Abstract:This paper focuses on the seismic failure mechanism of elevated pile-cap foundation in bridges. Pseudo-static testing were carried out on two 2×3 elevated reinforced concrete pile-cap foundation specimens in sand. Numerical pushover analysis based on Beam on Nonlinear Winkler Foundation (BNWF) model was conducted. Results indicate that side piles yielded earlier than middle piles. Each pile forms two plastic hinges at pile-top sections and under-ground pile sections with the depth of approximately 3~8 times of section width respectively, specimens suffer failure damage when the top section of the side pile attain to the theoretical ultimate curvature. The pile-top damage area is not sensitive to the above-ground height while the under-ground pile damage area is sensitive to the above-ground height.

Abstract:Modal pushover analysis method in transverse direction of multi span continuous bridges is studied for seismic performance evaluation of bridges in preliminary design stage. Moreover, effects of near optimal piecewise linear fits and FEMA356 fits in modal pushover analyses are compared. Modal pushover analyses with the two fits and nonlinear time history analysis of 3 continuous units of a constructing bridge are conducted. The conclusions are drawn that the modal pushover analysis method reasonably predicts the seismic performance of multi span continuous bridges; no obvious advantages of near optimal piecewise linear fits are shown in comparison with FEMA356 fits.

Abstract:Influence of underlying crushed rock on compacting effects and bearing capacity of jacked pipe pile was analyzed by general finite element method ABAQUS. Change rules of ground upwarping, ground horizontal displacement, compressive stress of pipe pile and foundation around it were discussed under the condition of different penetration depth of pile. Results show that installation of jacked pipe pile will result in ground upwarping around piles, and as the distance to the pile side is increasing, ground upwarping effect is weakening quickly. Installation of jacked pile will cause remarkable horizontal soil compacting effect around it. When jacked pipe pile is penetrated into underlying crushed rock, deformation effect of it around pipe pile is obviously weaker than that of soft foundation because stiffness of crushed rock is larger than that of soft foundation. The bearing capacity of pipe pile can be significantly increased, when the crushed rock layer is as bearing layer.

Abstract:To support integrated project delivery(IPD) projects, this research aims at developing a collaborative work platform. Based on a literature review of IPD cases, specific characteristics of IPD projects are summarized and a collaborative work model is established to reflect the implementation process of IPD projects. With the model, the information utilization mechanism for IPD projects is analyzed and a building information modeling(BIM) based framework for information utilization serving IPD projects is established, which lays a sound foundation for the development of BIM based collaborative work platform supporting IPD projects.

Abstract:Based on four forms of shared path route, a multi objective non linear mixed integer programming (MIP) optimization model of calculating the number of transit unit(TU) with separate or shared using mode is presented. A calculation software tool based on this model is developed and a case is proposed to testify the availability and validity of the model. The results show that the number of TU affected by five key factors such as headway of shared path sections, number of trains in different routes, running time of routes, layover time in terminals and the using mode (separate or shared) of TU. The practical application of the model to urban rail transit train plan maker (TPM) and its prospects are introduced finally.

Abstract:A cooperative control model was established based on mathematical programming to minimize the passenger loss delays and maximize their turnover by adopting the flow control rate as the quantitative basis. Then, an empirical analysis was made of Beijing subway Line 5 on the indicators of transport capacity utilization, retention rate and stranded passengers. Results show that this model can effectively improve the transportation capacity utilization, therefore, stranded passengers are reduced, and the contradiction between the passenger flow and the transport capacity is relieved.

Abstract:This study developed a simulation based approach to comprehensively evaluate the joint effects of penetration rate and uploading frequency of floating car data on traffic state estimation accuracy for the large scale complex road networks. A case study based on the simulation model of Lujiazui Region in Shanghai was conducted to demonstrate the applicability of the developed approach and explore the optimal penetration rate and uploading frequency in terms of travel speed estimation accuracy and network coverage. Totally, 30 combinations of the two parameters were tested in the calibrated simulation model. Results show that the accuracy of travel speed estimation and network coverage rise as the penetration rate and uploading frequency increase. The optimal penetration rate and uploading frequency are found to be 8% and 1/10 s-1 respectively.

Abstract:The risk factors were discriminated according to its influence on seismic risk of highway based on the principal component analysis and expert surveys. Four factors such as the peak acceleration, vegetation coverage, formation lithology, slope, were selected as evaluation factors for their significant effect. Traditional analytic hierarchy process was improved by resorting to the cloud model, and a weight approach was proposed for seismic risk assessment based on cloud model analytic hierarchy process. The scale scores of each risk factor was studied by using geographic information systems technology platform. The assessment model of seismic risk was set up, and the method was validated. The results indicate that the seismic risk index of the experiment area is 1.00~6.96. Seismic risk value of most regional is less than 5.00, the maximum value in the south and the southeast of the starting point with high peak acceleration, hard rock and large slop is close to 7. Risk assessment results agree well with the measured data.

Abstract:An osmotic microbial fuel cell (OsMFC) was used for simultaneous thickening and digestion of waste activated sludge (WAS) and converting chemical energy of WAS to clean electricity. The results show that with the load of external resistance of 470 Ω, the stable voltage output and power density reach 200~212 mV and 217~244 mW·m-3, respectively. Due to the use of forward osmosis(FO) membrane, the volume of initial WAS is decreased by 41.3% at the end of operation, and 58.7% of the water in WAS is recovered in the draw solution. During 24 d operation of OsMFC, the total destruction efficiencies of total chemical oxygen demand, mixed liquor suspended solids and mixed liquor volatile suspended solids are approximately 22.2%, 32.8% and 47.6%, respectively. OsMFC brings new visions for energy recovery and resource reclamation from WAS.

Abstract:Scanning electron microscope, infrared spectrum analyzer and Zeta potentiometer are used to explore the mechanism about the adsorption and the parameters effecton the adsorption rate of Pb2+ and Zn2+ by coffee grouds. Test results show that the maximum adsorption quantity appears when pH value is 4 and also 20 g·L-1 adsorbent is added into the aqueous solution. The maximum adsorption quantity of Pb2+ and Zn2+ by coffee grouds is 5.49 and 12.38 mg·g-1. The adsorption process reaches equilibrium after 4 hours. And the adsorption process accords with the second order kinetics model and Freundlich equation. The electronegativity of coffee grouds increase while pH value raises and it reduces after adsorpting Pb2+ and Zn2+. White particles appear on the surface of coffee grouds after the adsorption process. FT IR spectrum indicates that the main functional groups includes amide, ester and keto in the adsorption process.

Abstract:Based on Hummers’ method, the changes of groups and structure on oxidation process were discussed by modifying the oxidation time at the medium temperature. The results show that the content of oxygen containing groups increases gradually, especially the C—O bond, followed by CO and O—C=O bond; C—O bond emerges at the beginning of the oxidation, and the CO bond emerges mainly in the late stage of oxidation. The oxidation reaction occurs from the edge to the middle, corresponding to the color of graphite oxide's gradual changes from black to yellow. Throughout the oxidation process, with the increasing of distance between graphite layers, the structure of in place lattice is destroyed and the disorder increases gradually. The early oxidation damage to the in place lattice structure is more serious.

Abstract:Graphene (RGO) was prepared successfully through chemical oxidation pyrolysis reduction method. The chemical structure and morphology of the graphene were characterized by means of FTIR, XRD, SEM, TEM and AFM, respectively. It was found that the obtained RGO was a two dimensional material with monolayer or multilayer structure and a few numbers of oxygen containing functional groups on the surface. As conductive nano fillers, the as prepared RGO and commercial CNTs, fullerene, graphite were introduced into epoxy resin (ER) matrix to prepare the composite materials. The influence of the above carbon nano materials on the conductive property of ER was discussed. The results indicate that RGO is a superior conductive nano filler to others, which can improve the electric conductivity of ER greatly. The RGO/ER composite exhibits an electric percolation threshold as RGO volume ration is 0.25%; and the volume conductivity of RGO/ER composite can reach to 2.02×10-7S·m-1 when the RGO volume ratio is 0.50%.

Abstract:Mathematical model of mortar dynamic dewatering process was established based on theory of capillary mechanics and fluid mechanics, and it was verified through dynamic dewatering experiments. The relationship between model and water retention was further studied. Influence factors on water retention were discussed based on the model. The results indicate that the early stage and the later stage of mortar dewatering can be simulated by Capillary Gradual Contraction Model (CGC) and Capillary Integral Contraction Model (CIC) respectively. An inverse linear relationship was found in CGC instead of CIC between the rate of square of dewatering quantity and dewatering time and water retention rate. In addition, the influencing rule on water retention of fresh mortar of water, binder and cement sand ratio was obtained in theory according to CGC.

Abstract:This work studied the DSA behavior during high temperature LCF testing of 321 stainless steel. Through analyzing the hysteresis loops and peak stress curves at different temperatures, the results showed that most of serrated yielding behavior appeared at the first 10 cycles of LCF and then weakened. In addition, strain amplitude also had an effect on serrated yielding amplitude. The lower the strain amplitude was, the lower the serrated yielding amplitude became, and the faster the serrated yielding behavior vanished.

Abstract:A kind of thermotropic intelligent solar shading material was prepared. The effect of different ratio of raw materials, temperature and time on the change of transmittance, and the water quality and anti mildew agent on its resistance to mildew was studied. Results show that by adjusting the ratio of raw materials can make its transmittance changes between 80% ~ 90%. Temperature is the main factor of the change of transmittance of intelligent solar shading material. Introduction of anti mildew agent and adjust pH value can protect intelligent solar shading material from mildewing in 3 ~ 5 years.

Abstract:Based on the aerodynamic loads calculated by fluid dynamics and the high speed dynamic model, the influence of braking panels on vehicle vibrations and running safety were studied on the condition that two trains crossed each other both at the speed of 400 km·h-1, which meant the relative velocity was 800 km·h-1. The results show that the displacement and vibration acceleration of car bodies increase a lot when the two trains cross each other. In comparison with the model without opening braking panels, the safety coefficients, such as derailment coefficients, wheel load reduction rates, are different. However, all the results satisfy the safety standards.

Abstract:Combustion characteristics and kinetic parameters of four regional coal samples in O2/CO2 atmosphere were investigated by thermogravimetry(TG). The experiments were performed on low O2 volume fraction varying from 7.5% to 20% at a heating rate of 20 ℃·min-1. With Arrhenius and Coats Redfern equations, the kinetic parameters under different O2 volume fractions were calculated with the method of least squares linear regression. The results show that ignition temperature keeps constant and burn out temperature rises in lower O2 volume fraction. Activated energy, pre exponential factor and reaction degree all decrease in varying extent with the lower O2 volume fraction. There was compensation effect between activation energy and pre exponential factor, besides, the isokinetic temperature and reaction rate constant of four coal samples were obtained. When O2 volume fraction is lower than 12.5%, with reduction of O2 volume fraction, the reaction rate constant rises more and more mildly with the increasing of the temperature.

Abstract:The original discrete time Lipschitz nonlinear system with measurement noise and unknown input is transformed into an augmented descriptor system without measurement noise by taking measurement noise vector as an extended state vector. An H∞ unknown input observer which can estimate the state and the measurement noise of original system is developed, and the existence of the observer depends on the solution of the feasible solutions of linear matrix inequality (LMI). Then, an algebraic unknown input reconstruction method is proposed based on the delay estimation approach. The result of a simulation example is given to illustrate the effectiveness and correctness of the proposed method.

Abstract:We propose a method of converting AutoCAD standard format (DWG) map with extended attribute data to improved rules scalable vector graphics (SVG) format map. Both graphical data and attribute data are put together and regarded as a single object in SVG by defining improved SVG rules, which assures the data integrity of the conversion. Meanwhile, flat hierarchical management in DWG is improved in SVG by defining SVG hierarchical rule. Experiments validate that the conversion method is effective.

Abstract:This paper puts forward a method to use metal slice to filter high energy X ray. In order to eliminate the overlap as well as the unbalanced total energy between two energy spectrums as much as possible, this paper develops a dual energy inspection system model based on the Monte Carlo Method and creates a cost function to choose the optimum metal material and thickness. A practical X ray inspection machine is used to test this method. The result indicates that this metal filter method and concerned filter parameters obviously contribute to the performance improvement of dual energy inspection system, which attests to the effectiveness of this method.

Abstract:This paper develops a multi layer stimulation and collaboration model based on the multi phase game theory, where a client, contractors and subcontractors in a typical construction project form a multi echelon and multi party management system, and profits are shared among those participants by distribution functions. The assumptions are that all contractors in this model are risk neutral and they are willing to pay efforts in order to earn more profits, and the constraint conditions are the profits of general contractors and sub contractors, who will become cooperative partnership. It is revealed that contractors’ collaborative effort is related to collaborative cost, but irrelated to her fixed cost, and the profit distribution function depends not only on her collaborative efficiency but also on reciprocal collaborative efforts, which contributes to the improvement of the project management overall performance by avoiding the opportunistic participants.

Abstract:As for the supply demand relationship between online store and the third party logistics(TPL), the concept of the distribution perfectness ratio was introduced to reflect the service quality of TPL. A non cooperative game model and a cooperative game model were constructed respectively upon the assumption that the market demand function depended on the product price and perfectness ratio of distribution. A comparative study of the two decision models revealed the deficiency of traditional contract and the feasibility of the redesigned contract in supply chain coordination. Computation example analysis results show that the logistics service quality contributes to the total revenue of the supply chain. Pareto optimality can be realized by selecting proper benefit allocation coefficients, whose range are recommended correspondingly. Additionally, coordination contract proves to be effective in reducing TPL’s service prices and the online stores’ product prices.

Abstract:This paper analyzes how an individual logistic service integrator distributes its orders to the functional service suppliers in service supply chain. We introduce a dynamic integer programming model with multiple tasks and targets, in multiple periods. An example is given to prove the feasibility of the model. We also propose an updating model to schedule order distributions in multi periods, with the introduction of the mechanism of executing part of the solution then adjusting according to the updating information. We conduct a simulation. Based on a comparison between the linear weights MOP model and the service constrain model, the simulation result demonstrates that our model generates a lower cost while ensuring the satisfaction of service requirement.

Abstract:A coordinated replenishment policy is discussed for a two echelon dual channel supply chain model with multi products in dynamic demand conversion periods. The application of TOC SCRS in manufacturer determines the replenish frequency in manufacturer warehouse. The retail store employs a modified integer ratio policy to synchronize the replenishment between each node and each product, and increase inventory turnover rate. The objective of this model is to minimize the sum of replenishment cost, inventory cost and the shortage cost, subject to the customer satisfaction and storage capability constraints. Finally, a numerical experiment based on modified GA is presented to compare three strategies with sensitivity analysis. Numerical experiment results show that compared with (s, S) strategy, 15.36% and 9.74% gaps are gained by MIRP and Integer ratio policy.