Abstract:The obvious deformation of the box girder being due to some cross-section distortion effect,affects seriously the normal use of the bridge. Based on the Hamiltonian dual calculating system and the precise integration method,the Hamilton canonical equation about free vibration analysis of thin-walled box girder considering distortion was established by suing the basic assumption of the generalized coordinate method,and the corresponding programs were compiled by MATLAB. The dichotomy was used to calculate natural frequencies of structures. Finally,the comparative analysis of specific examples proved the correctness and feasibility of this approach.

Abstract:Using the generalized Gaussian distribution,this paper proposes an effective method to the analysis of the marginal and joint distributions of random responses of nonlinear structures subjected to random excitations. The marginal probability density function(PDF) of a nonlinear random response is modeled by the generalized Gaussian distribution and the joint PDF of the responses of interest is obtained by the Nataf model. The model parameters required by the method can be estimated by simple estimators. Numerical examples,a six-story shear-building structure under random earthquake loading,show that the method is very effective in the sense that it provides sufficiently exact solutions for the hardening as well as softening random responses with feasible computational efforts.

Abstract:This paper aims to investigate the ductility behavior of partially concrete-filled steel box-section bridge piers by 2-D beam element formulation. Twenty beam element models are established,in which three parameters,the flange plate width-thickness ratio,slenderness ratio of steel piers and height of filled-in concrete are considered. The correction coefficient of ductility behavior obtained from 2-D beam element formulation is proposed by comparing the numerical results with 3-D accurate results. The modified 2-D simulation results are in line with the experimental results,which indicate that the proposed numerical method and the correction coefficient are accurate and valid enough. The increase of concrete filling rate can effectively improve the ductility of steel bridge piers. Increasing of the flange plate width-thickness ratio and slenderness ratio of steel piers will lead to a decline in steel pier ductility.

Abstract:The influence of limestone powder with different mixed law(0%,5%,10%,15%,20%) on the workability and strength of concrete were studied. The results show concrete slump with limestone powder is smaller than the baseline group,but its cohesiveness and water retention are in good quality. The compressive strength of concrete shows a trend of first increase and then decrease with increasing of mixing amount of limestone powder,the concrete compressive strength is highest in each age(7 d、14 d、28 d) when limestone powder dosage is 10% than other groups.

Abstract:The deformation monitoring and analysis in the process of dismantling inner support is crucial. In this paper,a super deep foundation pit engineering was taken as the research background,the rule of a deep horizontal displacement of the supporting structure,ground settlement,vertical settlement and axial force of support in the demolition process of support were monitored and analyzed. It was obtained that the settlement of surface ground around the foundation shows spatial and temporal clearly and the distribution of deep horizontal displacement of supporting structure is similar to the parabolic whose the maximum point constant upward shift with supporting continuous removed. Soil pressure of supporting shared with support removing process changed obviously,and the earth pressures of lateral support sharing show increasing trend. From the monitoring results,the demolition scheme is reasonable and effective and meets with the requirements of design and environment.

Abstract:Based on analysis of the basic soil mechanics properties of natural argillaceous siltstone which are located in different sections of the construction site,the method of adding lime or cement to improve the soil is raised. Furthermore,we can define the difference of lime and cement mixed in soil through unconfined compressive strength and CBR test,which will help to determine the way to improve the subgrade by mixed with cement. Finally,we observe the changes in the strength of cement soil under the dry-wet cycle test,which simulate the process of cement soil under the environment of frequently alternate dry-wet on site. And the reliability of improving argillaceous siltstone by cement is confirmed ultimately.

Abstract:The pile-soil stress ratio and the lateral displacement of plastic tube cast-in-place concrete pile with supporting disc(TC pile with disc) in the engineering of bridgehead segment was investigated by relying on road engineering in Shanghai and laying the relevant test equipment in the engineering of bridgehead segment. Based on persisted data monitoring,the TC pile with disc's pile-soil stress ratio distribution was obtained from the measured data with scientific analysis. It was found that it is hard to form soil arching under the lower embankment; and the soil under roadbed has a long soil return extrusion because of the construction process. Then the paper pointed out that after the TC pile with disc completed should apply enough load and continued enough time,make the soil around the pile to fully return extrusion,so that the TC pile with disc can full play its strength,reducing the bridge section settlement.

Abstract:According to the monitoring data mediator Nanjing Metro Line station,this paper analyzed the deformation characteristics of the underground continuous wall. It is found that the law of space effect is quite obvious during excavation retaining structure deformation; and the amount of land in the vicinity of the lateral wall of the base reaches a maximum with the increasing of excavation depth. It is also found that a wall changes similar parabola,the lateral displacement of the wall decreases with increasing of their stiffness and. Combined with plane finite element analysis software plaxis and HS wall deformation constitutive model,the main factors were analyzed. The analysis results suggest that,the thickness of its walls takes(2. 5% ~ 3. 5%) H when the Nanjing area of excavation depth is H.

Abstract:The method of double-sides-wall drift is usually adopted when shallow buried large section tunnel is excavated,and the core rock is a quite important factor to the displacement stability of the surrounding rock mass and the internal force of supporting during excavation. Based on a subway tunnel(Beibei station) in Chongqing,FLAC3 d is used to simulate shallow buried large section tunnel with method for the of double-sides-wall drift and construction method for the core rock. The change of surrounding is compared and analyzed before and after reserving core rock. It was found that a reasonable design of core rock can reduce the stratigraphic sedimentation rate and improve the stress distribution of surrounding rock. Meanwhile,the arch protection method and the temporary backfill slurry method have a good effect on the reinforcement of landslide.

Abstract:Through interior shear rheological tests,this paper study the anchor creep effect-the mechanical properties of bolt-grouting body interface and anchor pre-stressing loss changes over time. The results show that anchor pre-stressing loss increases along with the increase of the load increases under conditions of considering creep effect; bolt-grouting distribution of interfacial shear rapidly increases with the length of the rod to the peak,then gradually reduced small,and with the growth of time,the peak gradually shifted and then disappear finally.

Abstract:The sand-gravel pile and the plain concrete pile of combined composite foundation adapted to ground treatment of large circular coal storage bunker on soft dredger soil,the results of field test pile meet with the design requirements. After the foundation treatment,the quality of the sand-gravel pile was good,the liquefaction between pile and soil was eliminated,the bearing capacity of foundation was increased significantly,and the economic benefit was obvious.

Abstract:This thesis talks about the harassing people from square dancing,in order to reduce the negative effects,the first research step is a survey of squares allocation,includes the kinds and the features of the urban recreational squares,the facilities,activity crowds' composition and main exercises contents in squares,then this paper analyzes the negative effect from the crowd activity in squares,such as noise nuisance,poor sanitation,facilities easily damaged. At the end,the article proposes some countermeasures to reduce the external interference.

Abstract:The landscapes of lighting field in Egret park during the day and evening attractions were researched and the environmental illumination during the day and evening are measured by using the luxmeter; the flow of people to visit scenic spots,tourists Egret park night landscape lighting comfort feeling are recorded by times. Then,this paper carries on the analysis from the data analysis and subjective analysis of two aspects of design in Egret park landscape lighting comfort through combining control standards,the scenic landscape lighting problems are discussed,and the suggestions are given. The authors hope to provide some reference and inspiration for the landscape lighting designers.

Abstract:Based on the analysis of the factors involved in the demand of parking place,the parameters were introduced to improve the parking generation rate model,including the land development intensity,the growth rate of trip proportion by car,the turnover rate and utilization ratio of the berth during the rush hour. Accordingly,the demand of parking place in CBD of Handan was evaluated and the demand in 2020 was also forecasted. The results show that the current supply of parking place sustains a serious shortage and still need lots of land resources to build parking facilities,which exert huge pressure on the traffic in CBD of Handan. Therefore the multiple control strategies should be used from supply and demand to reduce the negative effects of the redundant demand of parking places.

Abstract:The current research and practice about livable city focused on the scope of urban built-up area is contrary to the initial livable ideas which is focus on urban and rural dual space and social integration,so this article introduce the concept of urban-rural integration to the livable city study.Then through the study on the core idea of urban and rural integration and the nature of the livable city is carried to know the internal mechanism about the livable city around the super-large city,also to learn from successful livable cities in our country in order to build the path contents for the construction of the livable city near the super-large city,including spatial function,eco-environment,facilities and services,and cultural development. Ma'anshan City is taken as the example for empirical research.

Abstract:Based on the indoor flume experiment and theoretical analysis,a two-layer model(i. e.the vegetated layer and the upper non-vegetated layer) is proposed to predict the vertical distribution of longitudinal velocity in the flow with submerged vegetation. For the upper non-vegetated layer,a modified mixing length theory combined with the concept of the new vegetation boundary layer was adopted,and an analytical model was presented to predict the vertical velocity distribution in this region. For the vegetated layer,the analytical solution was presented by fitting the experimental data.Finally,by analyzing the experimental results,the two-layer model is in good agreement with the results.

Abstract:Considering water resources exploitation at present in Sanya city,the water resources allocation model based on regulating rules in Sanya city is established. According to hydrological data from 1956 to 2010 and relevant data in the planning year,water resources allocation in Sanya city in2020 is realized. The results have an important significance to promote coordinated development between water resources and social economy.

Abstract:Based on the engineering background of new inclined roadway through mined-out area in the Pingdingshan Sixth Mine,the numerical analysis and field monitoring are used to study the overburden rock fracture characteristics and its mine pressure in mined-out area. Aiming at the characteristics of broken surrounding rock in mined-out area when the inclined roadway passed through this area,the supporting plan of metal net + whole section U-shape steel + bottom-arch linkage girder+ concreting + backfill grouting is put forward. The internal and external bearing structure formed by"Double-shell support"can largely improve the integrity of broken rock mass in mined-out area.Field monitoring shows that in the mined-out area passed through by inclined roadway convergence of ribs is 26 mm,and convergence between roof and floor is 47 mm,and the goal of effectively controlling roadway surrounding rock deformation is achieved.

Abstract:We made the near-surface luminance temperature through the sixth band of Landsat TM /ETM + sensors from 1988 to 2010. We analyze the space structure characteristic and the change of area percent,the result showed that the position of high heat island was stable,but the large low and sub-low area change to the middle,sub-high and high temperature areas. The heat island extended from north-east to south-west,and the areas of heat island was enlarge in 20 years. The reason for these may be the change of the city's underlaying surface resulting from the urbanization,so how to improve the composition of the underlaying surface,is desiderate for relieving the Handan's heat island effect.

Abstract:There is a huge discrepancy between the calculated permeability coefficient and the actual situation of the aquifer being due to some factors such as the complexity of the hydrogeology and the diversity and relative difficulty of counting accurately. With specific illustration,this paper will take the experiment with the steady flow pumping test of the fully penetrating well in the coal-bearing strata aquifer in XJ-7,an exploration area,as an example. In this experiment,we took different methods of analyzing the statistics of groundwater level decrease and water-level recovery respectively. Through the comparison between these two methods,we find out that the result of the latter counting method that K = 0. 058 9 m·d^-1is much accurate and reasonable. This experiment thus demonstrates the permeability coefficient is of low accuracy when applying the Dupuit Formula into the practice of single-hole steady flow pumping test. By contrast,the counting result in the water-level recovery period is much more reliable because of the smaller and insignificant influence of both human and mechanical factors.

Abstract:The forty original data of shear wave velocity in Handan area that had been collected were analyzed by using the quantile regression,the quantile regression models of two kinds of soil had been obtained by analyzing the changing law of shear wave velocity with depth increasing. The regression parameters and regression curve equation were obtained. The results show that the effect of depth to silt's shear wave velocity is unipolarity,and the effect of depth to silt's shear wave velocity show a trend of first increase and then decrease.

Abstract:14 samples of No. 4 coal seam are taken from the Chuancaogedan Coal Mine,Jungar coalfield,Inner Mongolia. Combined with coal plant type and sedimentology characteristics,the petrographic properties and coal facies type of the coal were analyzed by use of coal microscopic method.The results indicate that the maceral of the No. 4 coal seam is enrichment in vitrinite. In the whole evolution process of the swamp,the No. 4 coal was deposited dominantly in moist forest peat marsh,as well asin open moor and shallow water forest swamp facies occasionally. The evolution of the swamp can be divided into two stages. The extent of the overlying water in the No. 4 coal seam from bottom to top shows a strong-weak-strong change. There are two types of swamp hydrodynamic conditions in the No. 4 coal,the retention swamps and running water swamps periodic appear alternately.

Abstract:The problem of the gas emission of the working face was characterized by small samples,nonlinear,and it was affected by complex factors. Using the genetic-least squares support vector regression algorithm to predict the gas emission could avoid the qualitative analysis limitations and effectively improve the accuracy of the forecast,because it was a quantitative method for analysis. First,the model used the genetic algorithms to train and optimize the least squares support vector regression parameters,and then used the genetic-least squares support vector regression model to predict the amount of gas emission of test samples. The test results show that: the genetic algorithm-least squares support vector regression model has a higher reliability and accuracy,compared to the predicted values of the support vector regression and the least squares support vector regression.

Abstract:Power measurement is an important part of solar photovoltaic power generation system. This paper presents a photovoltaic power generating capacity detection system that consumes less energy,lower cost and gives a more precise value. The system uses AVR single chip computer as the controller,avoiding consumption of analog-digital conversion and others,and simplifying system structure.At the same time,Hall current sensor is used to change current signals into voltage signals with least energy consumption. The experimental results show that photovoltaic power generating capacity can be displayed on the screen in real time,and the error rate will not exceed 5% when working.

Abstract:The method of CAD-CFD analysis was used to study the design method of the theory and practice spiral case and its internal flow,the relation between the axial symmetry and uniform flow,hydraulic loss,formation of circulation and overall dimensions of spiral case were discussed,and the measures to improve its working performance were summed. The results indicate that the axial symmetry and uniform flow can be optimized by enlarging the sectional area of the nose section and the circulation can be changed by adjusting the inlet area on the basis of the traditional spiral case designed by"circulation".

Abstract:On account of the high-speed motorized spindle system,the heat generated will inevitably produce a fever and lead to the spindle thermal deformation. In this paper,the thermal characteristics of high speed spindle unit were analyzed based on the ANSYS. This text uses the finite element method for modeling to calculate the heat generated and the thermal convection on each part of the spindle;through the analysis of ANSYS,the temperature distribution of high-speed electric spindle unit,axial and radial displacement at the end of main spindle and corresponding displacement diagrams are obtained. The thermal state performance can be analyzed thermal induction pre load,and calculated the homologous intensity and the critical speed. The study also found that the effect of heat induced pre load should be considered in order to obtain more pre load.

Abstract:Based on the temperature of hangang wide-thick slab continuous casting mold copper plate measured by thermocouple,the finite element heat transfer model and non-linear model were built to estimate the heat flux. Taking the results of back calculation model for getting heat flux of copper plate,and contrasting with the average heat flux calculated by heat balance,we demonstrated the validity of modelto confirme the heat flow formula of copper plate wide and narrow surface. The temperature distribution of copper plate was analyzed at the same time. The temperature curve of copper plate hot and cold sides are of a wavy distribution,the temperature of hot side changes more gently,cold side has the largest temperature difference as 29. 4 ℃. The temperature of copper plate decreases with the increase of the distance to the meniscus,but the temperature back to rise at 23 ℃.