Details

Autor(en) / Beteiligte

• Ge, Zhenlong
• Sun, Qiang
• Geng, Jishi
• Zhang, He

Titel

Thermal effect on b-value of limestone subjected to uniaxial loading

Ist Teil von

• Arabian journal of geosciences, 2021-07, Vol.14 (13), Article 1282

Ort / Verlag

Cham: Springer International Publishing

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The mechanical properties of rock deteriorate at high temperatures, affecting the stability of the rock. Therefore, it is of great importance to predict the failure of rock at high temperatures. Through the uniaxial compression test, the acoustic emission (AE) characteristics of limestone during loading after being submitted to different heat treatment temperatures were studied, and the variation of the limestone b -value with temperature was discussed. The results show that the characteristics of AE during loading corresponds to the failure and deformation process of limestone. At the initial stage of loading, the AE count is small, and the b -value shows an upward trend. The b -value fluctuates at a certain level with the increase of stress. Near the yield strength, the AE count begins to show higher peaks, the accumulated AE curve appears as an obvious inflection point, and the b -value begins to decrease. Near the peak strength, the b -value further decreases. The variation in the b -value of limestone with temperature is closely related to the special thermal expansibility of calcite minerals. Lower than 700 °C, the calcite expands rapidly and the large-scale cracks in the limestone increase, causing the b -value to gradually decrease with temperature. Above 700 °C, the dolomite and calcite crystal decompose and the homogeneity of the rock increases, the b -value increases slowly.