Study On New Base Vibration Isolation And Anti-Seismic Technology Of Masonry Structure In Rural Areas

Rural buildings were severely damaged in Wen-chuan and Yu-shu earthquake. Toresearch and develop a new kind of anti-seismic structure and base-isolation structure forrural area has become a problem concerned by the engineering. Two kinds of anti-seismicstructure and one kind of base-isolation structure have been proposed and patented by theState Intellectual Property Office of China. In order to ascertain the seismic performance ofthe structures, the cyclic loading test study of the models constructed with the newanti-seismic technology has been carried out. The shaking table test study of the modelsconstructed with the new base-isolation technology has been carried out as well.Mechanical models and anti-seismic practical technology measures were proposed basedon the test. Main contributions are listed as follows:1. A new anti-seismic structure made of new style concrete block has been proposed.The low cyclic loading test study of2masonry walls with the new style concrete block and2normal masonry walls has been carried out. The load-bearing capacity, stiffness andstiffness degradation, ductility, energy dissipation capacity, and failure characteristics of themodels have been comparatively analyzed according to the test. The load-bearing capacityformula of the models has been established. One masonry structure model made of the newstyle heat preservation and load bearing block and one normal model have been tested onthe shaking table. The earthquake response has been analyzed and the dynamiccharacteristics deterioration law of the models has been given.2. A new anti-seismic structure made of recycled aggregate concrete (RAC) block wallwith constructional steel bars has been proposed. The experimental study of eight wallmodels with different design parameters has been carried out. The load-bearing capacity,stiffness and stiffness degradation, ductility, energy dissipation capacity, and failurecharacteristics of the models were comparatively analyzed according to the test. Theload-bearing capacity formula of the models was proposed in this paper. One masonrystructure model made of RAC blocks and constructional steel bars and one normal modelmade of RAC blocks have been tested on the shaking table. The dynamic characteristicsdeterioration law of the models has been revealed in this paper.3. A new kind of base-isolation masonry structure has been proposed in this paper. Thebase-isolation system includes a lower base beam, a top base beam, a compoundbase-isolation layer which is made of glass fiber cloth panels-graphite-glass fiber clothpanels, and inhibiting devices. One normal concrete block masonry structure with the new base-isolation system and one normal concrete block structure with the conventionalanti-seismic constructional measures have been tested on the shaking table. The models'earthquake response and the failure process have been comparatively analyzed based on thetest. The work mechanism of the base-isolation system has been revealed. Their mechanicalmodels have been proposed in this paper.4. The calculation model of the masonry structure made of new load-bearing concreteblock wall with constructional columns, the (RAC) brick masonry structure with verticalconstructional steel bars, and the new kind of base-isolation masonry structure have beenestablished. The nonlinear finite element was used to make the analysis. The anti-seismicmechanism and base-isolation mechanism have been revealed. The calculated results andexperiment results were in good agreement. And the practical anti-seismic andbase-isolation design methods and constructional measures have proposed as well.Main conclusions are as follows:(1) The proposed masonry structure made of new load-bearing concrete block wallwith constructional columns has the plump hysteretic curves and good seismicperformance.(2) The seismic performance of the RAC brick masonry structure with verticalconstructional steel bars is improved greatly.(3) The new kind of base-isolation masonry structure has better isolation performance.(4) The calculation models and the design methods of anti-seismic and base-isolationare simple and practical.