翻译下面两段话(与土木工程有关)

A good sub-base, such as compacted aggregate material or fully compacted native soil (if structurally suitable) provides structural support of the path. If a path is constructed over a poor sub-grade, excavation to remove wet, organic or otherwise unsuitable material, treatment with soil-cement or application of a geotextile fabric may be required. Remove all organic material, including roots, when preparing the sub-grade. The application of a soil sterilant or lime at the sub-grade level may be required to control the growth of new vegetation. Paths built in wooded areas typically require special attention. Roots of trees and shrubs can pierce the surface of the path or cause it to heave and break apart. Preventive methods include removal of vegetation and realignment of the path away from trees. 收起