Development and application of ordinary portland sulphoaluminate cement composite thin spray material

There are many problems such as large spraying thickness, poor adhesion, high rebound rate and complex construction operation in underground roadway spraying materials. In view of the above problems, uses portland cement, sulfoaluminate cement, fly ash, clay as the base material, with xanthan gum, cellulose ether and other admixtures to develop a new type of composite environmental protection thin spraying material. X-ray diffraction, scanning electron microscopy, mechanical property testing, contact angle analysis and other means are used to compare the existing similar materials, and the properties of the materials are studied and the microscopic morphology of the material surface is observed. Through field application, the spraying effect of the materials on the coal rock cracks in roadway is verified. The results show that the new material has non-toxic, non-combustible properties, high tensile and flexural strength, and can be used for flexible support of roadway. The material has good crystalline phase structure, small internal cracks, dense structure and strong adhesion to coal rock mass. The material has strong hydrophobicity, and the contact angle with water can reach 154.74°, which can absorb trace coal dust and gas. The material spraying effect is good. The gas content in the same roadway 10 h after spraying is 21% of that without spraying, which can block the gas escape and increase the roadway support strength.