空隙百分率 meaning in English

percentage of voids

Methods of test for masonry units . part 3 : determination of net volume and percentage of voids of clay masonry units by hydrostatic weighing
圬工设施试验方法.第3部分:静流称重法测定粘土圬工设施中的空隙百分率和净容积
Methods of test for masonry units - part 9 : determination of volume and percentage of voids and net volume of calcium silicate masonry units by sand filling
圬工单位试验方法.第9部分:用沙充填法测定硅酸钙圬工单位的体积空隙百分率和净容积