||This study uses the foaming agent to produce foam by the mortar mixer, and evenly mixes foam with Portland Cement and different weight ratios of aggregates (basic-oxygen-furnace slag replaces natural aggregates). In this experiment, foam concrete is mixed with different amounts of foaming agent and different substation rate of BOF slag. The purpose is to explore the properties of freshness, hardness, concrete durability, microstructure and cost analysis. The following is the mixture in this research: the amount of the addition of foaming agent, 0%, 0.2%, 0.5%, 0.8% and replacing the weight of natural aggregate, 0%、33%、67%、100% by BOF. There are 16 mixtures in total.|
The results show that: (1) The addition of foaming agent can effectively increase its workability. (2) Low replacement of BOF slag and use of foaming agent can reduce the concrete unit weight. (3) Appropriate replacement of BOF slag can effectively increase compression strength; the addition of foaming agent can improve the problem that compression strength of BOF slag decreases in 28 days. (4) The pores created by foaming agent enable BOF slag to swell inside the concrete; volumetric change is more stable if replacement of BOF slag is low, which can be testified by drying shrinkage. (5) The crystals produced in the soundness test break the concrete and cause weight loss, and the concrete with foaming agent can provide pores for crystals to form.