For the last 10 years the authors performed a range of investigations aimed at furtherdevelopment of calculation methods and designing of walls of monolithic buildings. Investigationsincluded analytical study of stress and strain state of the walls in question at high levels of complexvertical and horizontal loading, studies being based on finite element method in nonlinear formulation.Under the above loading conditions there have been tested more than 100 sections of monolithicbuildings. Also there were carried out full-scale vibration-survival tests of multi-storeymonolithic buildings as well as shock-resistance dynamic tests up to destruction (using a specialpurposehigh-powered shaker unit) of two constructed for that very purpose 6-storey sections ofmonolithic buildings.On the data of the above theoretical and experimental investigations there was developed a newin its principle calculation model for the walls of such buildings [1], and reasoned formulationswere given with regard to their design fundamentals.Below there are stated the basic results of experimental study of strength, deformation andcrack-resistance of wall sections of monolithic buildings under combined loading with single-stageand multi-cycle alternating static loads.Intensive development of frameless construction of reinforced concrete (often high-rise) buildingsin various seismic regions of the world at the end of this century has outrun and anticipated theprogress of corresponding research-and-development activities.Consequently, on designing such buildings one had to adhere to general classic design philosophyregarding reinforced concrete structures, which, as we know, was based chiefly on the resultsof one-dimensional elements analysis. This entailed negative consequences of both technical andeconomic nature.Trying, as far as possible, to fill up the named gap in this particular scientific research niche theauthors carried out a comprehensive cycle of static tests of large-scale (half size) one-storey wallpanels shown in fig. 1.Analysis of results obtained in the course of these experiments proved that plane reinforcement(set along the whole surface of planes) definitely increased shearing resistance (Q-u ) of panels andwhat’s more, in such case there was evidence of linear dependence between Q-u and plane reinforcementcoefficient m. It is of no little significance as well, that plane reinforcement ensures“mild” damage pattern of the walls, their plasticity index lying in the range of 6.8-8.1. The most effectiveproved to be plane reinforcement by using diagonal frames.Differentiated estimation of plane reinforcement horizontal and vertical rods’ effectiveness allowedus to come to the conclusion that for panels with β=1 / h>1 (where “l” is the length and “h” isthe height of a panel) preference shall be given to vertical rods as being more effective.The best part of investigations was oriented towards revealing the pattern of contour verticalreinforcement behavior under loads. It is worth mentioning here that various investigators pass opposingopinions on the subject in question.Tests carried out by the authors as well as corresponding theoretical studies convincingly prove.
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