岩石的比重、孔隙率.doc

.3.2 岩石的比重、孔隙率a、岩石比重 岩石的比重就是指岩石的干比重除以岩石实体体积(不包括孔隙)，再与4时水的容重相比，即：式中，Gs岩石比重 Ws绝对干燥时体积为V的岩石重力(KN)Vs岩石实体(不包括孔隙)体积(m) w在4时水的容重，w10(KN/m)b、孔隙率岩石内孔隙体积与总体积(包括孔隙体积)之比，计算式为：根据岩石干容重d和比重Gs，也可以用下式计算：式中, n孔隙率,以百分数表示Vv孔隙、裂隙体积(m)V岩样总体积(m)图1.3.1b碳酸盐类岩石的抗压强度与孔隙率的关系。 图1.3.1b 描述岩体孔隙性的另一个指标，孔隙比。它是岩石孔隙体积与岩石实体体积之比，即:一些主要岩石的物理性质岩石名称比重密度 （g/cm）孔隙率 （%）吸水率 （%）岩 浆岩 花岗岩2.502.842.302.800.043.530.21.7花岗闪长岩2.652.651.51.81.51.8闪长岩2.603.102.522.960.253.00.180.40正长岩2.502.902.402.850.471.94辉长岩2.703.202.552.980.293.13流纹斑岩2.622.652.582.510.92.300.140.35流纹岩2.652.602.65粗面岩2.402.702.302.67安山岩2.402.802.302.751.092.19闪长玢岩2.662.842.492.782.15.10.41.0斑岩2.622.842.202.740.292.75玢岩2.602.902.402.86辉绿岩2.603.102.532.970.406.380.201.0玄武岩2.503.102.533.100.353.00.390.80橄榄岩2.903.402.903.40霏细岩2.662.842.622.781.592.230.180.35响岩2.402.702.402.70火山碎屑岩火山角砾岩2.503.002.202.90安山凝灰岩2.682.584.590.55粗面凝灰岩25.07凝灰质熔岩2.872.643.35沉积岩 硅质砾岩2.642.772.422.700.404.100.164.40石英砾岩2.672.712.600.349.3钙质胶结砾岩2.422.66粘土质胶结砾岩2.20石英砂岩2.642.772.422.771.049.300.144.10硅质胶结砂岩2.50泥质胶结砂岩2.602.702.202.605.0020.01.009.00页 岩2.572.772.302.467.59砂质钙质页岩2.472.602.007.002.306.00灰质页岩2.652.70致密石灰岩2.702.802.602.771.003.50.203.00白云质灰岩2.752.702.751.643.220.500.66泥质灰岩2.702.752.452.651.003.002.004.00变质岩 片麻岩(新鲜)2.692.822.652.790.702.200.100.70花岗片麻岩(强风化)2.302.50石英、角闪石片岩2.723.022.682.920.703.000.100.30云母、绿泥石片岩2.752.832.692.760.802.100.100.60硅质板岩2.742.812.712.750.303.800.70泥质板岩2.682.772.312.752.513.5千枚岩2.812.962.712.860.500.80石英岩2.702.7