Research on the development and application of dope-modified, environmentally friendly composite thin spray materials

The current underground roadway spraying materials face challenges such as low flexibility, poor adhesion, high rebound rate, easy cracking, and complicated construction procedures. In response to these issues, this study developed a new composite slurry material using white silicate cement (P·W) and fast-hardening sulfoaluminate cement (SAC) as base materials, with the addition of clay and fly ash as admixtures, along with xanthan gum, cellulose ether, naphthalene water reducing agent, and coagulant to enhance performance. The material’s properties and microstructure were evaluated through mechanical tests, setting time and flowability measurements, dry shrinkage tests, X-ray diffraction (XRD), and scanning electron microscopy (SEM), followed by field application to verify spraying effectiveness. The results demonstrated that the material possesses good flowability, adjustable setting time, rapid hardening, early strength, low dry shrinkage, and a large water contact angle. Field tests confirmed excellent flexible support performance, with the 100-mair leakage value reduced to 2.8 m 3 /min. Additionally, the material is environmentally friendly and promotes resource recycling. These findings provide a valuable reference for future slurry spraying construction and support the application of flexible support materials in underground engineering.