Abstract:In order to investigate the hysteretic behaviors of opening cold-formed thick-walled steel members under the axial cyclic loading, three cold-formed steel columns were tested. On the basis of compared with the test results, a finite element method (FEM) in ANSYS was established. The influence of width-thickness ratio (h/t) rang from 25 to 90 for web and slenderness ratio about the weak axis y (λ_y) rang from 30 to 90 of such members were investigated by FEM. Analysis results indicated that the width-thickness ratio and the slenderness ratio about the weak axis y are the most important factors to affect the hysteretic behaviors. So, the cold-formed steels which with great width-thickness ratio (h/t) and great slenderness ratio (λ_y) should be avoided in designing, because they will lead to poor seismic performance.

Abstract:Based on the assumption of small deformation, this paper derives The torsional displacement function of centrally compressed stiffened cruciform column with initially twisted imperfection, gives its unified forms and discuss its property. A finite element model is developed and verified against the theoretical result. The study shows that results of FEM were generally in good agreement with the theoretical results when axial force is smaller then 0.4Af_y. The is obvious second-order effect between axial force and torsional displacement. The initially twisted imperfection has negative effect on the centrally compressed stiffened cruciform column, and the degree of the influence has positive correlation with its amplitute.

Abstract:This paper takes HeFei Metro Line1, Line2 subway transfer station deep excavation engineering as the background, using FLAC^3D to establish the model, simulating the process of excavation, what's more,the supporting systems of deep foundation pit are analyzed, considering the interaction between supporting structure and soil, calculating and analysing of the diaphragm wall internal forces and deformation, and by comparing the calculation results of various working conditions, the distribution law of the unsymmetrically loading and irregular diaphragm wall of internal force and deformation were obtained. The calculation and analysis results showed that the main stress of deep foundation pit supporting structure of irregular is bigger than the straight arm's, and the stress concentration phenomenon is more obvious, the horizontal deformation is larger than the arm's under the same conditions, the force and deformation for unsymmetrically loading and irregular is worst case in deep pit. The results of the study which is for future subway station deep foundation pit engineering design, construction provide the basis necessary reference.

Abstract:Based on laboratory model test,the promotion in effect and law of the dissipation process of excess pore water pressure by permeable pipe pile.Compared permeable pipe pile with normal pipe pile model experiment,the evidently positive effect on the dissipation of excess pore water pressure could be found in permeable pipe pile model test.The impact scope of the soil mass in the middle and lower part was the depth direction,decreasing along the horizontal direction..Permeable pipe pile in the dissipation of excess water pore pressure had the most obvious effect on the early period,greatly speeding up the construction progress. It is found that the excess pore pressure evidently reduced in the soil around the pile at the initial time of drainage pile completed. In the process of pile driving construction, the permeable pipe pile improves the construction schedule and reduces the influence on the surrounding environment.

Abstract:Aiming at the shortages of seismic design factors for retaining wall, the combination of pesudo-static and horizontal slice methods were used to analyze the seismic stability of reinforced soil walls, and the effect of various parameters including angle of internal friction, horizontal seismic loading, cohesion of the backfill, surcharge loading and inllination angle were examined. The results show that:The stability of a reinforced soil wall increases with the increase of horizontal seismic loading and surcharge loading, while it decreases with the increase of angle of internal friction and cohesion of the backfill. Under the same conditions, the inclined wall is more stable than the vertical wall.

Abstract:The reliable and efficient identify method of rock creep model was discussed, in order to reduce the onerous calculation of parameter identification of rock creep model. Take M-K creep model for example,Algorithm was writed use Matlab and then it's spun off the Matlab by mean of COM.The object-oriented visualization software was writed based on VB. The results suggest that the software used on calculation of parameter identification of rock creep model show up more efficient and worked well, which provide fast process method that can be used for reference in parameter calculations of the others rock mechanics.

Abstract:The stability of high rock slope which contained fracture zone and the reinforcement effect of anti-slide pile were evaluated and studied based on a practical case of an engineering slope in the area of Xiuyan Xiaohuling.The calculated parameters were obtained via large direct shear strength tests in the local field and laboratory tests,at the same time,the stability and safety factor were analyzed and obtained through numerical analysis based on Strength Reduction FEM. Result indicates that the fracture zone is the key reason to the influence of the slope stability,the area of max shear strain is similar to fracture zone's shape in slope,and the slope belongs to unstable slope in nature status because of the safety factor was 1.01,the safety factor was increased to 1.72 after using anti-slide pile,safety factor of slope along with the andvalue of fracture zone increases in a certain range.

Abstract:Soil-water characteristic curve and hydraulic conductivity function are determined based on VG model, and then by way of constructing finite element numerically analysis model, both seepage-stress coupling analysis and uncoupling analysis which only considering seepage are conducted by using finite element software SIGAM/W and SEEP/W respectively, factors of safety is calculated by software SLOPE/W using seepage field and stress field from coupling analysis and uncoupling analysis and analyze stress and strain to research the principle of coupling effect on slope stability. The results show that the rate of rain infiltration advance is faster due to seepage-stress coupling effect which results in faster loss of suction compared with uncoupling analysis. Rainfall has negative influence on slope stability,the factors of safety from coupling analysis is lower than that from uncoupling analysis, thus the influence of coupling effect on slope stability cannot be neglected. Stress concentration appears in surface layer and stress concentration belt appears at the depth of wetting front on the condition of rainfall infiltration, which means that slope is prone to shallow failure. Slope toe is the first region to failure because horizontal displacement in slope toe is higher than that in slope top.

Abstract:For slope stability influence factors of uncertainty, this article is based on spencer method, considering the effects of several parameters on the slope stability are random, reliability analysis of the slope stability is put forward method of joint distribution of random variables.Soil in this paper, we define the internal friction Angle, cohesive force, the bulk density for a normal distribution function of random variable and the coefficient of horizontal seismic with exponential distribution function of random variable, called the normal distribution function and exponential function in MATLAB to build under the condition of seismic reliability model, analysis the influence of the sensitivity of the parameters on the safety coefficient, the results show that the slope Angle of internal friction in the biggest influence on side slope.

Abstract:In this paper,considering the effect of vegetation roots changes along with the depth of soil slope, establish finite element model, using the strength reduction method,,focus on clay soil two kinds of soil slope and whether rain or not, to analyze the effects of different vegetation roots on the soil slope stability. The results showed that the vegetation roots can improve the safety coefficient of slope effectively; change of slope angle does not affect the raising of vegetation on the slope safety coefficient of slope; in the rainfall condition, the stability will be reduced to a certain extent, but the roots still can improve the relative safety coefficient of slope.

Abstract:Lenggu hydropower station is located in alpine valley region of Yalong River. Due to the complex geological environment, the stability problem is sever and it is influenced by numerous factors. With slope safety factor chosen to be the index, the unit weight, cohesion, internal friction angle, water level and seismic coefficient were selected to be the factors. Then, the numerical experiments based on uniform design were done and the results were analyzed with grey correlation theory. The result show that the sequence of magnitude of correlation with slope stability is:internal friction angle > water level > seismic coefficient > cohesion > unit weight.

Abstract:Heavy tamping method is a kind of important method of rubble bed tamping in the construction, the heavy hammer tamping energy is an important indicator of impact compaction hammer effect, the hammer tamping energy can be influenced by hammer type, flow resistence, drop distance and other effects. Therefore, on the basis of fluid dynamics. First of all, establish the calculation model of the hammer in water movement, analyse the hammer flow resistance in the process of hammer in water movement, and then through the indoor shrinkage scale test, analyse the water movement law of the cylindrical and cone hammer,obtain the experiential tamping hammer water flow coefficient value. Finally, analyse of the different geometric rammer, different distance to the effect of compaction effect. The results show that a cone type tamping hammer and cylindrical rammer compared. Because of the chamfer of a cone type hammmer, flow resistence coefficient is smaller in water and the value is about 1.0. under the action of the same tamping energy, different types of hammer has difference in 5% on the rubble mound foundation compaction effect.with a hammer in different falling distance, the greater the falling distance is,the greater the amount of settlement of riprap foundation bed is, the bigger the compaction stress is. but rubble mound foundation settlement has a limit value. The research results can provide reference for the selection of hammer shape under the process of compaction.

Abstract:The scheme determination of foundation by field experiment to be sure, in order to accurately determine the scheme, based on the shear wave velocity method. Basis of komsomolsk jiangxi province south lake area new town of geotechnical engineering, the local field soil stiffness) (shear wave velocity test, collecting data through the three waveform record. By communication with computer, and transmit data from the instrument to the computer, the shear wave velocity of soil is obtained after processing, in turn, determine the type of construction field, the result is a characteristic value should be with single pile vertical bearing capacity of the single pile vertical static load test to determine, the number of piles in the same conditions of not less than 1% of the total, and not less than three, the group should be considered in the design of pile caps group effect of pile caps. Therefore, reasonable use of shear wave velocity test, can accurately determine the foundation plan.

Abstract:The superimposed shear wall is a new assembly-type RC structure, it has been found more and more applications in building construction because of its adaptation to building industrialization. There are two common forms of superimposed shear wall:the superimposed shear wall with prefabricated boundary element and with cast-in-situ boundary element. The superimposed shear wall with prefabricated boundary element is more convenient to the construction than superimposed shear wall with cast-in-situ boundary element. The superimposed shear wall with prefabricated boundary element is of much more practical value in actual production. The structural improvement of superimposed shear wall is proposed. A simulation with OPENSEES finite element software was given to analyze the behavior of improved superimposed shear wall. The analysis shows that the improved superimposed shear wall not only has higher ultimate bearing capacity than unimproved superimposed shear wall, but also increases shear capacity of the interface of new-to-old concrete.

Abstract:According to the example of the combination of three corrugated steel webs(50m+80m+50m) across PC continuous box girder bridgewhich has been built and used.According to the bridge after the completion of operations, the Midas/Civil Software finite element modeling was used to make inspection and review of the bending and shear, crack deflection and strength three kinds of the most adverse effects (short-term effects of the combination, and the standard combination of values and ultimate limit state the basic combination).The results show that the structure can well meet the requirements specification and design documents when its finite element model is in condition of the three most adverse effects.

Abstract:Based on an existent passive office building in cold areas, two different models were set up according to actual condition and domestic design standard by using the eQUEST software. Ten cities located in different provinces in North China were selected to compare the energy consumption of air conditioning. The results show that the passivhaus have almost the same energy consumption in summer with the normal buildings, but in winter, the heating energy consumption of the passivhaus has great decline. On the comprehensive energy consumption of air conditioning, Taiyuan has the largest energy saving potential. In Taiyuan and Harbin, the passivhaus's air conditioning energy consumption is 54.16% and 34.06% less than the domestic normal buildings respectively. Passive office building has great potential for energy saving in northern China.

Abstract:In order to investigate the environmental pollution of heavy metals in coal gangue, samples of the coal gangue and shallow groundwater in surrounding areas were collected in Gongyi City, Henan Province. The coal gangue samples were treated by leaching experiment first. Then the contents of metallic elements in groundwater and treated coal gangue leaching water samples were measured by inductively coupled plasma mass spectrometry (ICP-MS). The results showed that the contents of Cr and Pb were high in coal gangue, and the amount of the metallic elements increased as the coal gangue stacking over time with variable dissolution trends. The contents of most metallic elements in shallow groundwater were higher in the collapsed area than in the non-collapsed area, except for Cr and Sr. The contents of Cr and Cu in shallow groundwater samples from collapsed area, and Cr from non-collapsed area were high, as 17.6, 59.4 and 22.8 g/L, respectively. Based on the leaching characteristics, and comparison between the contents of metallic elements in the collapsed and non-collapsed areas, we suggested that the high contents of Cu and Pb in shallow groundwater in collapsed area were closely related to the coal gangue dump.

Abstract:As a two dimensional nonlinear transfusion model, the "stope-neighboring pillars-goaf" micro-circulation phenomenon was numerically simulated with PDE tools in MATLAB. The formation of the phenomenon and its influence on coal spontaneous combustion was also studied. The results show that the "stope-neighboring pillars-goaf" micro-circulation causes the periodic variation of relative pressure and gas composition in mining face goaf, which is called "goaf gasp". The research gives a theoretical significance for large-area fire prevention and extinguishing.

Abstract:The Kalman filtering is easily affected by the gross error and it will cause larger distortion of the result. To overcome this problem, an adaptive robust Kalman filtering was proposed. It combines the advantages of adaptive Kalman filtering and robust Kalman filtering by using the adaptive factor and the robust factor. And the improved two segments Huber function was designed as the robust factor, the two to three times observation noise error was designed as the gross error determination standard respectively. Compared the result of Kalman filtering and adaptive robust Kalman filtering, the latter could effectively resist the influence of abnormal observation to the state estimation, and can improve the stability and availability of the filtering estimation significantly.

Abstract:Based on the GC-MS, the variation of organic matter origin, deposition environment and thermal maturity of hydrocarbon source rocks were systematically discussed. The distribution of tricyclic terpane is normal distribution with the main peak of C₂₃, high content C₂₄ tetracyclic terpane and a predominance of C₂₇ααα20R sterane over C₂₉ααα20R sterane with asymmetry "V" distribution indicates that the organic material of source rocks are higher terrigenous plants mixed with lower aquatic organisms. The main peak of hopanes is C₃₀ hopane with the distribution of C₃₁-C₃₅ hopane decline as a ladder and the tricyclic terpane/hopane ratio is high shows the lacustrine facies characteristics. The Pr/Ph value (0.44~0.49) and gammacerane/C₃₀ hopane value (0.32~0.38) indicate that source rocks are developed in brackish water reductive semideep-deep lake environment. The maturity parameters of C₂₉ααα20S/(20S+20R), C₂₉αββ/(ααα+αββ) and C₃₁αβ22S/(22S+22R) have reached the balanced endpoint value of isomerization, indicating the source rocks stay in mature-high mature stage during the thermal evolution.

Abstract:At present, the experiment methods of low temperature nitrogen adsorption in shale reservoir pore structure have been widely used. But the interpretation of the adsorption stripping curve about the type of shale reservoir microscopic pore structure is chaos. Based on this, the mechanism and characterization of low-temperature nitrogen adsorption experiments in shale microscopic pore reservoir was emphatically discussed, and the typical cryogenic nitrogen stripping absorption curve was explained in detail. Then, the evaluation standard system of low-temperature nitrogen adsorption in shale reservoir microscopic pore structure was developed. Engineering practice demonstrated its feasibility, and the study gives reference to the evaluation of shale and coal reservoir pore structure.

Abstract:To study the propagation rule of blast shock wave outside tank and its impact on the safety of storage tank, the software LS-DYNA was used to build numerical model of dynamite-storage tank, and the air blast numerical calculation was performed. The study analyzed the attenuation relation of shock wave overpressure and the dynamic response of the tank. The reliability of the model was verified by contrast with the empirical formula. And the further amendment for numerical simulation results was made. The results are as follows: When shock wave moves to burst surface center, principal stress in 10ms quickly reaches maximum value, and then decreases rapidly and continuously oscillated; The facing blasting center first produces larger tensile stress, the destruction of concrete tank belongs to brittle failure; When the proportion distance is greater than 1, overpressure formula can better fit the attenuation law of overpressure; While the proportion distance is less than 1, the error of the overpressure formula is large. The amended overpressure calculation formula can be used as a reference tank blast-resistant design.

Abstract:An algorithm for identification of linear time-invariant system impulse response was studied by using m-sequence under the condition of multiple sampling within one clock cycle series. An expression described impulse response sequence with the m-sequences' cycle, amplitude and the sampling rate was derived. For this purpose, the bipolar m-sequence signal autocorrelation property was sampled uniformly, and the unified expression in whole cycle was given and was introduced into Wiener-Hopf calculation to obtain the system's impulse response. Then, the system's impulse response was expressed as the sequences of the input signal and output signal with the cyclic shift matrix. Simulation on the MATLAB platform proved the correctness of the algorithm.