| With the increasing global energy shortage,building energy conservation has drawn much attention in recent years.Some lightweight concrete has gradually become the focus of development and research.Foam concrete has drawn great attention and attention.However,the low strength is one of the most obvious shortcomings of foam concrete.In this paper,the effect of sisal fiber on the flexural strength of foam concrete is analyzed by studying the different amount of sisal fiber reinforced concrete.A total of 72 specimens,of which 18 were used as the static three-point bending test and 54 as the fatigue-bending test,were obtained by using non-standard trabecular specimens measuring 100 ㎜ × 100 ㎜ × 300 ㎜.With the purpose of anti-fatigue performance of sisal fiber foam concrete,the fatigue life of foam concrete with different sisal fiber content at three stress levels of 0.75,0.8,0.9 was studied.The main conclusion:(1)The flexural strength of foam concrete can be effectively improved by adding sisal fiber to foam concrete.With the increase of sisal fiber content,the flexural strength of foam concrete increases by 13%,20%,29%,14%,7%,when the sisal fiber content is 0.15%,it is relatively suitable dosage.(2)Through the bending fatigue test of sisal fiber reinforced concrete,it is found that there is a large dispersion of its fatigue life,which is extremely sensitive to the fatigue life of foam concrete,and the measurement system is closely related to the error,and draws its strain-Fatigue life curve,the destruction of sisal fiber foam concrete is a two-stage development.(3)The fatigue life is analyzed by Weibull distribution theory and lognormal distribution theory.It is found by regression analysis that there is a good linear relationship,which are in line with Weibull distribution and logarithm normal distribution.By contrast,Weibull distribution theory The logarithmic normal distribution theory is more suitable for fatigue life analysis of sisal fiber foam concrete.(4)On the basis of Weibull distribution,the fatigue life of foam concrete with different sisal fiber content under different failure probabilities was calculated.The double logarithmic fatigue equation was fitted,and its fatigue life could be obeying double pairs Number of fatigue equation distribution. |
