最新刊期
卷 31 ， 期 6 ， 2009
- 摘要：A new type of wind turbine tower,Variable CrossSection Frame wind turbine, was proposed. With Fortran language and binarycoding method of Genetic Algorithm (GA), calculation algorithm of varying crosssection frame wind turbine was developed base on practical project. Upon the optimization algorithm, sectionsize and shape optimization of wind tower was carried out. By the finite element software, with userdefined beam element parameters, an optimization model was proposed for traditional singlepipe tower. It was found that compared with singlepipe tower, frame wind turbine has quite a lot advantages such as relative higher first natural frequency and stiffness, relative lower foundation quantities, easy to be carried and constructed and so on.2333|1521|1更新时间：2023-11-28
- 摘要：Excessive creep camber of prestressed concrete bridge would result in risk on the traffic safety in highspeed railway. To control creep camber of presstressed concrete bridge, a new twiceprestressed technology was proposed to presstressed concrete beam. Four twiceprestressed simply supported box girders with different prestressed degrees were designed as an example. Its section stress, strength and crack resistance in different construction stages were analyzed. Compared the creep camber between conventional prestressed simply supported concrete beam and twiceprestressed simply supported composite beam with the same prestressed steels, it was shown that twiceprestressed composite beam has a smaller stress gradient. And the creep camber decreased approximately 40% to 60% with building height reduction, as well as some 10% energy saving and some amount of concrete.2123|1092|1更新时间：2023-11-28
- 摘要：A new steelconcrete composite structure was proposed which composed of steel box beam, PC beam and PBH Shear connection. Bend test was carried out for the performance study of deformation and stress. It was found that Material advantages of steel and concrete were fully used and crack of concrete and local instability of steel box were avoided. And the deformation between steel box and concrete can be smoothed with PBH shear connection. As the calculated values showed good agreements with the test results, the proposed formulas can be reliably applied to the practice analysis. With the different parameters analysis, mechanic performance of the composite was obtained.2001|1197|3更新时间：2023-11-28
- 摘要：Isolation technique was not only applied for middle or low buildings, but also recently it was applied to highrise buildings. For highrise buildings, multiorder vibration should be considered for upper structure isolation and bend deformation should be taken into account in gross deformation because of large height to width ratio. On the basis of previous studies, calculation method of equivalent model for regular isolated structure with bendshear deformation characteristic was proposed according to equivalent criteria after the analysis for some model structures. With the proposed model, handwork calculation of earquake response for isolated structure can be simply completed and design efficiency of isolation structure was improved. Based on the case studies, the equivalency of proposed model was approved.2116|1031|0更新时间：2023-11-28
- 摘要：According to characteristics of largespan structures, a methodology was proposed to analyse the equivalent static wind load for multiple targets of China’s National Stadium. The general principles were, taking dominating eigenmodes and dominating vibration modes as basic vectors to express equivalent static wind load for multiple targets; and then obtaining optimization coefficient with least square approximation method; thus, obtaining the equivalent static wind load for multiple targets. Upon the case study, it was found that background response was much more than resonant response for all of the wind directions with most unfavorable at 0 degree and 270 degree directions. And structural response of all nodes and all supports under a single equivalent static wind distribution were in good agreement with peak values under actual dynamic wind loads at the same time.2406|1995|2更新时间：2023-11-28
- 摘要：Mises strain from plastic theory was put forward to be the fracture criterion of corroded steel strands. By tension tests of 14 corroded steel strands with chloride, 46 breaking wires were obtained with the mean tension stress and the geometric configuration of the pit. Based on the above, the fracture resistance of each breaking wire was simulated by the finite element software ANSYS. And the simulation results were addressed to analyse the characteristics of fracture resistance with SPSS software. It was found that at the significance level of 0.05, both normal distribution and logarithmic normal distribution were not refused for the fracture resistance distribution. Hence, the distribution models (percentage distribution function) were obtained under the two distribution modes.1787|1463|3更新时间：2023-11-28
- 摘要：Based on Reynolds Averaged NavierStokes Equations(RANS)standard kε model, realizable kε model, RNG kε model and SST kε model, the 3D steady wind flow field around standard high building CAARC in atmospheric boundary layer was numerically simulated with software Fluent 6.3. And upon the comparison with those from wind tunnel test, it was found that numerical simulation was a feasible way to study the wind flow around high building and the distribution of wind pressure in the building’s surface. The four proposed models can reach the accuracy from the actual demand. Furthermore, it was also shown that, the numerical results were approximate to those from wind tunnel tests in the windward while between those from NPL and TJ2 tests in the side and leeward. The pressure on the windward surface was positive with the maximum at 2/3 height and the minimum on the sides and the bottom. The pressures on the leeward surface and two sides were negative. There were little differences among the results of the four models.2847|1145|7更新时间：2023-11-28
- 摘要：Cohesive soil of the interactive marine & terrestrial deposit along the north side of the Yangtze River estuary has poor physical properties in which water content ratio is approximate or excessive to liquid limit and void ratio is approximate or excessive to one. With free piston thin wall sampling technique and vacuum freeze drying method, undisturbed and remolded samples in different consolidation stress were made. And the microstructural and parameters were analyzed. It was found that the microstructure change and macromechanic properties were in good agreement. And micromechanism of the abnormal correspondence was found between the poor physical properties and good mechanic characteristic indexes of structural cohesive soil.2393|1203|3更新时间：2023-11-28
- 摘要：For most evaluating methods of engineering rock mass, the integrality index is an important assessment factor. However, sometimes the value of integrality index would be more than 1.0 because of unloading effect of rock samples and differentia of frequency between the measurements of rock samples and rock mass. In order to solve this problem, unloading index and frequency correcting coefficient were put forward to revise the integrality index. Moreover, the BQ evaluating method proposed in the national standard (GB 50218-94) was improved with the revised method. With the case study of the project of water sealed underground oil tank in Huangdao, it was found that the quality of rock mass in the site was grade I or II.2196|1167|1更新时间：2023-11-28
- 摘要：To investigate the seismic behaviors of frames in framewall structures (dual system), which may be different from those of frame structures, two framewall structures were designed conforming to current Chinese design codes. One is a twentyfourstory building on the Zone of Fortification Intensity 8 (0.3g), and the other is a thirtystory building on the Zone of Fortification Intensity 8 (0.2g). Then inelastic dynamic response analyses of the two structures were conducted with series of inputs of ground motions in a rare earthquake level. The seismic behaviors of the two structures were investigated preliminarily. It was found that the columns and beams of the frames in the framewall structures did not experienced yielding under strong earthquake, while coupled beams in walls were the major energydissipation elements with their postyielding plasticity. And the bases of some walls formed hinges as well. The reasons for the frames of dual system remained nonyielding states were analyzed and discussed from the aspects of their favorable loadcarrying state and strengthening measures for them in dual systems in Chinese design codes. A preliminary proposal was made that it may be feasible to loosen moderately some seismic fortification measures concerning the frame in the dual system with a height exceeding 60m on the Zone of Fortification Intensity 8.2483|1338|3更新时间：2023-11-28
- 摘要：1/20 scale model test and full scale field test were carried out to study the critical velocity for fire ventilation in horizontal tunnels. Combined with the test results, smallscale test results by Jae and fullscale test and simulation by Hu, a semiempirical model was developed to predict the longitudinal critical velocity for tunnel fire ventilation. Compared with the predictions of the proposed model and other models using air as fire source, it was found that the predictions by Wu and Barker was underestimates.2014|1102|4更新时间：2023-11-28
- 摘要：Wind hazard damage estimation was addressed for light steel industrial buildings which were the typical wind vulnerable structures in southeast coastal cities. With parametric analysis of wind damage and the structural failure features, the envelop elements and the connecting elements were determined as the pivots of the damage analysis. Upon the consideration of the coeffect of exterior wind pressure, windinduced internal pressure and windborne debris damage, a typhoon load model was proposed. And with the calculation method of the element resistance from the regulation, the procedure of the damage estimation was described and the damage classification of industrial buildings was specified with detailed indicators. Finally, the proposed method was approved with the actual data of typhoon CHANCHU (0601).4857|3133|6更新时间：2023-11-28
- 摘要：The effect of water to cement ratio, fiber types and content, cement types on the bending performance of the extruded fiber reinforced cementitious board were studied. And it was found that polyvinyl alcohol (PVA) fibers can significantly improve the ductility of the board compared with polypropylene (PP) fibers. As PVA fiber content achieved 1.7%, the strain hardening and multiple cracking were occurred on the extruded board, while strainsoftening were shown on PP fiber reinforced cement board. The difference between the two kinds of board was from the differences of the mechanical properties of the two fibers. In addition, taking the fiber reinforced extruded board as base, the ultimate bending strength, as well as and the corresponded deflection and the resistant to chloride iron penetrating, was improved for a composite beam with fiber board and concrete compared with those of traditional concrete beam.2170|1258|2更新时间：2023-11-28
- 摘要：Jiaozhou Bay subsea tunnel is the second selfbuilt tunnel in China with the designed service life over 100 years. On the basis of service environment of subsea tunnel concrete and the durability experiments of concretes, the service life prediction model considering chloride diffusion, carbonation and bending loading was proposed. The key durability coefficient of lining concrete in subsea tunnel was investigated. And the function of chloride diffusion coefficient and rebound strength of concrete was proposed. Moreover, the chloride content in concrete varied with service time and the service life of lining concrete for subsea tunnel was predicted with the proposed service life prediction model. It was found that the value of varied cover thickness was from -4(6) to 15 mm. The chloride diffusion coefficient mean value of lining concrete in standard curing was 2.1(2.7)×10-12m2/s. And the initial chloride content in concrete was less than 0.35kg/m3. The relationship between chloride diffusion coefficient and rebound strength could be regressed to linear relationship, and the calculated chloride diffusion coefficient of lining concrete was varied from 1.5×10-12m2/s to 3.5×10-12m2/s. The predicted service life of lining concrete for Jiaozhou bay subsea tunnel was more than 100 years according to proposed model.1575|859|4更新时间：2023-11-28
- 摘要：External shading system of windows can reduce the indoor solar heating gain. Previous studies did not take the change of diffuse radiation into account. However, in fact, the change of diffuse radiation should not be neglected because of the existing of shading devices. Especially to those blinds, most direct radiation can be shaded while most diffuse radiation can reach the indoor space. Thus, a detail calculation model was established for diffuse radiation. With the analysis of the thermal characteristics of direct solar incidence on the blinds, a mathematic model was developed to calculate the transmittance and reflectance of the solar diffuse radiation. Based on this model, the relevant algorithm was developed.1812|1091|8更新时间：2023-11-28
- 摘要：By parametric analysis of direct solar gain on building walls, equivalent decomposition was carried out for the direct solar gain. Upon this, building orientation transformation rules were proposed. Two types of buildings with different lengthwidth ratio in Shanghai were taken as case studies with simulation. And comparison curves of different orientation between transformation ones and the formers were obtained. It was found that cooling loads of transformed buildings were in good agreement with those of real buildings, which implied that the essential of orientation’s influence on cooling load was areas alteration of walls and windows in different orientations. By the transformation rules of building orientation, community buildings with different orientation can be transformed into those with the same orientation to predict community cooling loads, eliminating influences of the factor of building orientation.2394|1519|0更新时间：2023-11-28
- 摘要：Polyferric silicate sulfate flocculants were prepared by using tetraethylorthosilicate and polyferric sulfate as raw materials. The relevant mechanism was studied. And it was found that since tetraethylorthosilicate had the characteristics of slow hydrolyzation, the reaction was easy to control. Thus, the products had a good repeatability, which was better for the study of algae removal. The optimum preparation conditions of polyferric silicate sulfate were determined by using orthogonal design, in which Fe/SiO2 mole ratio was 1, polymeric temperature was 50 ℃ and polymeric time was 60 minutes. Furthermore, the optimum conditions of removals algae were determined as well, in which when the pH of raw waste water was 11.0, the dosage of PFSS prepared in the optimum condition was 24.1mg/L and the dosage of preoxidation was 0.7mg/L.2405|1054|4更新时间：2023-11-28
- 摘要：An experimental model was made on the improvement of sources water quality through the construction of a special riverine ecosystem using ecological embankments, which consisted of porous concrete, microorganism and hydrophytes. It was found that, with six day as retention time (RT), the removal rates were 20.9% for CODMn, 13.4% for UV254, 81.4% for NH+4-N, 96.8% for NO2-N and 67.7% for TN. In contrast, in the control pool with hard embankment, the removal rates only reached 9.6% for CODMn, 5.0% for UV254, 70.8% for NH+4-N, 42.4% for NO2-N and 34.6% for TN. Through coordination of all constituent elements of special aquatic ecosystem such as porous concrete, hydrophytes and substrate microorganisms, organic pollutants and nitrogen can be removed effectively.2247|1177|1更新时间：2023-11-28
- 摘要：The high grade gray water was pretreated by biologic contact oxidation on load of 0.72 KgBOD5·m-3·d-1, and then posttreated by constructed wetland. On the basis of experiment, it was found that: Totle nitrogen (TN) was the restrictive index of the combinational technique. To meet the reclaimed water quality standard and reuse for waterscape, the peak hydraulic load of constructed wetland was 0.50 m·d-1 in summer (30~36 ℃), and 0.33 m·d-1 in winter (8~12 ℃). And the load ratio of the peak hydraulic under the summer and winter conditions was 3:2. With the experimental results and reclaimed water quantity requirements in different seasons of buildings, treatment scale can be determined.1915|960|0更新时间：2023-11-28
- 摘要：The dissolved oxygen distribution and nitrogen removal effect in different structures of wetlands were investigated by two groups of comparison experiments (vertical flow with horizontal flow; singlestage with threestage horizontal flow). It was found that the different hydraulic flow patterns in different structures of wetlands would result in different oxygen distribution and nitrogen removal effect. The special structure design and hydraulic flow pattern of vertical flow wetland were favorable to its dissolved oxygen distribution, which could increase 0.17 mg/L in local area than that in horizontal flow wetland. The nitrogen removal effect of vertical flow wetland was better than that of horizontal flow wetland in the same operation conditions. The removal efficiency of NH+4-N and TN could increase 9% and 5% respectively in vertical flow wetland than that in horizontal flow wetland. Because of reaeration in contacting channels of threestage wetland, the removal efficiency of NH+4-N and TN reached 66% and 71% respectively, which improved 8% and 5% respectively than that of singlestage wetland. In addition, threestage wetland could keep higher nitrogen removal effect even in low operation water level, and the range of its best hydraulic retention time(HRT) was extended.2644|1188|7更新时间：2023-11-28
- 摘要：The removal effect of 2,4,6trichlorophenol (TCP) by five kinds of activated carbon (GAC0、GACH、GACF、GACF1M1、GACF1M3)were investigated. And it was found that the adsorption capacity was 160,178,207,194 and 238 mg/g, respectively. With the further study of GACF1M3’s performance, it was shown that adsorption capacity increased with initial concentration increasing, and decreased with temperature increasing. When the temperature was changed from 30℃ to 45℃, the removal rate would reduce slightly. The dosage increased from 10 mg to 500 mg, the removal effect improved significantly. Acidic condition was more favorable for the adsorption of TCP. Upon the analysis of the reaction kinetics, it was found that the reaction could be simulated with pseudosecondorder kinetic model. With XRD and SEM, the main metal oxide composites of GACF1M3 were Fe3O4、Mn3O4、FeOx(MnO)1-x.1821|1003|2更新时间：2023-11-28
- 摘要：The feasibility using zeolite filter column was investigated to remove phthalate esters from drinking water through a bench scale study. Dimethyl phthalate (DMP), dibutyl phthalate (DBP), dioctyl phthalate (DOP) and di(2ethylhcxyl) phthalate (DEHP) were selected as the representative target contaminants, and the each PAE influent concentration of the zeolite filter column is about 20μg/L~100 μg/L. The four sorts of PAE were determined with the high performance liquid chromatography(HPLC) at the condition of the zeolite filter column’s empty bed contact time (EBCT) from12 min to 18 min. The results indicated that the removal efficiency of total PAEs(contain DMP、DBP、DOP and DEHP) was fluctuating within 24.7%～33.8%;with the increase of the influent concentration, the removal rate of DMP and DBP decreased while DEHP and DOP increased.2208|1010|7更新时间：2023-11-28
- 摘要：In order to improve the hydraulic permeability of wastewater infiltration system, two installations were designed with two with layers of red soil and cinder. At the load of 10 cm3/(cm2·d), the average removal efficiency of COD, TP, NH+4-N were different fillers for treating domestic wastewater at laboratory.1 installation was filled with layers of red soil and sand, while 2 obtained 91.1%, 97.6%, 48.7% and 80.1%,respectively by 1 installation; and 94.9%,98.3% and 89.0%,respectively by 2. The average effluent concentrations of nitric and nitrite were 54.7mg/L and 0.09mg/L by 1 installation; and 60.3mg/L and 0.15mg/L by 2. It was found that the removal efficiency of COD,TP and NH4+-N by 2 installation were better than those of 1, whilst 1 installation was more favourable for the removal of nitric and nitrite. The results further implied that layeredfilling can make good use of its filling performance. The hydraulic permeability of wastewater infiltration system and the removal of pollutants can also be effectively improved.4483|3308|4更新时间：2023-11-28
- 摘要：A new method of image segmentation based on neural network was proposed to extract the cracks image, with which it could overcome, in some extent, the dependence of the background image and reduce the pseudopoints and pseudoregions. The measurement accuracy can be improved compared with that from morphological algorithm. Furthermore, the specific methods and processes to measure the walls crack with image digital processing were presented. And with the case study, it was found that this method can measure the cracks accurately with convenient operation.2485|1556|0更新时间：2023-11-28
- 摘要：A computeraided method for architectural shape design was developed based on the Lsystems algorithm, the shape grammar and the space surface equation theory. Various 3D entities such as building grounds, building walls and building domes with fractal characteristics could be generated in a short time by using the computer program. These generative 3D entities were saved in a component database which could help to accumulate design knowledge through continuous expansion. A building could successfully be formed by the designers through selecting proper building grounds, walls and domes from this database. The effectiveness of the proposed method was approved with a case study.1887|2362|1更新时间：2023-11-28
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