Papers by Author: Qing Zhang

Abstract: Buckling restrained brace is an economical tool for shock-absorbing. In this paper, it was used in a high-rise building. The shock-absorbing performance of the brace was analyzed under frequent earthquake condition with engineering software. It was found that with buckling restrained brace, the dynamic characteristics of the structure is changed, and the peak of the dynamic response is suppressed, making the storey drift of the structure meets the regulations.

Abstract: In order to analyze the effect of foundation pit excavation on surrounding buildings, this paper researched the ground surface deformation surrounding excavation engineering, analyzed the buildings additional internal forces change mechanism and the coordination of the building foundation and the ground; The damage were researched on foundation subsidence, ground tilt, surface curvature, torsion and other factors on surrounding buildings and affiliated facilities after excavation. Established an interaction theory model of the buildings foundation and ground, used the model could calculate the changes of internal force and deformation of surrounding buildings caused by foundation pit excavation by selecting the reasonable foundation settlement equation or using the measured settlement data. So this paper provided a theoretical calculation method to engineers to calculate the effect of excavation engineering on surrounding buildings.

Abstract: In this paper a skyscrapers frame-core wall structure as an example in Kun Ming, using two independent software, SATWE and ETABS, analyzed the dynamic characteristics and dynamic response of structures with earthquake in linear elastic phase and the elastic-plastic phase respectively, so that could evaluate rationality of the design of the structure as a whole and seismic performance superior or not, and it could provide an idea for audit drawing or proofread their own.

Abstract: In this paper a super high-rise frame-core wall as an example, It was analyzed the frame-core wall structure system under action of earthquake force features, set reasonable seismic performance objectives, analysis the structure reasonable failure mode, made it have enough bearing capacity and ductility for a reasonable design of frame and coupling wall-beam, could make the frame-core wall structure with multiple seismic fortification lines, improve the seismic performance of the frame-core wall structure. Finally, the action of earthquake deformation and seismic shear force distribution was analyzed through the elastic dynamic time-history analysis. After a reasonable optimization analysis showed: Frame-core wall structure could have three seismic fortification lines: coupling beams, core wall, frame structure, and had enough energy dissipation ability at the same time, could form the rational failure mode, improved the seismic performance of the structure.

Abstract: Activated cement with the characters of low water demand and high activity was made with Portland cement clinker and dehydrate-gypsum and liquid superplasticizer which were used as grinding additive in the grinding process. Three states of grinding effect exist with correspondence of different dosages of super-plasticizer: the optimal grinding aid dosage, the critical dosage, and the supercritical dosage. First, under the condition of the optimal grinding effect, the activated cement had the maximum strength with little dosage of super-plasticizer and small effect on the performance of activated cement; second, within the critical dosage, the strength of activated cement was similar to the common cement, more super-plasticizer were held and the performance of cement was obviously improved; third, within the supercritical dosage, the strength of activated cement was reduced, but it can accommodate much super-plasticizer, and had a remarkable influence on the performance of cement. The experiment also shows that different properties of low water demand activated cement can be made with admixture of different concentrations of super-plasticizer. Within the allowed limit, use more admixtures was in compile with green environmental protection concept, improve the durability of concrete, and resolve the problem of compatibility between common cement and super-plasticizer, and offered technical support in the produce of commercial concrete by directly use of Portland cement clinker.

Abstract: This paper analyzed natural vibration frequencies and vibration modes of suspend-dome structure with finite element method. Firstly, to get the corresponding vibration mode of each frequency of the structure, understand the distribution of directional stiffness in the structure, and realize the basic natural vibration characteristics, this paper analyzed the natural vibration characteristics of suspend-dome structure. And then, this paper analyzed such four parameters as rise, roofing mass, sectional stiffness of the rods, and prestress in the cables. Through comparison of the four parameters, we can get the similarities and differences among their frequencies and vibration modes, and whether or not the mass and the stiffness are harmonious, and draw some valuable conclusions for structural design.

Abstract: The paper presents a comparative study of particle size analyses of quicklime-stabilized dredged material (LSDM) by combined sieve-hydrometer method (SHM), laser diffraction method (LDM) and sieve method (SM). After analyzed the testing processes and compared the results comprehensively, some conclusions can be conduction. Adopting SHM and LDM to test the particle size of LSDM, not only break the structure unit of soil, but also change its property due to the pure water used as disperser. In addition, the severe flocculation, which attributed to the dissolvable salt in soil introduced by quicklime can’t be drainage effectively, result in the abnormal particle size distribution (PSD) curves produced by the SHM. Therefore, SHM and LDM are not suitable for the particle size analyses of LSDM. SM, without deteriorating the unit structure of aggregates and altering the properties of soil, should be adopted as the most suitable method for LSDM.

Abstract: As a new type of structural form, the suspend dome structure combines both advantages of the single layer reticulated shell structure and the cable dome structure. The anti-seismic performance of suspend dome have been analyzed by employing a computational model of the Kiewitt suspend dome with 40m span．The different seismic behaviors of time history analysis and response spectrum analysis are analyzed and compared. Some valuable conclusions are drawn for practical design. The results of anti-seismic analysis indicated that the components of the structure were in the elastic period，and had a good anti-seismic performance under 8 degree（0.2g）earthquake.

Abstract: In order to keep the river and harbor clear, the dredging activity need to be done continuously which has generated millions of cubic meters of dredged material (DM) every year in China. It is an economical and environment-friendly alternative of DM disposal to convert the dredged material to agricultural soil (CDMTAS) by adding admixture and/or dewatering. However, the corresponding evaluation criteria has not been reported so far to determine whether these treated DM are available for using as agricultural soils or not. 145 groups of data composed of weight and the shoes size of the adult was obtained by surveying in China, and a safety factor was given during the statistical analysis of the foot plantar pressure on the ground of adults, and 50 kPa is recommended for human agriculture activity loading on CDMTAS whose process could be regarded as undrained shear. Moreover, 16 kPa is recommended for the least undrained shear strength of CDMTAS that is required for bearing the human agriculture activity.