含水粉煤灰泡沫混凝土力学性能退化试验研究

摘要

采用普通硅酸盐水泥、发泡剂、粉煤灰及外加剂制备采空区充填材料，通过室内试验研究不同含水率影响下充填体强度特性、蠕变特性、应力应变特性和变形特性退化规律。结果表明：自由水对充填体性能退化影响明显。具体表现为：随着含水率的增加，充填体抗压强度和抗剪强度递减，初期递减幅度较大，后期较小；充填体强度峰值、峰后残余强度及延性随着含水率增加而递减；随着含水率的增加，充填体弹性模量降低幅度较大，泊松比变化幅度较小，其他变形参数如剪切模量，体弹性模量均减小，充填体在水弱化情况下会进一步产生压缩，抗变形能力退化显著。%Ordinary portland cement, foaming agent, fly ash, admixture as raw material, make paste filling material. Study filling strength characteristic, creep properties,stress-strain relationship and deformation characteristic under the inlfuence of different moisture content by laboratory test. The results show that the weakening of the iflling is obvious in free water. Speciifc performance that with the increase of moisture content, the compressive strength and shear strength of filling decrease, early decrease range larger, latter smaller; peak strength of filling, post peak residual strength and ductility decrease with the increase of moisture content; moisture content increase, the elastic modulus decrease bigger, the Poisson’s ratio change smaller, other deformation parameters such as shear modulus, elastic modulus both decrease. The iflling further compressed in moisture content.