Abstract:Considering the boundary and the surface conditions,the stress field and displacement field caused by the construction of the shallow rectangular pipe jacking are solved by the complex function method. According to the Riemann's existence theorem and basic complex variable theory,a conformal mapping function which can transform the half-plane with a rectangle cavity into the concentric ring is established. The both sides of boundary conditions equation are expanded into Laurent series,and then the coefficients of complex stress function are solved by power series method. The derived solution is applied to an example and a comparison is made using FEM method to show the accuracy of the methods,the results of this paper are almost the same as those of the FEM method,and the error is about 2%. The result shows:(1) The method presented in this paper is applicable to a shallow buried rectangular tunnel;(2) The complex function method proposed in this paper is characterized by clear steps,fast convergence and simple operation.

Abstract:The fracture energy of concrete for different cases is calculated by means of three-point bend tests,and large sample tests of one case are done. Based on the test data of this experiment and other articles,statistical model about fracture energy of two factors,concrete strength and maximum aggregate size,are established. Compared the statistical model with other models,the ability of prediction is better than other models,and it can prove rationality of test data indirectly. Statistical analysis system (SAS) is applied to compare four probability distribution and five goodness-of-fit tests,the most suitable probability distribution of test data is lognormal distribution. Based to lognormal distribution,the characteristic value of fracture energy is equal to 66.0 N/m,the reliability is not less than 95%.

Abstract:The 750 kV structural gantry is a high and heavy load steel latticed structure,which is of vital importance in the 750 kV electric substation. It has high vulnerability during earthquakes. In this work,finite element models of 750 kV structural gantry with and without isolation layer are established by ANSYS. Dynamic time-history analysis are carried out by inputting seismic waves for these two models. The results show that by adopting suitable isolation bearing the structure gantry with base isolation has lower frequency. Apart from this,its top displacement response and pole stress have different degrees of reduction compared to those of gantry without base isolation. These conclusions indicate that it is effective to use isolation system,which has provided a basis for practical application of isolation technology in power tower.

Abstract:For the sand embankment water loss and soil erosion prevention situation,a model of sand soil surface anti erosion test was established to carry out rainfall scouring test. Based on the model test,anti-washout performance of different sand embankment slope protection layer was studied and erosion process of protection layer was analyzed. It is concluded that the mixture of sandy soil,bentonite and straw can resist rain erosion,ensure the smooth growth of plant seeds and facilitate construction.

Abstract:Degree of consolidation of soil has a great influence on the strength of the soil. Direct shear apparatu with constant strain rate is applied to investigate direct shear strength change law with the increase of consolidation degree by saturated kaolin at all levels of consolidation pressure. Results show that direct shear strength increases linearly with the increase of degree of consolidation at all levels of consolidation pressure. Then,miniature vane shear apparatus is performed to study the micro vane strength changing rules. At the same time,considering the size effect,a small diameter consolidation apparatus cooperated with miniature vane shear apparatus is developed. Studies show that miniature vane shear strength grows linearly with the increase of consolidation degrees.Comparing the above two kinds of test results,it is found that they have good consistency. It confirms that miniature vane shear apparatus studying the shear strength change law of saturated soft clay is feasible.

Abstract:In this paper,a new rheological component with unsteady viscous coefficient is proposed,then connecting the proposed nonlinear rheological component with the Poyting-Thomson model,a new nonlinear viscoelastic-plastic rheological model is established. The model can not only simulate the three stages of rock creep,but also has less model parameters. In this paper,the constitutive equation and creep equation of the model are deduced,and the identification method of the model parameters is discussed. Finally,the theoretical curves obtained by the nonlinear rheological model established in this paper and the sandstone creep test curves is compared and analyzed. The results show that the nonlinear rheological model established in this paper has good accuracy and rationality.

Abstract:In order to study the deformation and failure characteristics of deep soft rock roadway,taking the 13-1 coal mining roadway in some coal mine in Huainan mining area as an example,the similar simulation experiment of the deformation behavior of surrounding rock of deep excavation roadway is carried out. Based on the Block discrete element method,the numerical model of the surrounding rock of the deep mining roadway is established,and the deformation characteristics of the surrounding rock during the excavation are simulated. The results of the similar simulation experiment and numerical simulation show that the typical characteristics of the surrounding rock are as follows:opening floor heave > two sides move quantity > roof convergence. The influence of displacement of the surrounding rock under excavation disturbance is different,and the bottom plate is 3.5m,the roof is 2.45m,the two are 5.5m. The results of deformation control of deep roadway surrounding rock have important reference meaning.

Abstract:Based on a cross-tunnel bridge construction project,the effects of two factors -the distance between tunnel and pile (S) and the length of the pile (L) on the tunnel deformation are analyzed in the FLAC3D model. The results showthat the vertical displacement of the tunnel and S are approximately piecewise linear. In order to ensure the stability of the tunnel structure during the construction of the pile foundation,S should not be less than 6m;Relative position between pile and the tunnel is determined by the length of pile,the bottom of the pile should be avoided at the arch of the tunnel.

Abstract:In this paper,the ground penetrating radar is applied to the road detection,and the field test is carried out. The radar test results are compared with the results of core sampling. The location of the interface,the thickness of structural layers,and the existing diseases are analyzed. The Hilbert transform of radar raw data is used to obtain instantaneous amplitude,instantaneous phase and instantaneous frequency,then,the interface position of the road structure layer is emphatically analyzed. The results show that the ground penetrating radar can detect the thickness and the uneven settlement of the road structure layer. The accuracy and credibility interpretation of the radar image are improved by secondary processing.

Abstract:Freeze-thaw cycle test is carried out using sandstone taken from a tunnel in Altay. The sandstone specimen are frozen for 9 hours at minus 25 degrees,and melted for 5 hours at (20±2)degrees,which is the process of a freeze-thaw cycle. We take seperately this kind of cycle for 0,5,10,20,30,40,50,60,80 times for the rock samples. Then by taking the uniaxial compression test and the scanning electron microscopy,we obtain saturated sandstone's failure character、stress-stain curve、elastic module、poisson ratio under different times of freeze-thaw cycle,and analyze the physical and mechanical properties、the relationship between the fracture micro crack evolution and the times of freeze-thaw cycle. It turns out that with the increasing time of the cycle,the elastic module of the sandstone samples decrease on different extends,the peak stain becomes increasingly large,while the Poisson ratio increases firstly and then decreases,the area、length and width of micro crack increase on different extends,and the damage and failure of sandstone is continuously accelerating.

Abstract:As a new building material,EVG-3D type industrial prefabricated plate has excellent fireproof and heat insulation performance. This paper tests the performance of EVG-3D board. The results showed that:the unexposed surface single point of maximum temperature rise to 162.8 degrees,the average temperature rise to 139.3 degrees,which are consistent with the existing specifications. There is no smoke coming out for the EVG-3D plate specimens,and the specimens are integrated at the end of the experiment. From the experimental data and the experimental phenomenon,the EVG-3D board has good insulation and environmental protection performance,which provides an important basis for the use of EVG-3D board in our building.

Abstract:The train running on the track test line without derailment is the basic premise of track engineering scientific research test. In order to carry out the assessment of the derailment safety of the rail transportation comprehensive test line of Tongji University,this article measures the wheel-rail force of the rail transportation comprehensive test line,including wheel rail lateral force and vertical force,and then calculates the derailment coefficient and wheel load reduction rate through the wheel rail force. Results show,when the train passes at the speed of 20,30and 40 km/h,the average value of the wheel rail vertical force of the south rail is in the range of 54.91~56.14 kN,those of the north rail is in the range of 72.91~76.62 kN;t of the south rail is in the range of 5.77~7.86 kN,those of the north rail is in the range of 6.48~7.11 kN;The derailment coefficient are 0.096,0.104 and 0.113,wheel load reduction rate are 0.141,0.152 and 0.154. The derailment coefficient and wheel load reduction rate is less than the limit value,and has great safety margin,the scientific research test rail transportation line meets the requirements completely in the derailment safety evaluation.

Abstract:The gray clustering analysis method is used to evaluate the public bicycle service system in Handan area. On the basis of the obtained statistical data,considering the factors such as site spacing,resident travel mode and so on,the evaluation index system is establish. The public bicycle service system is analyzed from the overall layout to the vehicle condition itself. The results show that Handan City Public Bicycle Service System has a good effect and basically achieves the purpose of low cost and high efficiency,which is of great significance to enhance the people's choice of green transportation mode and perfect public bicycle service system.

Abstract:This article investigates the public seats situation in five shopping malls of Tianhe business district in the TaiKoo Hui,TEEMALL,OneLlinkWalk,Grandview Plaza and Parc Central. Comparin the domestic and foreign outstanding cases,and in the light of less quantity,scattered,discomfort,single form and other outstanding issues,this paper puts forward a systematic,diversified,convenient and humanized optimization scheme.

Abstract:The present article investigates the trunk canal of South-to-North Water Transfer Project constructed beneath the "Yu-ji" railway tunnel and crossing it. The three-dimensional numerical simulation FLAC3D is carried out to simulate the construction process,the results show that the canal structure is relatively stable when the distance between the top of the tunnel and the bottom of the trunk is about 32.24m. Besides the displacement becomes small when the ground loss rate is controlled at 0.5% or the overburden thickness is more than twice the diameters. It was also demonstrated that the displacement increases with the increase of ground loss rate,while it decreases along with the increase of soil thickness. The results of numerical simulation are compared with the empirical formula,and the results show that they are of high agreement.

Abstract:The Bayes method is based on the normal principles to analyze and evaluate the water quality of the Huangbizhuang Reservoir,the idea and calculation method of the improved Bayes method are also given. By using GB3838-2002 as evaluation criterion,the improved Bayesian model for water quality evaluation is established through selecting water quality monitoring data on dam,Huangbizhuang Reservoir. The evaluation results show that the model is suitable for Huangbizhuang reservoir water quality simulation,the water quality of Huangbizhuang Reservoir is mainly Ⅰ and Ⅱ grade,while it is worse in the rain season for water quality being Ⅱ grade,other months achieve Ⅰ standard.

Abstract:After the comparison between the thermal property parameters of the Hot Disk tester and the obtained test results of the field thermal response,it is found that the thermal conductivity measured in the laboratory is significantly different from the thermal conductivity of the field. During the design and selection of the ground source heat pump,the thermal conductivity of soil measured under heating or cooling power should be determined,which can be the selection basis.

Abstract:In order to solve the oil remaining serious,injection and extraction effect issues in Huachang field of Fushan sag,combined with the actual situation in the region,using the core data,logging data,layer,interlayer and plane heterogeneity of Huachang field flow for a period in Fushan oilfield were studied. The results show that the coefficient of variation of permeability,the coefficient of the breakthrough and the range of the reservoir in the first section of the flow field are stronger,and the mean coefficient is lower. From the interlayer distribution,the study area flow reservoir Ⅱ and IV oil group is relatively strong;the study area is mainly affected by the strong reservoir heterogeneity,sedimentary structure,permeability heterogeneity,interlayer distribution and non control factors such as particle size rhythm;interlayer heterogeneity is mainly affected by the thickness,sandstone thickness and interlayer thickness. Large differences exist in different horizons. The plane heterogeneity is influenced by the distribution of sand bodies and sedimentary microfacies. It is concluded that the oil reservoirs in the study area are favorable for the remaining oil distribution.

Abstract:This article is guided by the theory and method of sedimentology and petrology,based on the data of field outcrop,drilling core,logging curve and other data,and combination of macroscopic analysis and microcosmic study. Combining with the research results of other areas in North China Basin,the sedimentary facies type and coalite effect of coal in the coalfield have been discussed. The results show that the coal strata of Hanxing coal field deposites from the Carboniferous to the Early Permian,and experiences the evolution of the sedimentary environment in the tidal flat and shallow water delta. The shallow water delta of Permian develops the stable and recoverable 2 Coal seam.

Abstract:Aiming at the shortage of the existing MASK dodging algorithm,a gradient stretch algorithm for MASK image is proposed. Experiments show that,comparing with the 2% linear stretch and contrast parameter stretching,the algorithm can solve the problem of uneven distribution of remote sensing image brightness. At the same time,it canguarantee the sharpness of the image,enhance the contrast of details,reach good effect of dodging.

Abstract:In this paper,taking Beijing as the research area,the Python language is used to obtain the real-time traffic data provided by the Baidu map API at the sample point location,then,the sample points are transformed into reachability surface by spatial interpolation,and the surface data is graded. Finally,we get traffic data. Through the Beijing bus credit card data to obtain the space-time circle for the evaluation of confidence,as a basis the two modes of driving and public transport under the peak and non-peak space-time circle are divided. The results show that:①The obtained traffic data has a great correlation with the credit card data,which shows that the real-time traffic data method can be obtained through the Baidu map API.② Compared with the traditional traffic circle acquisition method,the data obtained by Baidu map API is more accurate and more real-time traffic circle information;③ Compared to the driving mode,the Beijing public transport mode traffic circle is in the bias-type extension of the poor support;④ Public transport mode takes into account the distance and time,which will provide a basis for the future study on the balance of the distribution of public transport in the city.

Abstract:The virtual prototype model of ADMAS is established,and the dynamic simulation is performed,the dynamic characteristic curve is obtained. The simulation results show that the operating process of the working arm is relatively stable. At the same time,the finite element analysis is carried out under two kinds of dangerous conditions,the stress distribution and strain distribution are obtained. According to the stress curve of the maximum stress position,the maximum load is used to load the middle arm and the lower arm respectively,static analysis is made. The results show that the maximum should still meet the requirements by the maximum load point,which provides a reference for optimizing the design of aerial vehicles.

Abstract:In order to improve the universality of the surgical robot,this paper analyzes the workspace and operation requirements of different minimally invasive surgery,and a universal surgical robot with 8 degrees of freedom has been designed. A multiobjective optimizing function with kinematic index and dynamic index has been constructed. The genetic algorithm is used for the optimization process and the structure parameter with high dexterity is obtained.

Abstract:In this paper,an accurate micromagnetic model is built for CoPt-TiO₂ (16 nm)/Co-TiO₂(4 nm) exchange coupled magnetic recording media. Based on the microstructure,the effect of the magnetic parameters such as the anisotropy,the saturation magnetization of the soft layers on the magnetic properties of the media is investigated. In the M-H loop of CoPt-TiO₂ (16 nm) hard layer,the easy magnetization axis coercivity is 6.1 kOe and the squareness is 0.98. In the exchange coupled media,the coercivity decreases from 6.1 kOe to 4.9 kOe when the thickness δ of the soft layer increases from 0 nm to 4 nm. Meanwhile,we also found that the coercivity decreases when the anisotropy is lower and the saturation magnetization is larger in the soft layer.