The embankment soil or foundation soil which is surrounded by the filter materials is called base materials. When the ratio of D15 of filter to D85 of base materials is less than 4 to 5, the base material is prevented from passing through the filters. Similarly,foundation when the ratio of D15 of filter materials to D85 of the base material is

The maximum limit of 0.3 mm on the surface width of cracks for concrete structures subject to mild exposure is acceptable. This limit of 0.3 mm is based basically on aesthetic considerations, but this limit is also considered to be satisfactory for the purpose of durability when the member is completely protected against weather or aggressive condi