风积砂质胶凝材料充填性能及其在采空区治理中的应用

Filling Performance of Aeolian Sandy Cementitious Material and Its Application in Goaf Treatment

风积砂作为一种天然原料,用于空洞型采空区的充填可以很好地降低治理成本,具有显著的经济效益。为掌握风积砂质空洞型采空区充填材料的性能变化规律,研究了风积砂掺量对充填材料宏观性能及微观结构的影响规律。结果表明:随着风积砂掺量的增大,充填材料的黏度和稠度增大,且增长速率逐渐变大,导致充填材料输送性能变差;同时充填材料胶结体的抗压强度随风积砂掺量的增加呈先增大后减小趋势。当风积砂掺入量为40%时,充填材料中水化反应较为完全,水化产物可以较好地与风积砂界面结合,同时胶结体中孔隙分布均匀,抗压强度可以维持在较高水平;当风积砂掺入量超过或低于40%时,胶结体中水化产物较少,颗粒结合不紧密,存在大量孔隙,使抗压强度产生损失。使用风积砂掺量为40%的风积砂质充填材料,在陕北空洞型采空区治理中取得了良好的治理效果和经济效益。

As a natural raw material,aeolian sand can be used for filling hollow goafs,which can well reduce the cost of treatment and have significant economic benefits.For the purpose of grasp the performance variation law of aeolian sandy hollow goaf filling materials,the influence of aeolian sand content on the macroscopic properties and microstructure of filling materials was studied.The results show that with the increase of aeolian sand content,the viscosity and consistency of the filling material increase,and the growth rate gradually increases,resulting in the deterioration of the transport performance of the filling material.At the same time,the compressive strength of the cemented body of the filling material increased first and then decreased with the increase of aeolian sand content.When the incorporation amount of aeolian sand is 40%,the hydration reaction in the filling material is relatively complete,the hydration product can be well combined with the aeolian sand interface,and the pore distribution in the cement body is uniform,and the compressive strength can be maintained at a high level.When the amount of aeolian sand incorporation exceeds or falls below 40%,there are fewer hydration products in the cemented body,the particle bonding is not tight,and there are a host of pores,so that the compressive strength is lost.The use of aeolian sand-filled filling materials with a content of aeolian sand with a content of 40%has achieved good treatment effects and economic benefits in the treatment of hollow goafs in northern Shaanxi.