The prediction of possible deformation in squeezing and swelling rocks in underground openings is presented. This article discusses the application and results of a urea-silica type chemical injection application to restrict the deformations in a U-shaped gallery opened in a rock mass having high swelling properties in an underground coal mine in the Eynez region, Soma (Turkey). The deformation problem before chemical injection, diligent application of a numerical model, prevention of deformation by chemical injections, and confirmation of this prevention by numerical model were examined and compared with field results. Numerical modeling study shows that high-deformations can be prevented. Rock borehole pressuremeter experiments were performed to determine the deformation modulus before and after chemical injections. The numerical model was analyzed and estimated using the results obtained from the in-situ experiments.