持续负温(-5℃)养护条件下含气混凝土性能劣化及孔结构发展规律试验研究OA北大核心CSTPCD

In this experiment,by comparing the compressive strength values and internal pore structure of five different aerated concrete test blocks at different ages under the conditions of negative temperature curing and standard curing,the development law of the compressive strength of aerated concrete is analyzed based on the(-5℃)curing condition,and the range of less harmful pores under this condition is further clarified based on the relationship between the pore size and the pore water;and the inherent lack of strength of aerated concrete is analyzed from a microscopic point of view.The experimental results show that the continuous(-5℃)curing has an obvious restraining effect on the growth of the compressive strength of aerated concrete,and the strength is less than the standard curing test block at the same content;under the same curing conditions,the strength and content are affected by the air-entraining agent.There is a negative correlation between them;based on the negative temperature curing environment,the high content of aerated concrete will reduce the compactness of the concrete due to the increase in the number of pores in the slurry,which will affect the compressive strength of the concrete to a certain extent,but it will cause the resistance of the aerosol to the negative temperature environment cannot be ignored.In order to analyze the balance between the negative temperature environment and the amount of air-entraining agent,the pore structure development law and strength growth system of cement-based materials under negative temperature are used to ensure that the compression the strength of aerated concrete is low and the pore structure is relatively optimized.Under the premise of finding the content of aerated concrete under the condition of negative temperature(-5℃).