Experimental Study On Strengthening Method Of Low-grade External Pre-stressing Of Rural Masonry Structure

Masonry structure is widely used in housing constructions thanks to its significant advantages,such as low cost and simple construction.It's also one of the most widely used building structure form in our country's rural areas,however,this planted a safe hidden trouble,low strength and poor seismic performance for instance,at the same time.Some researches shows that in most rural regions of our country residence lack of necessary seismic construction measures,all previous earthquake in recent years,rural area earthquake damage shows that lack of necessary seismic construction measures of masonry buildings,the earthquake resistant ability is awful poor,once destructive earthquake is encountered,residents' personal and property safety,will face a serious threat.Structure reinforcement is a practical way to improve the seismic performance of masonry buildings,synthesis of various factors,this paper simplified the external prestressed strengthening method,to simplify the construction process and reduce the engineering cost,so as to better meet the requirements of rural houses reinforcement.First,the existing research shows that the one-way low-grade external pre-stress reinforcement can improve the seismic performance of masonry structure,on the basis of the research results,in order to better improve the reinforcement effect,this paper explored two-way low-grade externally pre-stressed reinforcement method,to improve the seismic performance of the wall between windows and connection performance of floorslab and wall,and made a contrast experiment with one-way reinforcement method.In order to meet the needs of the research,referring to the seismic atlas of rural residential building of Sichuan province,cancelled its structure measures,this paper designed a second model construction without ring beams and constructional column for my thesis.Second,the simulation shaking table experiment of unidirectional and bidirectional reinforced structure was carried out,conventional load and collapse simulation was implemented,at the same time,the experiment phenomenon and experiment data were analyzed.Experimental results show that: The seismic performance of structure reinforced with two-way reinforcement method are better than the one-way;Both two kinds of the reinforcement scheme can make the seismic performance of the structure obviously increased,meanwhile,the modal structure with two-way reinforcement can repeatedly bear more destructive earthquakes,after this grade of loading,the structure still maintain a certain carrying capacity,not collapsed;Both two methods can improve the interlayer displacement angle of structure limit(that is to improve the structure ductility),two-way reinforcement method have better improving effect;Two-way reinforcement can nice achieve the seismic fortification target of “repairable under moderate earthquake” and “no collapsing in the strong earthquake”;The existence of stress steel make structure show the characteristics of apparently severed but actually connected when it collapsed,nice prevented structural from comminuted collapse,simultaneously,it made the structure provide a certain amount of living space after the construction collapse.Finally,the article summarizes the destruction pattern of the structure similar to the experimental model in the actual earthquake damage,and compared the summarization with the experiment results,then drew the conclusion: The seismic performance of structure reinforced with pre-stressed reinforcement will improve on the basis of the original structure,make the structure can give a better play to its seismic potential.By comparison with actual earthquake damage and the experimental phenomena,it is concluded that two-way pre-stressed reinforcement method can make the structure give a greater degree to play its seismic potential,that is to say,the two-way pre-stressed reinforcement method which is simple executed and low cost,can effectively improve the seismic performance of masonry structure,and also can nice meet the requirements of reinforcement in rural areas.