Design of mix ratio of high toughness concrete for masonry reinforcement based on response surface method
In order to optimize the mix ratio of high toughness concrete for masonry reinforcement and study the influence of different factors and their interactions on the mechanical properties of high toughness concrete,response surface method was used to establish response models of equivalent bending toughness,equivalent bending strength,flexural strength and compressive strength by setting different levels of three factors:water-binder ratio,fly ash content and sand-binder ratio.The optimization results were verified by experiments.The results show that the water-binder ratio has a significant effect on the mechanical properties of high toughness concrete for masonry reinforcement,and it increases with the decrease of water-binder ratio.When the water-binder ratio decreases from 0.35 to 0.25,the peak bending load,failure deflection and equivalent bending toughness increases 100.0％,60.7％and 163.8％.The optimal mix ratio is 0.25 water-binder ratio,34％fly ash content and 0.31 sand-binder ratio.The bending load is 7.5 MPa,the failure defiection is 3.6 mm,the equivalent toughness is 380.3 kJ/m3.It shows the phenomenon of cracking and multiple cracks.The concrete has excellent strain hardening properties and toughness which is Class Ⅰ high toughness concrete.The test results are similar to those predicted by the model optimization,which indicates that the design test based on the response surface method has practical significance,and verifies the feasibility of the response surface method for the optimal design of the mix ratio of high toughness concrete for masonry reinforcement.
万方数据
维普
