Cut-and-Fill Becomes Cut-and-Drain

by Christopher K. Coles, (A.M.ASCE), U.S. Navy Civil Engineer Corps.; FPO, San Francisco, CA,
Kange Shirata, (M.ASCE), Chf. Geotechnical Engr.; Ralph M. Parsons Co., Pasadena, CA,

Serial Information: Civil Engineering—ASCE, 1986, Vol. 56, Issue 12, Pg. 64-65

Document Type: Feature article


The U.S. Navy's facility in Subic Bay, Philippines, is in a mountainous area which experiences 182 inches of rain per year. These factors plus weak soil, made necessary an earth cut of 700,000 cu yd with numerous surface and subsurface drainage techniques. Subsurface techniques included trench drains on the slope with slotted pipe, gravel blankets, and filter fabrics; horizontal drains of 1½-in. and 6-in. slotted pipe; and peripheral trench drains to intercept percolating water above the slope. Surface drainage techniques included chevron drains, channels, and use of a local grass to prevent surface erosion under torrential rains. During excavation, earth to be used as fill was found to be well above optimum moisture content, which slowed compaction. This soil was double- or triple-handled for drying and to keep the excavation on schedule. Rock shore protection with filter fabric and matting was amended to the contract to protect the fill from wave action.

Subject Headings: Subsurface drainage | Rainfall | Trenches | Slopes | Filters | Fabrics | Excavation | Bays | Philippines | Asia

Services: Buy this book/Buy this article


Return to search