Study On Shear Performance Of Beams Of A New Type Of Concrete

The early age cracking has been a serious problem for pumped concrete in the engineering application. And the big volume of cement mortar causes the high cost of pumped concrete. Scattering-filling aggregate technology can solve the above problems. Firstly, it can reduce the volume of cement mortar and the cost. Secondly, it can improve modulus of elasticity, volume stability and reduce the cracking of pumped concrete. Finally, it can improve the compressive strength, the splitting tensile strength and the flexural strength. So, the application of scattering-filling aggregate technology to pumped concrete has a high theoretical value and economic value.First, scattering-filling aggregate technology is applied to pumped concrete in order to study the performance of basic mechanics. Through testing on the C30, C40and C50 concrete with the volume replacement ratio ranging from 0% to 25%. With the increasing of volume replacement ratio, the compressive strength firstly increased and then decreased. And the compressive strength reached the maximum at 20% replacement ratio. The biggest increase of compressive strength (28d) reached 20.47% for C30,19.92% for C40 and 20.00% for C50. The slump loss decreased, but still exceeded 80mm, basically meeting the requirements of construction. The quantitative analysis is based on porosity, and the relatively accurate equation for strength calculation was got after regression. The quantitative analysis can be applied to ordinary concrete.Study on the shear performance of 13 scattering-filling aggregate beams and 3 standard beams, based on the performance of basic mechanics of scattering-filling aggregate pumped concrete. Through the tests, the effect of volume replacement ratio, strength grade of concrete, shear span ratio, stirrup ratio on the shear performance. With the increasing of volume replacement ratio, the ultimate shear firstly increased and then decreased. And the ultimate shear reached the maximum at 15% replacement ratio, the ultimate shear increased with the increasing of the strength grade of concrete, reduced with the increasing of shear span ratio and increased with the increasing of stirrup ratio. Study on the shear performance of beams can be useful to apply scattering-filling aggregate technology to true structural engineering.