Dynamic response of sandstones with different water contents based on SHPB
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摘要: 為研究不同含水狀態巖石力學性質的變化規律，并保證僅受含水量這一單一因素的影響，以砂巖作為試驗材料，制備飽和系數分別為2.82%、52.11%、100%的干燥、半飽和、飽和三種不同含水狀態的巖石試樣，進行靜載以及8種不同沖擊能量作用下的動力學性質的研究.通過試驗可知：在靜載作用下，相比干燥巖石，半飽和、飽和巖石試樣的應力-應變曲線隨含水量增加出現了峰值明顯降低的現象，抗壓強度分別降低了8.12%、19.26%.動載作用下，隨應變率的增加，3種巖石強度均呈現不同程度的線性變化，應力-應變曲線出現右移及峰值增加的現象，且干燥巖石與含水巖石在卸載階段有明顯不同的兩種趨勢，特別是在卸載第二階段.而在相同沖擊能量作用下，巖石的含水量越大，其破碎程度越大.Abstract: To study the changing law of rock mechanics under different water conditions and to ensure that the water content was the sole factor, sandstone was used as the experimental material. Three different kinds of rock samples were prepared with different moisture states whose average saturation coefficients were 2.82%, 52.11%, 100%, i. e., dry, semi-saturated, and saturated. The mechanical properties of the rocks were dynamically tested under the action of static load and eight kinds of impact energy. The experimental results reveal that under static load, compared with dry rock, the stress-strain curves of half-saturated and saturated rock samples show decreasing peaks with increasing water content, and their compressive strengths decrease by 8.12% and 19.26%, respectively. Under dynamic loading, with increases in strain rate, the strengths of the three samples show a linear change in different degrees, the stress-strain curves shift to the right, and the peak values increase. The dry and water-bearing rocks exhibit two obviously different trends in the unloading stage, especially in the second stage of unloading. Also, under the same impact energy, as the water content of the rock increases, the degree of fragmentation also increases.
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Key words:
- sandstones /
- water content state /
- dynamic response /
- sample preparation /
- stress-strain curve /
- peak stress /
- failure pattern
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參考文獻
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