Abstract:In order to study the vulnerability of the frame structure based on the inelastic displacement response spectrum, six different periods of reinforced concrete frame model are established by finite element software. Then propose four limit states quantization index of evaluating frame structure damage. The fragility curves of frame structure were obtained by IDA analysis method; Seismic hazard curves were obtained by using the response spectrum method, and then get the frame structure seismic collapse safety reserve coefficient. The results provide a reference for the future evaluation of the vulnerability of the framework structure.

Abstract:In this paper, an adaptive genetic algorithm (AGA) which can adaptively select crossover probability and mutation probability is presented to optimize the fuzzy control system for the space intelligent truss structure. Firstly, considering the electromechanical coupling characteristic of piezoelectric active bars, the finite element dynamic equations of the system are established. Secondly, the optimization goal is the minimum of axial displacement difference of intelligent truss active bars. An adaptive genetic algorithm is applied to optimize fuzzy control rules to improve the control effect of fuzzy controller of intelligent truss structure. To demonstrate the effectiveness of this method, the model of space intelligent truss structure is established by the Matlab/Simulink simulation, and the control results of fuzzy rules before and after optimization are compared. Simulation results show that after the optimization with adaptive genetic algorithm, the intelligent truss vibration damping rate has also been accelerated, and the steady-state error of fuzzy control are effectively eliminated.

Abstract:Dynamic parametric inversion plays an essential role in evaluating the health ststus of pump room structure, Huai'an third station was taken as the engineering background for pump structure dynamic parameter inversion. According to the measured first order frequency and the measured acceleration peak value, parameter inversion of pump room structure was carried out on bases on improved genetic algorithm. The more reasonable calculation model was obtained by comparing the effects of the material parameters of pump structure inversion between simplified model and spring constraint model. Reasonable calculation model was more in line with the actual situation of the project and could improve the accuracy of finite element analysis, so as to establish a good foundation for the inversion analysis. The results show that the spring constraint model is more realistic and the result is more accurate than the simple model.

Abstract:In order to propose application of durability design technology in the design of recycled concrete structures to extend the applied field of durability design, the durability design of recycled concrete structure exposed to corrosion environment was analyzed based on the durability design of concrete structure, and the important achievements obtained on the study and application of recycled concrete structure in China. A basic design method for durable recycled concrete structure is presented in this paper. The environmental factor and the quality control requirement to guarantee the durability of recycled concrete structure are taken into consideration in the method. The results show that when the recycled coarse aggregate replacement ratio is 30%~50% and the recycled coarse aggregate replacement ratio is more than 50%, the protection cover of reinforcing bar should increase respectively 3 mm and 5 mm,and the curing time of recycled concrete should increase respectively 24 hour and 48 hour.

Abstract:The classical weak expansive soil existed widely in Hefei was treated by mixing with randomly and uniformly distributed jute fiber. And a series of direct shear and unconfined compression tests were conducted on soil samples of ten groups including expansive soil and reinforced soil with jute fiber of varying fiber content and fiber length. Besides, the improving mechanism of fiber reinforcement and the effects of fiber length and fiber content on the strength characteristics of jute fiber-reinforced soil were analyzed briefly. Results of this investigation show that:Incorporating randomly distributed jute fiber into expansive soil could enhance observably the shear strength of soil, Jute fiber reinforcement improved the shear failure mode of expansive soil, at the same time, the length and the width of the fractures on the surface of soil specimens after failure reduced largely.

Abstract:To obtain the ultimate bearing capacity of suction caisson under inclined load in saturated sand, the interaction failure envelop was used to analyze the bearing behavior of suction caisson. Based on the 25 model tests in sand, the ultimate capacity of suction caisson under different loading conditions was summarized. The lateral capacity factor and the vertical capacity factor were assumed to analyze the influences of the loading position, loading inclination angle on the ultimate bearing capacity. It was found that there is a power function relationship between the normalized ultimate horizontal bearing capacity and the normalized ultimate vertical bearing capacity. Thus, the ultimate inclined bearing capacity can be obtained with the loading angle between the horizontal capacity and the vertical capacity.

Abstract:Aiming at deep horizontal displacement problem in the process of excavation construction of the second District Provincial Museum Station in 3 east section of Kunming Rail Transit Line, this paper sets up the displacement prediction curve on basis of MATLAB simulation and the establishment of BP neural network model through the input displacement data. The experimental data shows that the BP neural network model has good predictive power for the deep horizontal displacement. This method provides a new technical means for the displacement control of underground engineering.

Abstract:In order to improve the computing efficiency of the simulation for jacked piles andto improve the shape of the deformed mesh which has a significant influence on the calculation accuracy, ABAQUS/Explicit module and ALE adaptive meshing are used to achieve the quasi-static analysis of penetrating jacked piles. Meanwhile, a sensitivity analysis is performed onpile-soil friction, the elastic modulus and internal friction angle of the soil.

Abstract:The foundation treatment method which was mass stabilization in-situ was proposed in order to instead of the replacement method at the low filling embankment road,as to meet the bearing capacity of road design. The laboratory,theoretical calculation and field tests were applied to research on the mass stabilization and the bearing capacity.The composition and content of the curing agents were determined by the variation of unconfined compressive strength in the laboratory test. The analysis of using different ways of construction of ALLU mixing system in situ shows that the field strength and indoor strength ratio is between 0.37 to 0.66;The bearing capacity of mass stabilization was obtained from the load plate test, standard penetration test and static cone penetration tests using ALLU PMX (power mixing tool) in situ. And bearing capacity of mass stabilization in situ was compared with three different theoretical calculations. Design theory is put forward, providing the basis for the follow-up construction.

Abstract:In order to study the characteristics of electric sounding curve corresponding to different laying depth of the membrane in detection of impervious membrane in Vertical Laying plastic Film project, several groups of indoor experiment with different laying depth of membrane paving inside the saturated soil using DC resistivity method were taken. It was found that the electrical sounding curves of the measurement of the point on the surface of the sand above the membrane along the cross-section of the membrane character as follows:the apparent resistivity corresponding to the detection range of each electrical layer changes with constant gradient which has a close relationship with the laying position of the membrane.

Abstract:Taking a three-tower self-anchored suspension bridge as the research object, based on the data of Three-tower Self-anchored Suspension Bridges built at home and abroad, the Economic performance of the Three-tower Self-anchored Suspension Bridge is studied, the conception of materials consumption with structural parameters and mechanical property is established. And the effects of the material of girder, rise-span ratio, side to center span ratio for the total cost are studied. Come to the conclusion that changing the material of girder has much impact on the cost of three-tower self-anchored suspension bridge; Increasing the rise-span ratio can reduce the cost of main cable significantly; The side to center span ratio should be the largest value in the reasonable scope when the total length of a bridge has been defined.

Abstract:Based on the strength of existing material, the research studies the ultimate span of steel cable and CFRP cable suspension bridge using analytic method. The result shows that the diameter of steel cable will increase sharply and its self-weight will account for 95% of total loads when the span is over 4 500m, which is no more suitable to adopt; however, the area of CFRP cable can still grow steadily when the span is over 5 000 m and its value is far less than the one of steel cable in same span, which is rather feasible. In addition, steel cable and CFRP cable suspension bridge with main span of 1 500, 2 000, 3 000, 4 000, 5 000m are tried to be designed and comparative analysis of their mechanical properties are made in the study. In conclusion, it is suitable to use steel cable when the span is less than 2 000 m while CFRP cable is more feasible when it is over 3 000m.

Abstract:In this paper, the ripple web composite box girder bridge (50m+80m+50m) of Xingtai Xing Heng highway segment was regarded as an engineering example, the model of ripple web composite Box Girder Bridge was established by the finite element software Midas. The basic mechanical properties of box girder of different geometrical parameters on rigid web were analyzed, the results show that the deflection of box girder is very small due to the variation of geometric parameters of the web. Besides, it is favorable to reduce the length of straight line segment. The results also show that the torsional stiffness of the box girder can be increased obviously with the corrugated web relative to the flat web plate, and the greater the bend angle, the greater the torsional rigidity of box girder. Additionally, the increasing of the thickness of the web can improve the performance of box girder.

Abstract:Considering the condition of Dazhongshan 1# shallow multi-arch tunnel unsymmetrical pressure in Shihong Expressway, and setting testing component in typical cross-sections, the tunnel's surrounding rock and supporting structure force are duly monitored. After the analysis of the monitoring date, according to site monitoring and information feedback, the surrounding rock deformation and supporting force were analyzed in-depth during the excavation of the tunnel and summarized the characteristics of force and deformation when the tunnel under unsymmetrical pressure. The results indicate that the tunnel has the inclination to the side of shallower depth of cover under the asymmetry, which makes an important role in guaranteeing the structure stability. Based on the engineering case, the article discussed the stability of tunnel during the excavation, which can provide reference for similar works.

Abstract:Marshall compaction test were carried out for crumb rubber asphalt mixture parameters, aspects, aggregate properties, compaction methods. The wax seal maximum dry density, porosity and aggregate ratio were analyzed, derived affect rubber asphalt variation factors and compactness. The results show that the powder content on the density of the mixture is very small; For mixture gradation using for Long-nen highway, improvement room for the density by optimizing is not graded; Aggregate water absorption effects obviously on the porosity. When water rate increases by 1%, the mix porosity increases by about 2%; the same Marshall specimen with 100 times compaction times reduces the porosity of 31% than 75 times compaction; the porosity changes only by 1.6% through changing the method of compaction.

Abstract:In order to improve the effect of heat and mass transfer, studying the influence laws of heat and mass transfer effect of various factors is of great significance to improve the efficiency of heat and mass transfer of spray chamber. This paper adopted the numerical simulation method, and carried out the contrast research of the water-drop law of motion and effect of air-water heat moisture transmission in vertical spray chamber which have two kinds including the upward-spray type and the downward-spray type. The result shows that not only the water residence time, but also the heat transfer effect the upward-spray type is superior to the downward-spray type.

Abstract:This paper chooses 0.1 μm~20 μm monodisperse particles as the research object. We adopted numerical simulation methods to study the transmission characteristics of particles in the straight horizontal sampling tube under laminar flow. Diameters of tube are 4 mm, 7 mm and 10 mm. The lengths of tube are 0.2 m, 0.5 m, 1.0 m and 1.5 m. We got the flow field of the tube and the particle concentration distribution. Through the analysis of simulation results, we obtained the transport efficiency of particles in the straight horizontal sampling tube. Based on the numerical simulation of particle transmission characteristics within the straight horizontal sampling tube, it is found that the particle loss is mainly from gravity and diffusion. Simultaneously, the particle transport efficiency is influenced by particle size, tube length and inner diameter. Under laminar flow, the transport efficiency of 0.1 μm~1.0 μm particles is almost 100%, without the influence of inner diameter, tube length, gravity and Brownian diffusion force. The transport efficiency of 2.5 μm~20 μm particles decreases with the increasing of particle size, tube length and inner diameter. Through the analysis, it will improve the transport efficiency of particles by reducing the length of the sampling tube or the inner diameter on the basis of a flow.The simulation results compared with the theoretical formula, it can be approximated that the transport efficiency of particles is equal to the product of particle transport efficicency respectively under the action of gravity and diffusion.

Abstract:To research the seawalls stability against sliding under high tide level in construction period, limit equilibrium and finite element shear strength reduction methods were used to analyze the stability with the physical and mechanical parameters from indoor tests. Under the effect of self-weight, rainfall, wave and earthquake, a certain seawall under high tide level is stable for both upstream and downstream slopes from simulation results. However, the rapid changes of tide levels may lead to decreasing the stability of seawalls, and the higher the tide level, the bigger impact on seawalls.The rainfall and earthquake may also decrease the stability of seawalls. The long-effect mechanism of the wave to seawall stability should also be focused in the study.

Abstract:Based on the slope of mining in Nanjing area as the background to studied the stability of the soft and hard rock slope. The FLAC^3D with the strength reduction FEM was used to solve the different hard rock strata dip and strata thickness to influence the bedding slope and reverse slope's deformation, then the influence of the above factors on the slope deformation were analyzed and compared. The results show that the dip angle of the hard rock in the slope is bigger, the thickness is bigger, the deformation is smaller and the deformation tends to be stable; the dip angle of the reverse slope is bigger, the thickness is bigger, the deformation decreases and then increases, which shows that the reverse slope is prone to dumping deformation.

Abstract:This paper discuss the numerical simulation of impeller rotational speed's impact to force flow trace experiment. Final tracer concentration duration curves indicate that the in the flow field of karst caves, the time inflection points appear on tracer concentration duration curve are brought forward as the hydrodynamic condition is promoted, and in 1D karst caves, tracer concentrate correspond to inflection points reduce along with the ascension of the hydrodynamic condition, in 2,3D karst caves, it may rise the phenomenon that tracer concentrate correspond to inflection points rise along with the ascension of the hydrodynamic. In 2,3D karst carves, when hydrodynamic intensity is small, the tracer's migration has little to do with the hydrodynamic conditions and increase steadily as the hydrodynamic conditions promote, when hydrodynamic intensity is large, tracer migration rate rise in nonlinear as the hydrodynamic conditions promote. Therefore, through the analysis of the force flow tracer curve's shape can roughly deduce the underground karst cave's spatial dimension.

Abstract:According to the determination of basic parameters of gas in coal bed, bedding in the laboratory on drilling under the condition of reducing gas concentration, flow and drainage radius parameter change rule has carried on the numerical simulation, and the way of the valve in Bai shan ping coal mine 1265 coal mining face verifies the effect of the drainage radius. It is found that the numerical simulation results are in good agreement with the measured results. The final result shows that the mining face in order to ensure the safety in production, the hole diameter should be better with 75-100 mm.

Abstract:In order to investigate heat transfer and resistance characteristics of H-type finned tube in the low pressure economizer, realizable turbulence model was adopted to analyze flow and heat transfer characteristics of flue gas covered by H-type finned tube. The results show that the H-type finned tube can make the airflow become uniform; the vortexes formed on the wall are favorable to enhance heat transfer because of detouring flow in the channel; the higher velocity of flue gas is, the larger heat transfer coefficient of H-type finned tube and flow resistance will be; with the increase of pitch of the finned tube, the heat transfer coefficient increases, flow resistance decreases; when the pitch of H-type finned tube is 18 mm, the value of heat transfer coefficient reaches a peak and flow resistance is smallest. Therefore, the selection of 18 mm-pitches H-type finned is most economical.

Abstract:Hydraulic torque converter optimization design was based on CAD-CFD, this paper analysis the influence factors to the whole performance and optimal design the hydraulic torque converter. Modeling of the hydraulic torque converter was parameterized by using BladeGen at first, the working conditions in different speed ratio were calculated by basing on CFX, statistical performance curves of the hydraulic torque was compared with experiment results. This paper analyzed the characteristics of energy head distribution, and obtained optimal structure by according to flow field, made aerofoil structure in internal and external ring adapt to the working conditions with different speed ratio, the energy head optimization of state working in low speed ration working conditions was achieved, which above increasd the turbine output torque; the maximum increment of turbine output torque at low speed rate working conditions reached to 175.36N·m. After optimization, the hydraulic torque converter torque ratio increased 0.344 with 0 speed ratio working condition,the efficiency increased 2.95% in 0.274 speed ratio working condition.

Abstract:An indoor the real-time positioning technology based on Extended Kalman Filtering (EKF) algorithm is proposed to solve the problem that the forecasted position error is larger. Systems based on fingerprint positioning WiFi signal, and the Kalman filter is used to filter the forecasted location in order to improve the accuracy of WiFi fingerprinting positioning method, to achieve real-time tracking of the target. The simulation and experimental results illustrate that method improves the positioning precision, can better fulfil requirements of indoor positioning.