The riverdeposit, which is made up of naturally graded sand and gravel, is characterized by its well gradation, easy control of its particle size, easy compaction and good permeability.
这种天然级配砂砾具有级配良好、粒径易控制、易碾压成型、透水性好等特点。
2
The Mississippi River, which used to sweep up dirt in one stretch of the delta only to deposit it in another, has now been channelled, for flood-prevention, to wash the land into the sea.