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After the Tangshan earthquake, many of the national masonry structures were seismically strengthened, the vast majority of masonry constructions were strengthened with added ring-beams and tie-columns, in order to research this kind of masonry structure seismic performance, firstly the two-story masonry structure model is designed which didn’t taken any seismic measures, after building completed, the structure was strengthened couple with added ring-beams and tie-columns, researching content is as follows:1. In order to ensure the test material was up to specifications, during the period of model making, material mechanical performance was test, including the determination of the strength of the mortar, masonry compressive strength, shear strength, the compressive strength of concrete and reinforced the tensile test, etc.2. In order to obtain the dynamic characteristics of structure, the hammering method is adopted to reinforce the structure vibration characteristic test, included its frequency, vibration model and damping ratio, studying the structure of vibration mode under different damping ratio and natural frequency.3.The seismic response of acceleration, speed, restoring force and displacement of the strengthened masonry structure were obtained through the pseudo-dynamic test when rarely earthquake of Intensity7occurred; the reinforcement strain time-history curves of tie-columns root and beam-column junction were tested, then the restoring force-displacement curve of the structure was obtained after the pseudo-dynamic test. Then calculating the interlayer displacement Angle of structure, after the test, its stiffness degradation is not obvious, the structure is integral, with no destruction.4.By method of pseudo-static test, the strengthened masonry structure of the ultimate limit bearing capacity, limit deformation were obtained, the cracking part and developing process were observed. After the test, the parts of the wall destroyed of the masonry structure are mainly at the door or window openings and beam-column junction.Test shows that the strengthened masonry structure under rarely earthquake of Intensity7had good seismic performance, which can meet the current specifications of the seismic resistance.
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