- For the section covering normal, natural background horizontal slope <20% organic dredging 30cm thick (up passages through swampy spot, standing water or mud, it suits all pockets encounter mud surface) before proceeding Executive embankment. When natural background horizontal slope of ≥ 20% to dig stairs, width 1m ≥ grade before embankment.
đang được dịch, vui lòng đợi..
