Research On The Influence Of Waste Cooking Oil On Shrinkage And Durability Of High Shrinkage Concrete

Slag is a kind of green material which may replace cement in the future,but its application and development are limited by the shrinkage of alkali-activated concrete.Similarly,alkali-activated recycled concrete and low water-binder ratio concrete may affect the stability of the structure due to its high shrinkage.Some researchers have added traditional shrinkage reducing agent,expansion agent and emulsified edible oil to alkali-activated ordinary concrete,and compared their shrinkage effect,and found that emulsified edible oil has more ideal shrinkage effect.However,the optimum dosage of emulsified oil as shrinkage reducing agent and its influence on the shrinkage of alkali-activated recycled concrete and concrete with low water-binder ratio have not been studied.This topic will explore emulsified oil as shrinkage-reducing agent respectively to alkali-activated ordinary concrete,alkali-activated recycled concrete,low water-binder ratio shrinkage and durability of the concrete,the influence of mechanical properties,to find the right content,and through the MIP mercury injection test and SEM back scattering experiment analyzed the reasons of the change of macro,provide theoretical basis for the application of alkali excitation concrete,at the same time for domestic waste resource recycling of waste cooking oil to provide reliable path,promote the green development of concrete.The specific research work and conclusions are as follows:1)With the amount of emulsified oil(0,1%,2%)as the variable and the water-binder ratio of 0.5,the self-shrinkage,drying shrinkage,carbonation resistance,acid corrosion resistance,and compressive strength of 90 samples of alkali-activated ordinary concrete were studied.The reasons for emulsified oil to reduce the shrinkage of concrete 28 d,improve durability and reduce compressive strength were analyzed,and it was found that the 2% dosage is the optimal dosage for this water-binder ratio.2)Taking the amount of emulsified oil(0,2%)as a variable,the water-to-binder ratio is 0.5,and the cement-based recycled concrete as a comparison,self-shrinkage,drying shrinkage,carbonation resistance,acid corrosion resistance were carried out on 54 specimens of alkali-activated recycled concrete.Research on compressive strength,and analyze the reasons for the difference in shrinkage properties and durability between alkali-activated recycled concrete and alkali-activated ordinary concrete.3)With emulsified oil content(0,1%,2%),gelled material(slag,cement)as a variable,water cement ratio of 0.35,180 specimens of low water-binder ratio concrete autogenous shrinkage,dry shrinkage,carbonation resistance,compressivestrength,resistance to acid erosion,it is concluded that 2% dosage is the best dosage of cement concrete,but 2% emulsified oil has failed to make slag concrete shrinks to the ideal value,future research can increase the content of emulsified oil.4)The MIP mercury intrusion test and SEM backscattering test were used to observe the pore index and microscopic appearance of the alkali-activated cleansing pulp,and analyzed the reason why the emulsified oil reduced the porosity of the cleaned pulp,and the emulsified oil had a greater influence on the 7d compressive strength of concrete the reason.