Experimental Study On Cracking Resistant Performance Of Prestressed Composite Basement Anti-Cracking Wall

The length of basement outer-walls of high-rise buildings is normally between 20 and 100 meters. Under the load action of temperature and shrinkage, the wallboard, bottom of which is strongly constrained by foundation, is easy to appear cracks. The structural function of basement outer-walls is to carry the upper loads of the structure, resist peripheral soil pressure and prevent groundwater penetrating into basement room. Once the basement outer-wall cracks, the structural performance of it will be impaired. Recent years, the problem of crack control about basement outer-wall has become more and more noticeable, but seldom got well solved. In this paper, a new method of crack control about basement outer-wall has been introduced. By using prestressed anti-cracking slabs, which are prefabricated beforehand, cast basement core-wall together with these slabs to compose the basement prestressed composite anti-cracking wall. The principle of the anti-cracking wall is to utilize the excellent cracking resistant performance of the prestressed anti-cracking slabs to reinforce the cracking resistant ability of the whole composite wallboard. This article is totally divided into five chapters, as follows:In the first chapter, briefly recited the main factors of the basement wallboard cracked and the generally measures of crack control, then raised the subject of this paper.In the second chapter, through axial extension test of model specimens, analyzed the cracking resistant performance of the basement anti-cracking wall. According to the different factors such as prestressed steel ratio, stretching control force and composite interfacial roughness, cast five groups model specimens, depicted the whole progresses of casting and experiment.In the third chapter, basing the experimental data, analyzed mechanical performance of each group model specimens, divided the failure progresses into four stages, compared the cracking resistant performance of each group.In the forth chapter, from the theoretic analysis, deduced the formulas of crack load, crack spacing and crack width of model specimens, compared the calculative results with the testing results, then summarized the measures how to enhance the crack resistant performance of the prestressed composite basement anti-cracking wall.In the fifth chapter, analyzed the whole wall-entity constrained by foundation, gained the constrained stress formulas under the temperature and shrinkage action, provided the design and construction methods of the prestressed composite basement anti-cracking wall.At the end of this article, summarized the whole paper, got the main concludes and pointed out the fields which need to further study.