甲:王技术员,石油沥青、煤沥青都是防水材料,从外观上看,两种沥青很难鉴别,你能告诉我怎么区分吗?乙:好啊!对这两种沥青用眼看是很难区分的。最简便的鉴别方法是锤击法。用锤轻击石油沥青,由于这种沥青韧性比较好,因而有弹性感觉,发出的声音发哑。煤沥青由于性脆, A: Wang technicians, petroleum bitumen and coal bitumen are all waterproof materials. From the appearance point of view, it is difficult to identify the two types of bitumen. Can you tell me how to distinguish between them? B: Well! Differentiated. The easiest way to identify is hammering. Tapping the bitumen with a hammer, due to the better toughness of this bitumen, it has a feeling of elasticity and sounds dumb. Because of the brittleness of coal tar pitch,