DESIGN CALCULATIONS TAHOMA TERRAI HEREBY CERTIFY THAT THIS PLAN, SPECIFICATIONS, OR REPORT WAS PREPARED BY
ME OR UNDER MY DIRECT SUPERVISION AND THAT I AM A DULY LICENSED
PROFESSIONAL ENGINEER UNDER THE LAWS OF THE STATE OF WASHINGTON.
________________________________________________ DATE: March 7, 2022______
ROBERT J. RACE, P.E. LICENSE NO. 26697
DESIGN CALCULATIONS
TAHOMA TERRA PHASE 2 –
DIVISIONS 7 & 8
YELM, WA
SUBMITTED BY:
Robert Race, P.E.
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W1 S_184.0_to_194.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 13.39ft (12.61ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 0.78ft LL2 Width: 20ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22041.1408 1
RESULTS (Static / Seismic)
FoS Sliding:2.61 / [2.78 ]FoS Overturning: 4.40 / [2.47 ]
Bearing 1,806 / [ 1,676 ]FoS Bearing:9.35 / [ 11.01 ]
Pullout 1.50 NG
Total Pullout 28,363 FoS Total Pullout 11.17
Total Pullout (S)0 FoS Total Pullout (S) 0.37
Top FoSot: 25.57 FoS Connection: 3.23
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
7.00 12 8 SG200 1280 [2975]77 [181]1280 [1983]24.86 [11.50]818 [818]15.90 [4.74]0.00 [0.46](?)100.00 [58.87]
6.00 10 8 SG200 1280 [2975]183 [181]1280 [1983]10.46 [8.16]893 [893]7.30 [3.67]2.10 [1.06](?)18.94 [12.06]
5.00 8 8 SG200 1280 [2975]295 [181]1280 [1983]6.51 [6.30]967 [967]4.92 [3.07]4.85 [2.99]9.54 [6.41]
4.00 6 8 SG200 1280 [2975]406 [181]1280 [1983]4.73 [5.12]1041 [1041]3.85 [2.69]7.59 [5.22]5.95 [4.12]
3.00 4 8 SG200 1280 [2975]518 [181]1280 [1983]3.71 [4.32]1116 [1116]3.23 [2.43]10.34 [7.61]4.13 [2.98]
2.00 2 8 SG200 1280 [2975]516 [181]1280 [1983]3.72 [4.33]1190 [1190]3.46 [2.60]15.93 [11.72]3.19 [2.36]
1.00 0.67 8 SG200 1280 [2975]347 [181]1280 [1983]5.53 [5.72]1240 [1240]5.36 [3.57]30.22 [19.68]2.80 [2.10]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22041.1408 2
REA Analysis 5.1.22041.1408 3
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
3 22.03 13.39 -10.95 0.78 -1.16 24.61 25.77 1.208
3 19.36 13.39 -13.63 0.78 -2.66 21.55 23.48 1.215
3 22.03 13.39 -16.31 0.78 -3.84 27.46 29.45 1.217
3 19.36 13.39 -8.27 0.78 0.16 18.88 19.97 1.219
3 16.68 13.39 -10.95 0.78 -1.46 16.56 18.41 1.227
3 24.71 13.39 -13.63 0.78 -2.45 31.39 32.59 1.231
2 22.03 13.39 -13.63 0.78 -3.15 27.87 29.05 1.239
3 19.36 13.39 -16.31 0.78 -4.59 24.39 26.36 1.240
4 16.68 13.39 -13.63 0.78 -2.49 16.75 19.46 1.244
4 19.36 13.39 -10.95 0.78 -0.73 18.93 20.83 1.247
REA Analysis 5.1.22041.1408 4
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W2 S_15.0_to_30.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 15.02ft (13.99ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 1.03ft LL2 Width: 30ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22041.1408 1
RESULTS (Static / Seismic)
FoS Sliding:2.98 / [3.14 ]FoS Overturning: 5.49 / [3.05 ]
Bearing 1,921 / [ 1,868 ]FoS Bearing:11.27 / [ 12.19 ]
Pullout 1.50
Total Pullout 43,419 FoS Total Pullout 13.50
Total Pullout (S)0 FoS Total Pullout (S) 0.32
Top FoSot: 7.81 FoS Connection: 2.68
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
7.00 12.67 10 SG200 1280 [2975]152 [228]1280 [1983]12.63 [7.82]843 [843]8.32 [3.32]2.41 [0.96](?)45.55 [25.60]
6.00 10.67 10 SG200 1280 [2975]237 [228]1280 [1983]8.10 [6.42]917 [917]5.81 [2.97]5.63 [2.86]12.85 [8.67]
5.00 8.67 10 SG200 1280 [2975]348 [228]1280 [1983]5.52 [5.21]992 [992]4.28 [2.60]8.37 [5.03]7.14 [5.12]
4.00 6.67 10 SG200 1280 [2975]459 [228]1280 [1983]4.18 [4.38]1066 [1066]3.48 [2.35]11.12 [7.38]5.06 [3.74]
3.00 4.67 10 SG200 1280 [2975]570 [228]1280 [1983]3.37 [3.78]1141 [1141]3.00 [2.17]13.86 [9.84]4.05 [3.04]
2.00 2.67 10 SG200 1280 [2975]681 [228]1280 [1983]2.82 [3.32]1215 [1215]2.68 [2.04]16.61 [12.37]3.46 [2.62]
1.00 0.67 10 SG200 1280 [2975]516 [228]1280 [1983]3.72 [4.06]1290 [1290]3.75 [2.64]29.72 [20.46]3.00 [2.29]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22041.1408 2
REA Analysis 5.1.22041.1408 3
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
4 24.49 15.02 -14.90 1.03 -1.82 26.66 28.78 1.255
4 21.49 15.02 -11.90 1.03 -0.50 20.66 22.70 1.255
3 27.50 15.02 -20.91 1.03 -5.25 37.58 39.77 1.256
2 21.49 15.02 -14.90 1.03 -3.80 26.46 27.75 1.256
4 21.49 15.02 -17.91 1.03 -3.85 23.90 26.85 1.262
3 30.50 15.02 -17.91 1.03 -3.61 42.30 43.67 1.263
4 27.50 15.02 -17.91 1.03 -3.11 33.69 35.85 1.265
1 21.49 15.02 -8.90 1.03 -1.45 24.84 24.95 1.272
3 24.49 15.02 -17.91 1.03 -3.97 30.05 32.19 1.276
2 24.49 15.02 -17.91 1.03 -5.21 33.81 35.15 1.276
REA Analysis 5.1.22041.1408 4
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W3 S_28.0_to_32.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 14.32ft (13.57ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 0.75ft LL2 Width: 50ft
Leveling Pad Depth: 0.50ft Dead Load:0psf
Slope Angle: 0.0 deg Dead Load Offset: 0.0ft
Slope Length: 0.0ft Dead Load Width: 0ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22041.1408 1
RESULTS (Static / Seismic)
FoS Sliding:3.56 / [3.83 ]FoS Overturning: 6.36 / [3.11 ]
Bearing 1,757 / [ 1,810 ]FoS Bearing:11.29 / [ 11.15 ]
Pullout 1.50
Total Pullout 34,187 FoS Total Pullout 11.74
Total Pullout (S)0 FoS Total Pullout (S) 0.34
Top FoSot: 7.83 FoS Connection: 2.78
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
7.00 12 9 SG200 1280 [2975]121 [208]1280 [1983]15.92 [9.07]843 [843]10.49 [3.85]1.64 [0.60](?)39.10 [22.63]
6.00 10.67 9 SG200 1280 [2975]173 [208]1280 [1983]11.11 [7.84]893 [893]7.75 [3.53]3.91 [1.77]20.44 [12.25]
5.00 8.67 9 SG200 1280 [2975]309 [208]1280 [1983]6.21 [5.80]967 [967]4.69 [2.83]6.15 [3.66]11.19 [6.99]
4.00 6.67 9 SG200 1280 [2975]420 [208]1280 [1983]4.57 [4.79]1041 [1041]3.72 [2.52]8.90 [5.92]7.51 [4.84]
3.00 4.67 9 SG200 1280 [2975]532 [208]1280 [1983]3.61 [4.08]1116 [1116]3.15 [2.30]11.64 [8.33]5.60 [3.69]
2.00 2.67 9 SG200 1280 [2975]643 [208]1280 [1983]2.99 [3.55]1190 [1190]2.78 [2.13]14.39 [10.82]4.46 [2.99]
1.00 0.67 9 SG200 1280 [2975]490 [208]1280 [1983]3.92 [4.33]1265 [1265]3.87 [2.76]26.34 [18.39]3.70 [2.52]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22041.1408 2
REA Analysis 5.1.22041.1408 3
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
4 20.57 14.32 -14.37 0.75 -2.34 21.54 24.02 1.221
1 20.57 14.32 -8.65 0.75 -1.98 24.63 24.79 1.221
3 23.44 14.32 -8.65 0.75 0.32 24.27 25.17 1.222
3 26.30 14.32 -17.24 0.75 -3.95 34.74 36.50 1.224
4 20.57 14.32 -17.24 0.75 -4.38 24.40 26.91 1.230
3 20.57 14.32 -11.51 0.75 -1.30 21.31 22.96 1.230
3 23.44 14.32 -14.37 0.75 -2.64 27.50 29.22 1.232
4 23.44 14.32 -17.24 0.75 -3.56 27.49 30.04 1.234
2 20.57 14.32 -8.65 0.75 -1.88 24.43 24.62 1.241
3 17.71 14.32 -14.37 0.75 -4.16 21.31 22.96 1.241
REA Analysis 5.1.22041.1408 4
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W4 S_1.0_to_6.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 12.50ft (11.68ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 0.82ft LL2 Width: 20ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22054.807 1
RESULTS (Static / Seismic)
FoS Sliding:2.78 / [2.97 ]FoS Overturning: 4.96 / [2.77 ]
Bearing 1,652 / [ 1,564 ]FoS Bearing:10.46 / [ 11.87 ]
Pullout 1.50 NG
Total Pullout 16,308 FoS Total Pullout 7.51
Total Pullout (S)0 FoS Total Pullout (S) 0.40
Top FoSot: 41.46 FoS Connection: 3.01
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
6.00 11.33 8 SG200 1280 [2975]45 [230]1280 [1983]42.26 [10.82]818 [818]27.02 [4.46]0.38 [0.06](?)100.00 [77.99]
5.00 10 8 SG200 1280 [2975]120 [230]1280 [1983]15.98 [8.51]868 [868]10.83 [3.72]2.36 [0.81](?)30.36 [18.54]
4.00 8 8 SG200 1280 [2975]245 [230]1280 [1983]7.82 [6.30]942 [942]5.76 [2.99]4.85 [2.49]12.11 [8.03]
3.00 6 8 SG200 1280 [2975]357 [230]1280 [1983]5.38 [5.12]1017 [1017]4.27 [2.63]7.59 [4.59]7.23 [5.00]
2.00 4 8 SG200 1280 [2975]469 [230]1280 [1983]4.10 [4.32]1091 [1091]3.49 [2.38]10.34 [6.89]4.72 [3.37]
1.00 2 8 SG200 1280 [2975]580 [230]1280 [1983]3.31 [3.73]1165 [1165]3.01 [2.19]13.08 [9.31]3.52 [2.59]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22054.807 2
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W5 S_1.0_to_4.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 12.08ft (11.45ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 0.63ft LL2 Width: 30ft
Leveling Pad Depth: 0.50ft Dead Load:0psf
Slope Angle: 0.0 deg Dead Load Offset: 0.0ft
Slope Length: 0.0ft Dead Load Width: 0ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22054.1119 1
RESULTS (Static / Seismic)
FoS Sliding:3.72 / [4.03 ]FoS Overturning: 6.94 / [3.35 ]
Bearing 1,477 / [ 1,527 ]FoS Bearing:12.06 / [ 11.81 ]
Pullout 1.50
Total Pullout 24,622 FoS Total Pullout 11.89
Total Pullout (S)0 FoS Total Pullout (S) 0.41
Top FoSot: 9.55 FoS Connection: 3.59
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
6.00 10 8 SG200 1280 [2975]128 [172]1280 [1983]14.97 [9.90]843 [843]9.86 [4.21]1.84 [0.79](?)40.46 [23.51]
5.00 8 8 SG200 1280 [2975]222 [172]1280 [1983]8.64 [7.58]917 [917]6.20 [3.50]4.85 [2.72]15.48 [9.45]
4.00 6 8 SG200 1280 [2975]334 [172]1280 [1983]5.75 [5.94]992 [992]4.46 [2.97]7.59 [4.98]8.98 [5.69]
3.00 4 8 SG200 1280 [2975]446 [172]1280 [1983]4.31 [4.89]1066 [1066]3.59 [2.63]10.34 [7.41]6.21 [4.04]
2.00 2 8 SG200 1280 [2975]457 [172]1280 [1983]4.20 [4.81]1141 [1141]3.75 [2.77]15.96 [11.51]4.71 [3.13]
1.00 0.67 8 SG200 1280 [2975]311 [172]1280 [1983]6.17 [6.25]1190 [1190]5.74 [3.75]30.26 [19.31]4.06 [2.73]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22054.1119 2
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W6 S_1.0_to_33.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 9.06ft (8.56ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 0.50ft LL2 Width: 49ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22041.1408 1
RESULTS (Static / Seismic)
FoS Sliding:3.11 / [3.38 ]FoS Overturning: 5.84 / [3.00 ]
Bearing 1,144 / [ 1,127 ]FoS Bearing:11.80 / [ 12.46 ]
Pullout 1.50 NG
Total Pullout 10,064 FoS Total Pullout 8.82
Total Pullout (S)0 FoS Total Pullout (S) 0.52
Top FoSot: 9.49 FoS Connection: 4.81
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
5.00 7.33 6 SG200 1280 [2975]77 [116]1280 [1983]24.79 [15.36]818 [818]15.85 [6.33]1.06 [0.42](?)47.30 [26.30]
4.00 6 6 SG200 1280 [2975]145 [116]1280 [1983]13.22 [11.40]868 [868]8.97 [4.99]3.18 [1.77]15.75 [10.26]
3.00 4 6 SG200 1280 [2975]277 [116]1280 [1983]6.92 [7.65]942 [942]5.10 [3.64]5.67 [3.98]7.55 [5.17]
2.00 2 6 SG200 1280 [2975]317 [116]1280 [1983]6.05 [6.99]1017 [1017]4.81 [3.58]10.51 [7.63]4.79 [3.39]
1.00 0.67 6 SG200 1280 [2975]228 [116]1280 [1983]8.43 [8.81]1066 [1066]7.02 [4.74]21.35 [14.00]3.82 [2.76]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22041.1408 2
REA Analysis 5.1.22041.1408 3
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
2 13.69 9.06 -8.38 0.50 -1.51 15.51 16.51 1.245
3 13.69 9.06 -6.57 0.50 -0.17 13.62 14.59 1.267
3 15.50 9.06 -8.38 0.50 -1.03 17.58 18.59 1.271
2 15.50 9.06 -10.19 0.50 -2.35 19.81 20.84 1.280
3 13.69 9.06 -12.01 0.50 -3.04 16.43 18.28 1.286
2 17.31 9.06 -12.01 0.50 -3.18 24.77 25.82 1.286
2 17.31 9.06 -10.19 0.50 -1.86 22.20 23.25 1.294
1 19.13 9.06 -4.76 0.50 0.19 24.29 24.30 1.300
3 11.88 9.06 -10.19 0.50 -2.29 12.87 14.68 1.306
3 13.69 9.06 -10.19 0.50 -1.76 14.58 16.41 1.311
REA Analysis 5.1.22041.1408 4
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W7 S_55.0_to_68.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 6.27ft (5.06ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 1.21ft LL2 Width: 20ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22041.1408 1
RESULTS (Static / Seismic)
FoS Sliding:2.91 / [3.19 ]FoS Overturning: 5.20 / [2.56 ]
Bearing 818 / [ 784 ]FoS Bearing:14.47 / [ 15.81 ]
Pullout 1.50 NG
Total Pullout 2,900 FoS Total Pullout 5.72
Total Pullout (S)0 FoS Total Pullout (S) 0.76
Top FoSot: 4.30 FoS Connection: 7.35
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
3.00 4 4 SG200 1280 [2975]145 [93]1280 [1983]13.28 [12.54]843 [843]8.75 [5.33]1.03 [0.63](?)17.98 [11.62]
2.00 2 4 SG200 1280 [2975]187 [93]1280 [1983]10.26 [10.74]917 [917]7.35 [4.97]5.11 [3.40]6.83 [4.61]
1.00 0.67 4 SG200 1280 [2975]151 [93]1280 [1983]12.75 [12.44]967 [967]9.64 [6.07]12.38 [7.58]4.61 [3.19]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22041.1408 2
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W8 S_112.0_to_116.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 12.26ft (10.39ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 1.87ft LL2 Width: 30ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 25.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth Toe Slope Angle: 16.10
Toe Slope Length: 42.32
Toe Slope Bench: 0.00
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22041.1408 1
RESULTS (Static / Seismic)
FoS Sliding:3.52 / [3.74 ]FoS Overturning: 7.21 / [3.76 ]
Bearing 1,504 / [ 1,521 ]FoS Bearing:15.26 / [ 15.31 ]
Pullout 1.50
Total Pullout 30,282 FoS Total Pullout 14.11
Total Pullout (S)0 FoS Total Pullout (S) 0.39
Top FoSot: 7.44 FoS Connection: 3.51
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
6.00 10 9 SG200 1280 [2975]144 [177]1280 [1983]13.36 [9.27]843 [843]8.80 [3.94]3.67 [1.64]37.79 [22.76]
5.00 8 9 SG200 1280 [2975]232 [177]1280 [1983]8.27 [7.30]917 [917]5.93 [3.38]7.07 [3.99]13.62 [9.22]
4.00 6 9 SG200 1280 [2975]344 [177]1280 [1983]5.58 [5.77]992 [992]4.33 [2.89]9.81 [6.43]8.05 [5.68]
3.00 4 9 SG200 1280 [2975]455 [177]1280 [1983]4.21 [4.77]1066 [1066]3.51 [2.56]12.56 [8.98]5.63 [4.09]
2.00 2 9 SG200 1280 [2975]465 [177]1280 [1983]4.13 [4.71]1141 [1141]3.68 [2.71]18.67 [13.42]4.31 [3.19]
1.00 0.67 9 SG200 1280 [2975]316 [177]1280 [1983]6.07 [6.12]1190 [1190]5.65 [3.67]34.76 [22.07]3.73 [2.79]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22041.1408 2
REA Analysis 5.1.22041.1408 3
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
4 20.33 12.26 -19.96 -3.89 -11.03 32.17 37.15 1.106
5 22.78 12.26 -24.86 -5.31 -15.76 43.40 49.55 1.107
4 20.33 12.26 -17.51 -3.18 -8.54 28.91 33.33 1.107
4 22.78 12.26 -29.77 -6.72 -21.24 51.91 59.25 1.108
5 22.78 12.26 -22.41 -4.60 -13.11 39.48 45.05 1.112
5 20.33 12.26 -24.86 -5.31 -14.13 33.99 40.74 1.117
5 20.33 12.26 -29.77 -6.72 -19.19 40.96 48.85 1.117
4 22.78 12.26 -15.06 -2.48 -7.52 34.11 37.35 1.117
4 22.78 12.26 -27.32 -6.01 -18.47 47.54 54.28 1.122
5 20.33 12.26 -22.41 -4.60 -11.68 30.79 36.99 1.123
REA Analysis 5.1.22041.1408 4
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W9 S_309.0_to_434.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.458
SOIL PARAMETERS φ coh γ
Reinforced Soil: 36 deg 20psf 120pcf
Retained Soil: 36 deg 20psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 12.31ft (10.30ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 2.01ft LL2 Width: 30ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth Toe Slope Angle: 26.20
Toe Slope Length: 39.33
Toe Slope Bench: 0.00
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.13 Pullout: 1.50 / 1.13
Overturning:2.00 / 1.50 Uncertainties: 1.50 / 1.13
Bearing:2.00 / 1.50 Connection: 1.50 / 1.13
Shear:1.50 / 1.13 Bending: 1.50 / 1.13
REA Analysis 5.1.22059.810 1
RESULTS (Static / Seismic)
FoS Sliding:12.10 / [14.05 ]FoS Overturning: 57.36 / [25.50 ]
Bearing 1,509 / [ 1,534 ]FoS Bearing:33.71 / [ 33.16 ]
Pullout 1.13
Total Pullout 122,082 FoS Total Pullout 66.60
Total Pullout (S)0 FoS Total Pullout (S) 0.47
Top FoSot: 10.16 FoS Connection: 5.45
ID Height Length Name Ta_tn [Ta_tns]Rc %TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
6.00 10 12 SG200 1043 [2424]100 66 [191]1043 [2155]23.72 [9.45]843 [1124]19.17 [4.93]34.59 [8.89]26.92 [18.42]
5.00 8 12 SG200 1043 [2424]100 158 [191]1043 [2155]9.87 [6.97]917 [1223]8.68 [3.95]29.84 [13.48]15.56 [10.83]
4.00 6 12 SG200 1043 [2424]100 250 [191]1043 [2155]6.26 [5.55]992 [1322]5.95 [3.41]31.79 [17.90]13.07 [8.83]
3.00 4 24 SG550 2361 [5488]100 341 [191]2361 [4878]10.37 [10.45]1241 [1654]5.45 [3.54]84.32 [53.69]24.86 [16.42]
2.00 2 24 SG550 2361 [5488]100 354 [191]2361 [4878]9.99 [10.22]1309 [1745]5.54 [3.66]105.63 [68.11]17.54 [12.90]
1.00 0.67 24 SG550 2361 [5488]100 243 [191]2361 [4878]14.56 [12.83]1354 [1806]8.36 [4.75]179.36 [99.43]15.21 [11.26]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22059.810 2
REA Analysis 5.1.22059.810 3
COMPOUND RESULTS
Compound stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and
exiting out through the face of the wall. For MSE walls, the resistance of the geogrid reinforcement is included in the
analysis and the shear resistance of the face units is included.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
3 25.33 12.31 1.31 4.00 0.45 45.36 41.37 1.682
2 20.40 12.31 1.31 4.00 -10.58 57.40 54.71 1.694
3 22.87 12.31 1.31 4.00 0.45 38.35 34.36 1.719
2 32.71 12.31 1.31 4.00 -16.60 135.20 132.42 1.737
2 22.87 12.31 1.31 4.00 -11.73 69.94 67.22 1.740
3 27.79 12.31 1.31 4.00 0.43 53.14 49.14 1.745
2 30.25 12.31 1.31 4.00 -15.36 116.62 113.84 1.749
2 35.18 12.31 1.31 4.00 -17.86 155.29 152.50 1.780
3 20.40 12.31 1.31 4.00 0.44 32.09 28.10 1.784
2 17.94 12.31 1.31 4.00 -9.46 46.37 43.71 1.795
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
11 35.18 12.31 -37.25 -16.32 -27.07 63.85 80.81 1.078
10 37.64 12.31 -37.25 -16.32 -30.08 77.18 93.78 1.078
9 40.10 12.31 -37.25 -16.32 -34.08 93.93 110.29 1.084
12 35.18 12.31 -37.25 -16.32 -24.35 56.98 74.42 1.090
8 40.10 12.31 -37.25 -16.32 -39.53 108.64 124.98 1.093
11 37.64 12.31 -37.25 -16.32 -26.71 68.38 85.35 1.094
7 42.56 12.31 -37.25 -16.32 -46.90 136.16 152.78 1.094
9 37.64 12.31 -37.25 -16.32 -34.24 88.07 104.44 1.095
10 37.64 12.31 -34.79 -15.11 -26.47 72.29 87.80 1.097
13 32.71 12.31 -37.25 -16.32 -22.54 47.54 65.53 1.097
REA Analysis 5.1.22059.810 4
GEOGRID REINFORCING
STRUCTURAL PROPERTIES: Stratagrid
GEOGRID PROPERTIES
Name Tult RFcr RFd RFid Ci Cd Alpha Ltds
SG200 3600 1.55 1.10 1.35 0.90 0.90 0.80 1564
SG550 8150 1.55 1.10 1.35 0.90 0.90 0.80 3541
CONNECTION STRENGTHS
Geogrid Slope 1 Intercept 1 Peak Break Slope 2 Intercept 2 Max Normal Rup Conn Conn Creep Tlot (%)Tlot
SG200 28.00 1135 -1 0.00 0 1575 False 1.55 110 3960
SG350 26.00 1180 -1 0.00 0 2625 False 1.55 110 5500
SG550 26.00 1435 -1 0.00 0 3675 False 1.55 110 8965
SG600 26.00 1435 -1 0.00 0 3675 False 1.55 110 10010
SHEAR STRENGTHS
Slope 36 deg
Intercept 439psf
REA Analysis 5.1.22059.810 5
CALCULATION RESULTS
OVERVIEW
REA Wall calculates stability assuming the wall is a rigid body. Forces and moments are calculated about
the base and the front toe of the wall. The base block width or bottom reinforcement length is used in the calculations.
The concrete units, granular fill over the blocks or reinforced zone soils are used as resisting forces.
EARTH PRESSURES
The method of analysis uses the Coulomb Earth Pressure equation (below) to calculate active earth
pressures. Wall friction is assumed to act at the back of the wall face. The component of earth pressure is assumed to
act perpendicular to the boundary surface. The effective delta angle is delta minus the wall batter at the back face
(assumed to be vertical). If the slope breaks within the failure zone, a trial wedge method of analysis is used.
INTERNAL EARTH PRESSURES
Effective internal Delta angle (2/3 phi)delta =24.0 deg
Coefficient of active earth pressure ka =0.194
Internal failure plane ρ = 56.0 deg
EXTERNAL EARTH PRESSURES
Effective external Delta angle delta =36.00 deg
Coefficient of active earth pressure ka =0.236
External failure plane ρ = 59.0 deg
where :
δ = friction angle between fill and wall (degrees)
β = angle of fill to the horizontal (degrees)
θ = angle of bck face of wall to the horizontal (degrees)
φ'f = effective angle of internal friction (degrees)
REA Analysis 5.1.22059.810 6
FORCES AND MOMENTS
REA Wall resolves all the geometry into simple geometric shapes to make checking easier. All x and y
coordinates are referenced to a zero point at the front toe. The wall image can be exported to CAD for a more
detailed output.
Loads for Overturning about the FRONT TOE of the structure
Name Force (V)Force (H)X-len Y-len Mo Mr
Face Blocks(W1)1296 --1.57 ----2039
Soil(W2)935 --1.74 ----1626
Soil(W3)32246 --13.09 ----421954
Soil(W4)988 --24.45 ----24146
LL(W7)1058 --14.75 ----15615
DL(W8)750 --13.67 ----10253
Pa_h --1865 --4.10 7655 --
Pq_h --103 --6.16 637 --
Sum (V, H)37273 1969 Sum Mom 8291 475631
W0: leveling pad W6: Rectangle zone in broken back
W1: facing units W7: Live load over the mass
W2: soil wedge behind the face W8: Dead load over the mass
W3: rectangular area in MSE area W9: Force Pa
W4: the wedge at the back of the mass W10: Surcharge load Paq
W5: slope area over the mass W11: Dead Load Surcharge Paqd
X-Len: is measured from the center of the base (+) Driving, (-) Resisting.
Pa_h: horizontal earth pressure Pa_v: vertical earth pressure
Pq_h: horizontal surcharge pressure Pq_v: vertical surcharge pressure
REA Analysis 5.1.22059.810 7
BASE SLIDING
Sliding at the base is checked at the soil-to-soil interface between the reinforced mass and the foundation
soil.
Forces resisting sliding = (SumVr- W0 - W1 - W7)
37,273 - 0 - 1,296 - 1,058 SumVr = 34,919ppf
Resisting force = SumVr x tan(32) + c x L + Base Shear Rf1 =23,830
where L is the base width
where Base Shear = N tan(40.0) * 0.8 870.05
Driving force is the horizontal component of Pah + Pqh+ Pdh Df = 1,969
Factor of Safety = Rf/Df FSsl =12.10
REA Analysis 5.1.22059.810 8
OVERTURNING ABOUT THE TOE
Overturning at the base is checked by assuming rotation about the front toe by the block mass, soil retained
on the blocks or within the reinforced zone. Allowable overturning can be defined by eccentricity (e/L) or by the ratio
of resisting moments divided by overturning moment (FSot).
Moments resisting overturning = Sum(M1 to M6) + MPav + MPqv Mr =475,631ft-lbs
Moments causing overturning = MPah + MPqh Mo =8,291ft-lbs
Factor of safety = Mr/Mo FSot =57.36 OK
REA Analysis 5.1.22059.810 9
ECCENTRICITY AND BEARING
Eccentricity is the calculation of the distance of the resultant away from the centroid of mass. In wall
ReinDesign the eccentricity is used to calculate an effective footing width, or in rigid structure, it is used to calculate
the pressure distribution below the base.
Calculation of Eccentricity
e = (SumMr + M7 + SumMo)/SumV
Mr = -51,457.98
Mo = 32,110.73
e = (-51,457.98 + -2,914.61 + 32,110.73) /37,273.48)e =-0.454
Because 'e' is negative (leaning into the embankment), it is ignored to get the maximum bearing at the face
of the wall.
Calculation of Bearing Pressures
Qult = c*Nc + q*Nq + 0.5*gamma*(B')*Ng
where:
Nc =35.49
Nq =23.18
Ng =30.21
c =50.00psf
q =241.20psf
B' =24.91ft
Calculate Ultimate Bearing, Qult Qult =50,873.85psf
Applied Bearing Pressures = (SumVert / B' + (2B + LP depth)/2 * LP depth *gamma)
sigma =1,508.96psf
Calculated Factors of Safety for Bearing Qult/sigma =33.71
REA Analysis 5.1.22059.810 10
TENSION CALCULATIONS
Tmax is the maximum tension in the reinforcing based on the earth pressure and surcharge loads applied.
In the NCMA design method, earth pressures are calculated using the Coulomb Earth pressure equation. Infinite
surcharge loads are applied as q x ka. In designs were there is a broken back slope, or the surcharge is not uniform
over the area, a tie-back wedge analysis method is used.
FS = (Tal * FS_tn) / Tmax
TABLE OF RESULTS
Elevation[ft]ka z sv Name[ft]Tult[ppf]Ta[ppf]Rc %Tmax[ppf]FS
10.00 0.194 1.65 3.31 SG200 3,600 1,043 100 66 23.72
8.00 0.194 4.31 2.00 SG200 3,600 1,043 100 158 9.87
6.00 0.194 6.31 2.00 SG200 3,600 1,043 100 250 6.26
4.00 0.194 8.31 2.00 SG550 8,150 2,361 100 341 10.37
2.00 0.194 10.14 1.67 SG550 8,150 2,361 100 354 9.99
0.67 0.194 11.48 1.00 SG550 8,150 2,361 100 243 14.56
REA Analysis 5.1.22059.810 11
PULLOUT CALCULATIONS
Pullout is the amount of resistance of the reinforcing has to a pullout failure based on the Tmax applied and
the depth of embedment (resistance). In an NCMA design the failure place is defined as the Coulomb failure plane
which varies with face batter, backslope angle, and surcharge loads applied. All failure planes begin at the tail. of the
facing units.
For AASHTO calculations, the live load surcharge is not included in the Tmax value for pullout.
Failure Plane Angle (ρ) = 56.0 Deg
NOTE: The pullout capacity is limited by the Ultimate Strength of the reinforcing layer, not the ultimate pullout
capacity calculated.
F* = 0.67 x tan(φ) = 0.67 x 0.73 = 0.49
Le = embedment length = Li - block depth - hi * Tan(90 - ρ)
La = Li - Le
sv = geogrid spacing
Rc = % coverage
α = scale effect correction
Pullout = 2 x Le x F* x sv x α x Rc
TABLE OF RESULTS
Elevation[ft]Normal[lbf]Ci % Coverage Tmax[ppf]Le[ft]La[ft]Pullout_[Pr][ppf]FS PO
10.00 1744.17 0.90 100 66 5.47 6.53 2281 34.59
8.00 3587.10 0.90 100 158 6.60 5.40 4691 29.60
6.00 5973.26 0.90 100 250 7.73 4.27 7812 31.25
4.00 21553.08 0.90 100 341 20.86 3.14 28187 82.54
2.00 27960.04 0.90 100 354 21.99 2.01 36565 103.17
0.67 32533.16 0.90 100 243 22.75 1.25 42546 174.97
REA Analysis 5.1.22059.810 12
CONNECTION CALCULATIONS
Connection is the amount of resistance of the reinforcing has to a pullout failure from the facing units based
on the Tmax applied and the normal load on the units. In an AASHTO LRFD design, creep on the connection may be
applied for frictional and mechanical connections. In NCMA or AASHTO 2002, a frictional failure is based on the
peak connection capacity divided by a factor of safety. For a rupture connection the capacity is the peak load divided
by a creep reduction factor and a factor of safety.
Frictional Connection
Peak Connection = N(ppf) tan(slope) + intercept
Rupture Connection
Connection Capacity = [N(ppf) tan(slope) + intercept] / RFcr
RFcr can be a value obtained from long-term testing or by default could be the creep reduction factor of the
geogrid reinforcing.
Tal_cn = Allowable connection capacity = Tult_cn / FScn
Rc = % coverage
FS = Tal_cn * FScn/Tmax
TABLE OF RESULTS
Elev[ft]Name[ft]Tmax[ppf]Ttotal[ppf]Rc %N[ppf]Avail_CN[ppf]FS cn FS cns
10.00 SG200 66 191 100 243 843 12.78 4.42
8.00 SG200 158 191 100 453 917 5.79 4.81
6.00 SG200 250 191 100 663 992 3.97 5.20
4.00 SG550 341 191 100 873 1241 3.63 6.51
2.00 SG550 354 191 100 1083 1309 3.69 6.86
0.67 SG550 243 191 100 1223 1354 5.57 7.10
REA Analysis 5.1.22059.810 13
SEISMIC CALCULATIONS
The loads considered under seismic loading are primarily inertial loadings. The wave passes the structure
putting the mass into motion and then the mass will try to continue in the direction of the initial wave. In the
calculations you see the one dynamic earth pressure from the wedge of the soil behind the reinforced mass, and then
all the other forces come from inertia calculations of the face put into motion and then trying to be held in place.
Design Acceleration A = 0.458
Displacment (d)d = 2.0in
Design Acceleration Coefficient Displacment
Kh_d = 0.74 A (A/d)^0.25 = kh(int) = 0.234
Design Acceleration Coefficient Displacment Based (empirically)
Kh_d = 0.74 A (A/d)^0.25 = kh(ext) = 0.234
Vertical Acceleration kv =0.000
SEISMIC THRUST
INTERNAL Kae
Kae Kae =0.350
D_Kae = Kae - Ka = (0.350 - 0.194)D_Kae =0.156
EXTERNAL Kae
Kae Kae =0.371
D_Kae = Kae - Ka = (0.371 - 0.000)D_Kae =0.134
Pae = 0.5*gamma*(H)^2*D_Kae Pae =1,222ppf
Pae_h/2 = Pae*cos(delta)/2 Pae_h/2 =494ppf
Pae_v/2 = Pae*sin(delta)/2 Pae_v/2 =359ppf
INERTIA FORCES OF THE STRUCTURE
Face (Pif) = (W1)*kh(ext) = 1,296 * 0.234 Pif =304ppf
Mass (Pir) = (W)*kh(ext) = 5,523 * 0.234 Pir =1,295ppf
Slope (Pis) = (W)*kh(ext) = 0 * 0.234 Pis =0ppf
Dead Load(Pidl) = (DL)*kh(ext) = 0 * 0.234 Pidl =0ppf
TABLE OF RESULTS FOR SEISMIC REACTIONS
Name Force (V)Force (H)X-len Y-len Mo Mr
REA Analysis 5.1.22059.810 14
TENSION CALCULATIONS, SEISMIC
Tmax is the maximum tension in the reinforcing based on the earth pressure and surcharge loads applied.
For walls with extensible reinforcing, the inertial force shall be distributed uniformly to the reinforcements on a load
per unit width of wall bases as follows:
Tmd = (Pi/n)
where:
Tmd = incremental dynamic inertia force at Layer i
Pi = internal inertia force due to the weight of backfill within the active zone,
KhWa = where Wa is the weight of teh active zone and Kh is calculated as specified
n = total number of reinforcement layers in the wall
The total load applied to the reinforcement on a load per unit of wall width basis is determined as follows:
Total = Tmax + Tmd
where:
Tmax = the static load applied to the reinforcements.
In seismic design the mass is designed to resist the static and dynamic components of the load determined
as:
Srs >= Tmax RF/ Rc
where the reinforcing must be able to resist the load at any time of it's design life. Design for static loads
require the strength of the reinforcement be reduced for creep and other degradation mechanisms.The dynamic load
is a transient load and does not cause strength loss due to creep. The dynamic component of load for seismic design
is:
Srt >= Tmd RFid RFd/ Rc
The strength required for Tmax requires reduction for creep (Rc), where the strength for Tmd does not include the
effects of creep.
Srs = ultimate reinforcement tensile resistance required to resist static load component (kip/ft)
Srt = ultimate reinforcement tensile resistance required to resist dynamic load component.
Rc = reinforcement coverage ratio
RF = combined strength reduction factor to account for potential long-term degradation due to
installation damage, creep, and chemical aging
RFid = strength reduction factor to account for installation damage to reinforcement
RFd = strength reduction factor to prevent rupture of reinforcement due to chemical and biological
degradation
The required ultimate tensile resistance of the geosynthetic reinforcement shall be determined as:
Tult = Srs + Srt
REA Analysis 5.1.22059.810 15
Table of Results, Seismic Tension
Elevation[ft]Name Ta[ppf]Tas[ppf]Coverage Ratio %Tmax[ppf]TSmax[ppf]FS Str FSs Str
10.00 SG200 1043 2155 100 66 191 15.81 32.68
8.00 SG200 1043 2155 100 158 191 6.58 13.60
6.00 SG200 1043 2155 100 250 191 4.17 8.62
4.00 SG550 2361 4878 100 341 191 6.91 14.29
2.00 SG550 2361 4878 100 354 191 6.66 13.76
0.67 SG550 2361 4878 100 243 191 9.71 20.06
REA Analysis 5.1.22059.810 16
PULLOUT CALCULATIONS, SEISMIC
Pullout is the amount of resistance of the reinforcing has to a pullout failure based on the Tmax applied and
the depth of embedment (resistance). In an NCMA design the failure place is defined as the Coulomb failure plane
which varies with face batter, backslope angle, and surcharge loads applied. All failure planes begin at the tail. of the
facing units.
Failure Plane Angle (ρ) = 56.0 Deg
NOTE: The pullout capacity is limited by the Ultimate Strength of the reinforcing layer, not the ultimate pullout
capacity calculated.
F* = 0.67 x tan(φ) = 0.67 x 0.73 = 0.49
Le = embedment length = Li - block depth - hi * Tan(90 - ρ)
La = Li - Le
sv = geogrid spacing
Rc = % coverage
α = scale effect correction
Pullout = 2 x Le x F* x sv x α x Rc
TABLE OF RESULTS
Elev[ft]Rc %Tmax[ppf]Ttotal[ppf]Le[ft]La[ft]TRpo[ppf]TRpos[ppf]FS PO FS SeisPO
10.00 100 66 0 5.47 6.53 2281 2281 34.59 17.29
8.00 100 157 0 6.60 5.40 4691 4691 29.84 14.92
6.00 100 246 0 7.73 4.27 7812 7812 31.79 15.89
4.00 100 334 0 20.86 3.14 28187 28187 84.32 42.16
2.00 100 346 0 21.99 2.01 36565 36565 105.63 52.81
0.67 100 237 0 22.75 1.25 42546 42546 179.36 89.68
REA Analysis 5.1.22059.810 17
CONNECTION CALCULATIONS, SEISMIC
Facing elements shall be designed to resist the seismic loads, i.e., Ttotal.
The required ultimate tensile resistance of the geosynthetic reinforcement at the connection is:
Tult = Srs + Srt
In REA software, friction resistance at the base block is an option to reduce the tension on the bottom layer
of reinforcement. Research has shown the tension in the bottom layer of reinforcement to be very low if not zero.
Base friction is used to reduce the tension in the bottom layer of reinforcing. The force in the bottom layer is
the tension from half way to the reinforcing layer above to the halfway to the foundation level below.
Base Friction = 870.05 / 1.50 bs = 580ppf
Amount utilized to reduce bottom tension = 0ppf
REA Analysis 5.1.22059.810 18
TABLE OF RESULTS, Seismic Connection
Elev[ft]Name[ft]Tmax[ppf]Ttotal[ppf]Rc %N[ppf]Avail_CN[ppf]FS cn FS cns
10.00 SG200 66 191 100 243 843 12.78 4.42
8.00 SG200 158 191 100 453 917 5.79 4.81
6.00 SG200 250 191 100 663 992 3.97 5.20
4.00 SG550 341 191 100 873 1241 3.63 6.51
2.00 SG550 354 191 100 1083 1309 3.69 6.86
0.67 SG550 243 191 100 1223 1354 5.57 7.10
REA Analysis 5.1.22059.810 19
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W10 S_88.0_to_95.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 10.43ft (9.31ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 1.12ft LL2 Width: 20ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22055.650 1
RESULTS (Static / Seismic)
FoS Sliding:3.04 / [3.29 ]FoS Overturning: 5.70 / [3.06 ]
Bearing 1,346 / [ 1,307 ]FoS Bearing:12.46 / [ 13.45 ]
Pullout 1.50 NG
Total Pullout 16,132 FoS Total Pullout 10.53
Total Pullout (S)0 FoS Total Pullout (S) 0.48
Top FoSot: 43.48 FoS Connection: 4.30
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
6.00 9.33 7 SG200 1280 [2975]42 [128]1280 [1983]45.68 [17.45]818 [818]29.20 [7.20]1.12 [0.28](?)100.00 [77.11]
5.00 8 7 SG200 1280 [2975]117 [128]1280 [1983]16.41 [12.12]868 [868]11.13 [5.30]2.95 [1.40](?)26.84 [16.75]
4.00 6 7 SG200 1280 [2975]242 [128]1280 [1983]7.93 [8.09]942 [942]5.84 [3.84]5.37 [3.49]10.76 [7.19]
3.00 4 7 SG200 1280 [2975]354 [128]1280 [1983]5.42 [6.25]1017 [1017]4.30 [3.21]8.11 [5.92]6.39 [4.45]
2.00 2 7 SG200 1280 [2975]381 [128]1280 [1983]5.04 [5.95]1091 [1091]4.30 [3.27]13.29 [9.88]4.47 [3.16]
1.00 0.67 7 SG200 1280 [2975]266 [128]1280 [1983]7.22 [7.68]1141 [1141]6.43 [4.41]25.82 [17.26]3.57 [2.59]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22055.650 2
REA Analysis 5.1.22055.650 3
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
2 17.57 10.43 -11.22 1.12 -1.77 21.07 22.07 1.309
3 17.57 10.43 -9.14 1.12 -0.28 18.68 19.66 1.331
3 15.48 10.43 -13.31 1.12 -2.87 18.00 19.85 1.347
3 19.65 10.43 -11.22 1.12 -1.17 23.65 24.67 1.350
3 17.57 10.43 -15.39 1.12 -3.66 22.57 24.45 1.357
3 15.48 10.43 -11.22 1.12 -1.42 15.96 17.78 1.359
3 15.48 10.43 -7.05 1.12 0.63 14.45 15.38 1.360
2 15.48 10.43 -9.14 1.12 -0.87 16.47 17.43 1.362
2 19.65 10.43 -13.31 1.12 -2.66 26.41 27.44 1.362
2 21.74 10.43 -15.39 1.12 -3.52 32.48 33.53 1.369
REA Analysis 5.1.22055.650 4
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W11 S_88.0_to_96.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 20.99ft (19.37ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 1.62ft LL2 Width: 20ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22055.650 1
RESULTS (Static / Seismic)
FoS Sliding:2.70 / [3.11 ]FoS Overturning: 5.26 / [2.93 ]
Bearing 2,726 / [ 2,659 ]FoS Bearing:10.43 / [ 11.22 ]
Pullout 1.50 NG
Total Pullout 111,020 FoS Total Pullout 17.31
Total Pullout (S)0 FoS Total Pullout (S) 0.23
Top FoSot: 21.95 FoS Connection: 2.12
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
11.00 19.33 13 SG200 1280 [2975]73 [284]1280 [1983]26.31 [8.34]818 [818]16.82 [3.44]0.00 [0.32](?)30.14 [17.96]
10.00 18 13 SG200 1280 [2975]142 [284]1280 [1983]13.50 [6.98]868 [868]9.15 [3.06]0.00 [0.72](?)16.91 [10.66]
9.00 16 13 SG200 1280 [2975]271 [284]1280 [1983]7.08 [5.38]942 [942]5.21 [2.55]2.85 [1.39](?)12.40 [7.97]
8.00 14 13 SG200 1280 [2975]381 [284]1280 [1983]5.04 [4.50]1017 [1017]4.00 [2.31]6.06 [3.46]9.90 [6.40]
7.00 12 13 SG200 1280 [2975]491 [284]1280 [1983]3.91 [3.87]1091 [1091]3.33 [2.13]8.86 [5.59]7.73 [5.09]
6.00 10 13 SG200 1280 [2975]601 [284]1280 [1983]3.19 [3.39]1165 [1165]2.91 [1.99]11.77 [7.96]5.30 [3.88]
5.00 8 13 SG200 1280 [2975]711 [284]1280 [1983]2.70 [3.02]1240 [1240]2.62 [1.89]14.74 [10.50]4.44 [3.30]
4.00 6 13 SG200 1280 [2975]821 [284]1280 [1983]2.34 [2.72]1314 [1314]2.40 [1.80]17.75 [13.15]3.81 [2.87]
3.00 4 13 SG200 1280 [2975]931 [284]1280 [1983]2.06 [2.48]1315 [1315]2.12 [1.64]20.79 [15.88]3.34 [2.54]
2.00 2 13 SG200 1280 [2975]863 [284]1280 [1983]2.22 [2.62]1315 [1315]2.29 [1.74]28.75 [21.56]2.97 [2.28]
1.00 0.67 13 SG200 1280 [2975]554 [284]1280 [1983]3.46 [3.59]1315 [1315]3.56 [2.38]52.09 [34.27]2.70 [2.08]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22055.650 2
REA Analysis 5.1.22055.650 3
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
1 29.30 20.99 -15.42 1.62 -3.77 36.03 36.33 1.195
5 29.30 20.99 -19.62 1.62 -2.56 30.01 33.12 1.205
2 29.30 20.99 -19.62 1.62 -6.06 38.83 39.60 1.215
4 29.30 20.99 -19.62 1.62 -3.56 32.54 34.83 1.216
2 33.50 20.99 -15.42 1.62 -1.86 38.83 39.60 1.216
5 33.50 20.99 -23.81 1.62 -4.34 38.49 41.69 1.219
1 33.50 20.99 -23.81 1.62 -8.24 50.02 50.84 1.220
2 33.50 20.99 -23.81 1.62 -8.20 49.91 50.75 1.220
4 33.50 20.99 -19.62 1.62 -2.41 36.95 39.30 1.224
1 33.50 20.99 -19.62 1.62 -5.78 46.20 46.67 1.226
REA Analysis 5.1.22055.650 4
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W12 S_141.0_to_144.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 13.88ft (12.60ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 1.28ft LL2 Width: 20ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22055.650 1
RESULTS (Static / Seismic)
FoS Sliding:2.86 / [3.03 ]FoS Overturning: 5.15 / [2.87 ]
Bearing 1,811 / [ 1,734 ]FoS Bearing:11.26 / [ 12.49 ]
Pullout 1.50 NG
Total Pullout 36,235 FoS Total Pullout 13.21
Total Pullout (S)0 FoS Total Pullout (S) 0.36
Top FoSot: 14.72 FoS Connection: 3.14
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
7.00 12 9 SG200 1280 [2975]112 [195]1280 [1983]17.12 [9.69]843 [843]11.28 [4.12]1.43 [0.52](?)64.65 [37.82]
6.00 10 9 SG200 1280 [2975]211 [195]1280 [1983]9.11 [7.35]917 [917]6.53 [3.40]4.32 [2.24]16.69 [10.89]
5.00 8 9 SG200 1280 [2975]322 [195]1280 [1983]5.96 [5.80]992 [992]4.62 [2.90]7.07 [4.38]8.55 [5.85]
4.00 6 9 SG200 1280 [2975]433 [195]1280 [1983]4.43 [4.79]1066 [1066]3.69 [2.58]9.81 [6.73]5.43 [3.91]
3.00 4 9 SG200 1280 [2975]544 [195]1280 [1983]3.53 [4.08]1141 [1141]3.14 [2.35]12.56 [9.20]4.03 [2.98]
2.00 2 9 SG200 1280 [2975]539 [195]1280 [1983]3.56 [4.12]1215 [1215]3.38 [2.52]18.62 [13.60]3.29 [2.47]
1.00 0.67 9 SG200 1280 [2975]360 [195]1280 [1983]5.33 [5.44]1265 [1265]5.27 [3.47]34.70 [22.34]2.97 [2.25]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22055.650 2
REA Analysis 5.1.22055.650 3
GLOBAL RESULTS
Global stability is a global analysis (Bishop) with the failure planes originating at the top of the slope / wall and exiting
out below the wall in the area infront of the structure. For MSE walls, the resistance of the geogrid reinforcement is
included in the resisting forces. The curve may go through the base of the wall and the wall shear would be included.
In most cases the failure plane will pass below the structure.
ID Enter Point X Enter Point Y Exit Point X Exit Point Y Center X Center Y Radius FoS
3 25.55 13.88 -16.74 1.28 -3.14 32.91 34.43 1.272
3 22.77 13.88 -19.52 1.28 -4.81 29.19 31.54 1.284
4 20.00 13.88 -13.96 1.28 -1.76 20.45 22.72 1.293
4 22.77 13.88 -16.74 1.28 -2.87 26.05 28.39 1.294
3 22.77 13.88 -11.19 1.28 0.05 23.05 24.50 1.309
4 17.22 13.88 -11.19 1.28 -0.60 15.73 17.92 1.309
3 20.00 13.88 -11.19 1.28 -0.72 20.26 21.68 1.312
3 25.55 13.88 -13.96 1.28 -1.16 29.38 30.88 1.313
3 22.77 13.88 -13.96 1.28 -1.94 26.09 27.57 1.314
3 20.00 13.88 -16.74 1.28 -3.71 23.14 25.45 1.319
REA Analysis 5.1.22055.650 4
REA Analysis
Project:TAHOMA TERRA 7-8
Location:YELM, WA
Designer:rjr
Date:2/18/2022
Section: W13 S_604.0_to_606.0
Design Method: NCMA_09_3rd_Ed, Ignore Vert. Force
Design Unit: GravityStone Edge (CAN)
Seismic Acc: 0.400
SOIL PARAMETERS φ coh γ
Reinforced Soil: 32 deg 0psf 120pcf
Retained Soil: 32 deg 0psf 120pcf
Foundation Soil: 32 deg 50psf 120pcf
Leveling Pad: Crushed Stone
GEOMETRY
Design Height: 33.47ft (31.10ft Exp.)Live Load:50psf
Wall Batter/Tilt: 6.20/ 0.00 deg Live Load Offset: 2.00ft
Embedment: 2.37ft LL2 Width: 20ft
Leveling Pad Depth: 0.50ft Dead Load:250psf
Slope Angle: 0.0 deg Dead Load Offset: 10.0ft
Slope Length: 0.0ft Dead Load Width: 3ft
Slope Toe Offset: 0.0ft
Vertical δ on Single Depth Toe Slope Angle: 4.60
Toe Slope Length: 49.83
Toe Slope Bench: 0.00
FACTORS OF SAFETY (Static / Seismic)
Sliding:1.50 / 1.50 Pullout: 1.50 / 1.50
Overturning:2.00 / 2.00 Uncertainties: 1.50 / 1.50
Bearing:2.00 / 2.00 Connection: 1.50 / 1.50
Shear:1.50 / 1.50 Bending: 1.50 / 1.50
REA Analysis 5.1.22055.650 1
RESULTS (Static / Seismic)
FoS Sliding:2.99 / [3.41 ]FoS Overturning: 6.28 / [3.41 ]
Bearing 4,145 / [ 4,198 ]FoS Bearing:11.43 / [ 11.49 ]
Pullout 1.50
Total Pullout 496,856 FoS Total Pullout 30.62
Total Pullout (S)0 FoS Total Pullout (S) 0.15
Top FoSot: 48.36 FoS Connection: 1.55
ID Height Length Name Ta_tn [Ta_tns]TMax [Tmd]Tal/FS [seis]FS Tal [seis]PkCn [seis]PkCn/FS [seis]FS PO FS Sldg
17.00 32 22 SG200 1280 [2975]62 [467]1280 [1983]31.11 [5.63]818 [818]19.89 [2.32]3.86 [0.45](?)100.00 [71.50]
16.00 30.67 22 SG200 1280 [2975]134 [467]1280 [1983]14.35 [4.95]868 [868]9.73 [2.17]5.47 [1.22](?)53.33 [32.69]
15.00 28.67 22 SG200 1280 [2975]261 [467]1280 [1983]7.37 [4.10]942 [942]5.42 [1.95]7.58 [2.71]27.06 [17.51]
14.00 26.67 22 SG200 1280 [2975]370 [467]1280 [1983]5.19 [3.57]1017 [1017]4.12 [1.83]10.32 [4.55]7.20 [5.56]
13.00 24.67 22 SG200 1280 [2975]479 [467]1280 [1983]4.00 [3.16]1091 [1091]3.41 [1.74]13.07 [6.59]8.67 [6.42]
12.00 22.67 22 SG200 1280 [2975]589 [467]1280 [1983]3.26 [2.83]1165 [1165]2.97 [1.66]15.87 [8.81]9.37 [7.07]
11.00 20.67 22 SG200 1280 [2975]698 [467]1280 [1983]2.75 [2.57]1240 [1240]2.66 [1.61]19.13 [11.42]7.71 [5.90]
10.00 18.67 22 SG200 1280 [2975]807 [467]1280 [1983]2.38 [2.35]1314 [1314]2.44 [1.56]22.24 [14.04]6.55 [5.06]
9.00 16.67 22 SG200 1280 [2975]909 [467]1280 [1983]2.11 [2.18]1315 [1315]2.17 [1.44]?25.13 [16.54]5.69 [4.43]
8.00 14.67 22 SG200 1280 [2975]1033 [467]1280 [1983]1.86 [2.00]1315 [1315]1.91 [1.32]?27.35 [18.78]5.03 [3.95]
7.00 12.67 22 SG200 1280 [2975]1132 [467]1280 [1983]1.70 [1.88]1315 [1315]1.74 [1.24]?30.34 [21.41]4.52 [3.56]
6.00 10.67 22 SG200 1280 [2975]1257 [467]1280 [1983]1.53 [1.74]1315 [1315]1.57 [1.15]?32.57 [23.68]4.10 [3.25]
5.00 8.67 22 SG350 1777 [4132]1371 [467]1777 [2755]1.95 [2.27]1640 [1640]1.79 [1.35]?35.16 [26.16]3.93 [3.06]
4.00 6.67 22 SG350 1777 [4132]1480 [467]1777 [2755]1.80 [2.14]1640 [1640]1.66 [1.27]?37.86 [28.71]3.62 [2.83]
3.00 4.67 22 SG350 1777 [4132]1589 [467]1777 [2755]1.68 [2.03]1640 [1640]1.55 [1.21]?40.57 [31.28]3.35 [2.63]
2.00 2.67 22 SG350 1777 [4132]1408 [467]1777 [2755]1.89 [2.22]1640 [1640]1.75 [1.32]?52.23 [39.11]3.12 [2.46]
1.00 1.33 22 SG350 1777 [4132]1181 [467]1777 [2755]2.26 [2.53]1640 [1640]2.08 [1.50]67.65 [48.33]2.99 [2.36]
Column Descriptions:
Ta: allowable geogrid strength
Rc %: percent coverage for geosynthetics
EP (Pa) internal active earth pressure
LL (Pql) earth pressure due to live load surcharge
DL (Pqd) earth pressure due to dead load surcharge
Tmax maximum earth pressure on geosynthetic layer
FSstr factor of safety on geogrid strength (Ta/Tmax)
Ta cn allowable tension on the connection
FS Pkcn, factor of safety on the connection (Ta cn/Tmax)
FS PO, factor of safety on pullout (Ta pullout/(Tmax - LL)
Grid Embedment, depth of embedment beyond the theorectical failure plane.
REA Analysis 5.1.22055.650 2