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Bridging LayerFill
EmbankmentFill #2 Preload
Layer Thickness, H(ft) 3.5 4.5 0.0
Total Unit Weight, g(pcf) 135 115 110
Friction Angle, f(deg) 38 30 N/A
Young's Modulus, E(psf) 750,000 300,000 N/A
Poisson's Ratio, n 0.30 0.33 N/A
Pavement plus Traffic Surcharge Pressure, q (psf) 300
Time Available for Consolidation, t(days) 60
Allowable Post-Construction Settlement, SA (in.) 2.0
Depth to Groundwater, dw(ft) 3.0
Unit Weight of Groundwater, gw(pcf) 62.4
Exist Sand #1 Exist Sand #2 Clay #1 Clay #2
Layer Thickness, H(ft) 3.0 0.0 20.0 0.0
Total Unit Weight, g(pcf) 125 125 100 100
Young's Modulus, E(psf) 250,000 250,000 N/A N/A
Poisson's Ratio, n 0.33 0.30 0.35 0.35
Lat. Earth Press. Coeff., K0 0.50 0.50 0.60 0.60
Interface Frict. Angle btwn Soil and Column, d(deg) 32 32 24
24
Compression Ratio, Cec N/A N/A 0.220 0.220
Recompression Ratio, Cer N/A N/A 0.022 0.022
Coeff. of Consol., cv(ft2/day) N/A N/A
Initial Eff. Vert. Stress at Top of Layer, s'v,top (psf) N/A N/A
375 1127
Preconsol. Press. at Top of Layer, pp,top (psf) N/A N/A 375
1127
Initial Eff. Vert. Stress at Bottom of Layer, s'v,bot(psf) N/A
N/A 1127 1127
Preconsol. Press. At Bottom of Layer,pp,bot(psf) N/A N/A 1127
1127
Reduction in Required Bridging Layer Thickness, Hb,red(ft)
1.0
Geogrid Stiffness, J(lb/ft) 48,000
Long-term, In-Service, Allowable Geogrid Strength, S g(lb/ft)
2,000
Pile Cap Column
Vertical Distance from Top to Bottom of Element, H(ft) 0.0
23.0
Column Shape (use R for round and S for square) R R
Column Diameter or Width, dcor a (ft) 3.0 3.0Young's Modulus,
E(psf) 6,500,000 6,500,000
Poisson's Ratio, n 0.30 0.30
Center-to-center spacing, s (ft)
Value Criterion
Clear Spacing, s - a (ft) 4.3 5.7
Area Replacement Ratio at Ground Surface, a s 0.144 0.10
Bridging Layer Thickness, Hb (ft) 3.5 3.3
Maximum differential settlement of geogrid, d(in.) 6.4 N/A
Geosynthetic Strain, eg 0.039 0.05
Tension in the Geosynthetic Reinforcement, Tg(lb/ft) 1,872
2,000
Post-Construction Embankment Settlement, S (in.) 1.8 2.0
GeogridBridge1.0 analyzes column-supported embankments with
geosynthetic-reinforced bridging layers.
The complete report by Filz and Smith (2006), plus all
spreadsheet comments, should be read before using this
workbook.
Provide the input data in the cells with red text. The cells in
blue text are the calculated results based on the input data.
Definition sketches are provided in Figs. 1 through 5, which are
located to the right.
Project name, description, date, etc.
7.0
0.10
Guidance information for material property values is provided in
the pdf document to the right.
After providing all the proper input data, use the "Solve"
button located at Cell B62.
8/12/2019 GeogridBridge1.1
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Spreadsheet for calculating SRRnet and embankment settlement
without the preload.
Embank #1 Embank #2
thickness = 3.5 4.5 ft gam = 62.4 pcf Elev Area Pe
gam = 135 115 pcf dw = 3 ft (ft) (ft^2)
E = 750,000 300,000 psf ELw = -3 ft 0 7.07
nu = 0.30 0.33 0 7.07
phi = 38 30 deg 0 7.07
EL top = 3.5 8 ft -23 7.07
q = 300 psf Area of Unit Cell =
am H + q = 1290 psf
Exst Sand #1Exst Sand # Clay #1 Clay #2 J = 48,000 lb/ft
thickness = 3 0 20 0 ft
gam = 125 125 100 100 pcf
E = 250,000 250,000 -- -- psf
Cec = -- -- 0.22 0.22
Cer = -- -- 0.022 0.022
sig',v,top = 0 375 375 1127 psf
sig',v,bot = 375 375 1127 1127 psf
pp,top = -- -- 375 1127 psf
pp,bot = -- -- 1127 1127 psf
nu = 0.33 0.30 0.35 0.35
K0 = 0.50 0.50 0.60 0.60
delta = 32 32 24 24 deg
EL bot = -3 -3 -23 -23 ft
Groundwater
Geogrid
