Performance of mine cement grouting materials with ultra-fine cement at different water-cement ratios
ZHOU Bofang
MENG Xiangrui
WANG Yanfen
CHENG Xiang
ZHAO Guangming
LI Yingming
LIU Shaoze
Abstract：The water-cement ratio is a key factor affecting the performance of cement-based grouting materials.The hydration characteristics of multi-component cementitious systems at different water-cement ratios exhibit significant differences.To clarify the intrinsic relationship between the water-cement ratio and the performance of mine ultra-fine cement systems,ultra-fine cement-based grouting materials(UPCGM)were prepared by incorporating superplasticizers,expanding agents,and accelerators into ultra-fine silicate cement.Using various macro-and micro-testing methods,the effects of the water-cement ratio(0.45-0.80)on the performance of UPCGM slurry,mechanical properties,and microstructure of the hardened body were explored,and the underlying hydration mechanisms were analyzed in depth.The results indicated:①The water-cement ratio was positively correlated with the slurry flowability and setting time of UPCGM,while it was negatively correlated with the volume expansion rate of the hardened body.②As the water-cement ratio increased,the mechanical strength of UPCGM initially increased and then decreased.At a water-cement ratio of 0.50,the hardened body exhibited the best mechanical performance,with a compressive strength of 33.70 MPa at 3 days,an increase of 298.82%to 466.39%compared to water-cement ratios of 0.60 to 0.80.The 28 days compressive strength(50.70 MPa)and flexural strength(8.50 MPa)increased by 18.18%to 85.71%and 50.44%to 95.85%,respectively.③Thermodynamic modeling,XRD,FTIR,and SEM confirmed that changes in the water-cement ratio affected the hydration degree,hydration products,pore structure,and compactness of UPCGM,with the content and size of AFt increasing as the water-cement ratio increased.④Compared with the mine inorganic reinforced composite mortar(KWJG-1),UPCGM showed slightly lower flowability,early compressive strength,and flexural strength,but had significantly enhanced slurry stability,early setting properties,and later compressive strength.At water-cement ratios of 0.50 and 0.80,the 28 days compressive strength was 14.50%and 35.48%higher than that of KWJG-1,respectively,indicating potential applications in the field of roadway surrounding rock grouting reinforcement.
Keywords：ultra-fine cementwater-cement ratiogrouting materialscompressive strengthhydration mechanism
Publication Date：2025-08-31
Online Publishing Date：2025-09-05(First online date of this platform, not the publication date of the document)
Pages：16( 120-135 )