cantilever/gravity walls
DESCRIPTION
Cantilever/Gravity Walls . Bar lists and estimates from standard design sheet . Cantilever/Gravity Walls. Cantilever walls have footings forward/back of the wall (wall is essentially a cantilevered structure Gravity walls have no footings . - PowerPoint PPT PresentationTRANSCRIPT
Cantilever/Gravity Walls Cantilever/Gravity Walls
Bar lists and estimates from standard design sheet
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Cantilever/Gravity WallsCantilever/Gravity WallsCantilever walls have footings
forward/back of the wall (wall is essentially a cantilevered structure
Gravity walls have no footings
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http://content.answers.com/main/content/img/McGrawHill/atchitecture/f0169-02.png
http://www.gravesconcrete.com/allaboutretainingwalls.htm
PrecastPrecast
3http://www.humes.com.au/ProdsServices/PrecastConcrete/PC_StorageWalls.shtml
Standard Design Sheets-Standard Design Sheets-CIP CIP Cantilever/Gravity Wall Standard
Note: Not to be used for design!!!! Handouts are old, rescinded standard sheets given solely for the educational purpose of looking at details and deriving bar lists.
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Some assumptions used for Some assumptions used for std. designstd. design Unit wt of earth – 120 pcf Unit wt of concrete – 150 pcf Active earth pressure of soil behind
wall – 30 psf (level surcharge) A one-ft depth of surcharge was
applied above the toe of the footing. Earth fill behind the wall was
assumed w/ the top of finished grade 0.75 feet below wall coping
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All retaining walls are All retaining walls are structures -----possible structures -----possible failure modesfailure modesOverturningSlidingEccentricity (footing can lift)Bearing pressure (footing can
burrow into the soil)Rotational stabilitySettling
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Retaining Wall FailuresRetaining Wall Failureshttp://www.youtube.com/watch?v
=EXjVXaqWDLo
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ExampleExampleGiven:Stem 8’Min. Allowable soil pressure=1
Ton/sq ftDesign friction coefficient= 0.5Wall is 40’ long
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ExampleExampleFrom Design Std:Footing width: 5’-2”Toe Projection: 1’-8”T Bars #5@18”H Bars #5@18”D Bars #5@18”B Bars #5@18”Concrete Unit Quantity: 0.88 cy/lf
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Drawing/Bar MarksDrawing/Bar MarksBar marks different than shown
on standard drawingsE indicates epoxy coated bars
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Cantilever Wall Bar List
Mark Size No Type Length (ft)Length
(in)Total
Length (ft) Wt/FTTotal
Weight (lb)
5WHFE 5 9 Straight 39 6 355.50 1.044 371
5WVFE 5 21 Straight 7 9 162.75 1.044 170
S-Bar 5WVR 5 28 Straight 7 9 217.00 1.044 227
5WHR 5 5 Straight 39 6 197.50 1.044 206
D-Bar 5WDR 5 28 Curved 5 4 149.33 1.044 156
5WFL 5 8 Straight 39 6 316.00 1.044 330
H-Bar 5WFTT 5 28 Straight 4 8 130.67 1.044 136
T-Bar 5WFTB 5 28 Straight 4 8 130.67 1.044 136
Data/Assumptions From Table Plain Rebar 1191 lbStem Height 8 ft Foot. Width 5'-2" Epoxy Rebar 541 lbSoil Pressure 1 T/sf Toe Proj. 1'-8" Conc Volume 35 cyCoef of friction 0.5 T-bars 5@18"Wall Length 40 ft H-bars 5@18" Total Price $8,626
D-Bars 5@18" Price/LF $216Conc Price $200 /cy S-Bars 5@18"Rebar $0.90 /lb Conc 0.88 cy/ftEpoxy rebar $0.95 /lb
Assume 3" End CoverAssume 3" cover on footingAssume 2" cover on stem