Research On Shear Behavior Of High Strength Stirrup And High Strength Concrete Beam

The latest issued "Code for design of concrete structures"(GB50010-2010) of our countryexplicitly eliminated HPB235low-level steel bar, promotion and use of high strength steel barsuch as the level of HRB400and HRB500. Research of HRB400above steel bar as stirrup hashad many research at home and abroad, and obtained certain achievements. However, themajority of test data is based on the combination of high strength steel bar and low levelconcrete, and have less test based on a combination of high strength steel bar and high strengthconcrete, the test data scattered and not fully, this paper collected43experiment data about thecombination of the high strength steel bar and high strength concrete at home and abroad, to sortand to analyze detailed for this type of shear damage experimental beams.Secondly, reference to the the related literature at home and abroad, put forward a newkind of shear-bearing capacity calculation model of the concrete softened strut-and-tie truss andarch-effects, deduction the Practical calculation formula of shear-bearing capacity, After thecollection of measured data of checking, the error compared to the calculated values andmeasured values is very small that probably forecast the shear-bearing capacity of thecombination of high strength stirrup and high strength concrete.In addition, under the action of concentrated load of shear bearing capacity calculationformula which in " Code for design of concrete structures"(GB50010-2010) for high strengthstirrup and high strength concrete composite reliability index of structures, use practicalengineering method-“first-order second moment method” to calculate and analysis. The resultsshow that the formula during code to the combination beams of high strength steel bar and highstrength concrete, reliability index is3.53, it’s only higher than the safety level three3.2ofbrittle failure in " Building structure reliability standard"(GB50068-2001),but still below thesafety level two and level one standards, reliability index is relatively low.Finally, using the finite element software ANSYS to analyze high strength stirrup and highstrength concrete composite beam which during the test, The analysis results show that, If thematerial model and constitutive relationship select reasonable, ANSYS could simulate thewhole process of shear failure of high strength stirrup and high strength concrete compositebeams.