granitoids formed in the volcanic arc and collision settings in Yanshanian Period (158 118 Ma).

Abstract:Cargo loss and damage in the logistics operation were introduced under the assumption of random demand and supply chain information being fully shared. An independent decision model and a centralized decision model were established with a supply chain of the supplier, the third party logistics service provider and the distributor. A revenue sharing contract was designed. Simulation and analysis results show the third party logistics service provider undertaking all the cargo loss and damage will result in the providers’ insufficient incentives. The Pareto optimization can be realized by selecting proper benefit allotting coefficients, and the third party logistics service provider is therefore encouraged to make efforts to reduce cargo loss and damage. Finally, the paper presents a proposal about the optimal order quantity, prices of the third party logistics service provider and supplier, range of benefit allotting coefficients.

Abstract:Considering the fairness, efficiency, constructing cost and some other factors of emergency rescue facility location, a multi objective decision model which can apply to different deployment decisions for large scale emergency incident facility locations. According to the general model of plant growth simulation algorithm, a solution method of target function based on plant growth simulation is proposed. By calculating on the real instances, the result shows the feasibility and rationality of multi objective decision model, the model is optimized with the proposed solution algorithm, the proposed method has a better performance.

Abstract:Assuming that the build operate transfer(BOT) projects be constructed by stages but transferred in the same time, a new decision making approach and model on concession term is presented based on real option. In order to preserve the profit of the government and construction quality of project, the approach to scientifically choose the concession term for BOT projects is analyzed in details. Finally, numerical experiment for practical engineer project further illustrates the proposed model is feasible and efficient.