underdrain


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underdrain

[′ən·dər‚drān]
(civil engineering)
A subsurface drain with holes into which water flows when the water table reaches the drain level.

underdrain

underdrain
A drain, installed in porous fill, for drawing off surface water or water from the soil, as under the slab of a structure.
References in periodicals archive ?
0 for permeable interlocking concrete pavement (PICP) generates time-saving cross section drawings with base and subbase thicknesses, plus CAD drawings illustrating calculated hydrologic and structural requirements from user-designated rainfall events, runoff flows from contiguous surfaces, traffic loads, underdrains and soil subgrade characterizations.
The best option to improve subbase drainage and reduce the risk of premature pavement failure in an existing parking lot is to install an underdrain system to allow moisture a point of relief.
Following dewatering, the con tractor installed the geocomposite underdrain and established the subgrade for the liner system.
The underdrain pipes should be slotted with as many slots as possible, and slots should be as wide as possible.
In an installation with difficult influent characteristics, traveling bridge filters are installed with options that either "surface-wash" the upper layer of the media with jets of water or "air-scour" the full media bed with bubbles forced up through the underdrain along with the backwash water flow.
Tenders are invited for to provide quality adjustments, temporary traffic control devices, pavement removal, curb, concrete, remove sidewalk concrete, inlet removal, fence, chain & link removal & installation, concrete & concrete wall removal, pipe removal, excavation, subgrade treatment, structure backfill, concrete sidewalk & curb ramp, seeding & sodding, video inspection for pipe, aggregate for underdrains, geotextiles for underdrain, casting, water valve, adjust to grade, fire hydrant assembly relocation, water meter and line relocate, construction sign, temporary pavement marking, pedestrian signal head, conduit hdpe in.
Tenders are invited for work includes approx 8,600 cy unclassified excavation; 1,200 sy recycled concrete aggregate base course; 3,050 tn hma pavement; 1,000 sf pavement markings; 1,600 lf storm sewer; 4,050 lf underdrain.
Tenders are invited for this project will involve pavement removal, unclassified excavation, subbase course, recycled bituminous aggregate base course, pcc paving, underdrain installation, erosion control and seeding and mulching.
Topics include debris flow assessment and mitigation; rockfall rating systems; dam sinkhole evaluation; seismic imaging for landslide remediation; photogrammetry for mapping discontinuities, river morphology, and concrete damage; mine subsidence under levees; Laramie formation claystone behavior; underdrains for construction on expansive soils; reinforced soil structures; bedrock settlement under dams; energy foundations; and tunnel rehabilitation.
Tenders are invited for install subbase underdrains under the shoulders.
6,200 cy earth excavation; 295 lf pipe underdrains 4" (special); 9,126 ton coarse aggregate; 1,800 ton porous granular embankment, special; 925 ton stone riprap, class a4 (special); 2,400 sy geotechnical fabric.
Tenders are invited for hma surface removal, class d patching, placement of polymerized surface course, ada curb rampimprovements, hma shoulder repairs, grooved thermoplastic pavement markings, landscaping items, and other related items includes 1,338 lf 4" pipe underdrains type 1, 389 lf detector loop replacement.