磷石膏/生土复合调湿材料研究

Study on phosphogypsum/raw soil composite humidity-controlling material

以磷石膏、生土为原材料,经无机掺合料改性,制备磷石膏/生土复合调湿材料。通过试验研究了材料的力学性能、耐水性及调湿性能。结果显示,将磷石膏掺量控制在5%~9%,复合调湿材料的60 d抗压强度为4.48~5.83 MPa;软化系数为0.71~0.82;最大吸湿速率达到0.0472~0.0516 kg/(kg·d);最大放湿速率达到0.0380~0.0434 kg/(kg·d)。微观分析显示,磷石膏本身具有胶凝作用,无机改性掺合料与原材料中的SiO_(2)反应,生成二水石膏、C-S-H凝胶、伊利石和钙沸石等物质,提高材料的强度和耐水性;复合调湿材料孔隙结构丰富,可通过毛细孔道效应、表面物理及化学吸附对水分子产生作用力,调湿性能优异。

With the effect of inorganic modified admixtures,phosphogypsum/raw soil composite humidity-controlling material was prepared by using phosphogypsum and raw soil as raw materials.The mechanical,water resistance and humidity-controlling properties of the humidity-controlling were explored through experiments.The results show that the composite content of phospho-gypsum is controlled at 5%~9%,the 60 d compressive strength of the material is 4.48~5.83 MPa.The softening coefficient is main-tained at 0.71~0.82.The maximum moisture absorption and desorption rates reach 0.0472~0.0516 kg/(kg·d)and 0.0380~0.0434 kg/(kg·d)respectively.The microscopic analysis shows that the hydration reaction of phosphogypsum and the reaction of inorganic modified admixture with SiO_(2)in raw materials produce dihydrate gypsum,C-S-H gel,Illite and Calcium Zeolite,which improves the strength and water resistance.The composite humidity-controlling material has rich pore structure,which can exert force on water molecules through capillary pore effect,surface physical and chemical adsorption,and has excellent humidity-controlling performance.