Advanced Materials Research Vols. 671-674

Abstract: According to the current seismic code, we model one project in PKPM, analysis the seismic resistance of the masonry structure with rigidity and flexibility floor, and study the earthquake shear and seismic capacity compared before and after such structural load changes and retrofitting. And the analysis conclusion can provide the reference of seismic design of such structures.

Abstract: Abstract: Based on the experimental investigation of quasi-static test of 5 AAC block walls and 1 clay brick wall, the hysteretic behaviors were analyzed on the basis of the experiments. The collapse resistant capacity of walls which were used two different materials was compared. It was shown that the seismic and collapse resistant capacity of autoclaved aerated concrete was improved obviously and reached the level of clay brick wall basically, which was added constructional middle column.

Abstract: For particular change of function, factories are sometimes to be retrofitted into specific buildings with insertion of additional floors. Conventionally, there are two methods in retrofit of factories when additional floor is needed. One is the reconstruction of a secondary structure inside the existing building, while the other is the so called direct construction of additional floor. The latter is preferred on particular occasions due to the simplification of procedure. However, strengthening is still required in this case for the loads induced by extra floor may impose an adverse effect on existing strucutre. In this study, the rubber isolation is introduced into retrofit of factories. Based on case study, its effect in isolating earthquake is evaluated, and relative discussion is also made with energy balance concept. The design procedure of retrofit design of factories with additional floors is discussed in this study, which may provide instruction in applying this technology into engineering practice.

Abstract: Short-leg shear wall is a new type of structure form, which is widely used and developed in our country for its reasonable architectural function, mechanical performance and engineering cost. The work further investigates the seismic performance of three kinds of short-leg shear wall. Classified and brief comments about the seismic performance and the exist drawback of the three kinds of shear wall and its application are conducted. Lastly, some useful suggestions and a new structure: Steel reinforced concrete short-leg shear wall with concealed bracing are proposed for the further research.

Abstract: The use of carbon reinforced polymer (CFRP) to provide lateral confinement for enhanced ductility and strength of reinforced concrete structures has been increasing. The present study, attempts to analytically investigate the effect of the layout of frame columns retrofitted with different layers of CFRP on the seismic performance and damage potential of structures under strong ground motion using realistic and efficient computational models. Based on the shaking table tests of several reinforced concrete (RC) flat slab beamless construction models, the seismic performance of structures strengthened with CFRP composites are investigated. The dynamic response of CFRP retrofitted structures and the components of the model, validation of the model, force-displacement relationship, relative displacement and the time history curves are studied. Then the rational effect of different CFRP layers is found.

Abstract: Combining with performance grades of reinforced concrete structures at home and abroad, the seismic performance of masonry-infilled frame structures can be induced into five levels: basically normal, slight damage, medium damage, severe damage and collapse prevention. The limit states of all seismic performance levels and their dominating parameters of masonry-infilled frame structures are put forward, and quantified performance index of this structure are obtained on the basis of statistical test data. The seismic response of pure and masonry-infilled frame structures are compared by using capacity spectrum method and equivalent strut model, and the result indicates that the structure could meet predetermined performance objective under the minor and major earthquake levels by comparing the practical story drift and proposed performance index.

Abstract: For the time being there are few literatures about study on the seismic performance of concrete hollow block masonry based on the finite element method, left fewer conclusions for reference. According to characteristics of the finite element software, which has strong capability of nonlinear analysis, some key problems are discussed, including the modeling of the concrete hollow block masonry structure, constitutive relations of the materials in block masonry, damage assessment, solution methods, the application of the dead and live loads and the earthquake wave and the seismic performance analysis. The time-history analysis is carried out on three different type walls with openings. Some key factors, such as core columns and ring beams, which have a great influence on the damage pattern and stability of the structure, are discussed. The conclusion from the paper can provide a beneficial reference for in-depth study of the seismic performance of concrete hollow block masonry and the damage patterns.

Abstract: So the consistent seismic wave model and multi-point seismic wave model are established based on the solid-fluid interaction theory in this paper. According to the analysis of the seismic response, the results show that: the effect on the dynamic response of the aqueduct in the soft site is greater when the seismic wave velocity is small. Therefore, in the seismic study of long-span structures, when the wave velocity is smaller, it is critical to consider the effect of the earthquake's multi-point input, so that the results can be coincident with the actual situation.

Abstract: In some accidents of earthquake, the steel frame was brittle damaged. The problem lied in the hinge part of the structure—beam-to-column connection. This made some academicians point out connection with haunch. In this article, the modal analysis and harmonic response analysis of frame are made at the basis of connection with haunch by using ANSYS. Through the model analysis, the natural frequency and relative vibration modes of the structure are gotten, which can help us prevent the frame from resonance, the harmonic response analysis is made based on the model analysis, the curve between the frequency and the deformation of each layer is drawn, from which we can also know the peak. The method used in the article can provide a train of thought about how to deal with complexly giant steel structure, and also lay the foundation for further research.

Abstract: Standing 250m above the ground level, the tower employs a complicated modern tall building system that involves the use of a reinforced core, two strengthened trusses and eight composite (concrete encased steel) mega-columns in the exterior perimeter of the building to resist vertical and lateral loads. A shaking table model test was carried out according to owner’s commission due to its complexity and the requirement of the Chinese Design Codes. In this paper, test equipments and test results were analyzed and some conclusions were given. The method applied in this model test will be helpful to other similar experimental studies.