Sandstone and limestone are the main targets cut by oil and gas well drilling and for their physical mechanical property there have been systematic determination method and quantitative gradation.

砂岩和石灰岩是石油天然气钻井破岩的主要对象，它的物理力学性质已有系统的测定方法和定量分级。

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Vitrified microsphere; expanded perlite; insulating mortar; aggregate gradation; mechanical property; insulation property; workability;

玻化微珠； 膨胀珍珠岩； 保温砂浆； 骨料级配； 力学性能； 保温性能； 工作性；

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