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Bridges & Structures

 

GEC 8 Tables

Table B.1. ASD Example Calculations for 18-inch Diameter - CFA pile in Cohesive Soils
    Side Shear Resistance End Bearing Resistance Total Resistance
A
Pile Embedment Depth		 B
Underdrained Shear Strength		 C
Alpha Factor		 D
Ultimate Unit Side Shear		 E
Ultimate Side Shear for Pile Segment		 F
Ultimate Side Shear		 G
Safety Factor		 H
Allowable Side Shear		 I
Average Undrained Shear Strength (2-Diam. Below Tip)		 J
Bearing Capacity Factor		 K
Ultimate Unit End Bearing		 L
Ultimate End Bearing		 M
Safety Factor		 N
Allowable End Bearing		 O
Ultimate Total		 P
Allowable Total
L
(ft)		 Su
(ksf)		 α fs
(ksf)		 ΔRs
(kips)		 Rs
(kips)		 SF
 		 RS(Allow)
(kips)		 Su(ave,2-D)
(ksf)		 Nc′ qp
(ksf)		 RB
(kips)		 SF RB(Allow)
(kips)		 RT
(kips)		 RT(Allow)
(kips)
Top Soil Layer (Medium Clay)10.600.550.331.560.02.00.00.605.073.046.42.02.75.42.7
20.600.550.331.560.02.00.00.605.573.345.92.03.05.93.0
30.600.550.331.560.02.00.00.606.083.656.42.03.26.43.2
40.600.550.331.560.02.00.00.606.593.957.02.03.57.03.5
50.600.550.331.560.02.00.00.606.844.107.32.03.67.33.6
60.600.550.331.560.02.00.00.606.844.107.32.03.67.33.6
70.600.550.331.560.82.00.40.606.844.107.32.03.68.04.0
80.600.550.331.562.32.01.20.606.844.107.32.03.69.64.8
90.600.550.331.563.92.01.90.606.844.107.32.03.611.15.6
100.600.550.331.565.42.02.70.606.844.107.32.03.612.76.3
110.600.550.331.567.02.03.50.606.844.107.32.03.614.37.1
120.600.550.331.568.62.04.30.606.844.107.32.03.615.87.9
130.600.550.331.5610.12.05.10.606.844.107.32.03.617.48.7
140.600.550.331.5611.72.05.80.606.844.107.32.03.618.99.5
150.600.550.331.5613.22.06.60.606.844.107.32.03.620.510.2
160.600.550.331.5614.82.07.40.606.844.107.32.03.622.011.0
170.600.550.331.5616.32.08.20.606.844.107.32.03.623.611.8
180.600.550.331.5617.92.08.90.606.844.107.32.03.625.112.6
190.600.550.331.5619.42.09.70.606.844.107.32.03.626.713.3
200.600.550.331.5621.02.010.50.606.844.107.32.03.628.214.1
210.600.550.331.5622.52.011.30.606.844.107.32.03.629.814.9
220.600.550.331.5624.12.012.10.606.844.107.32.03.631.415.7
230.600.550.331.5625.72.012.80.606.844.107.32.03.632.916.5
240.600.550.331.5627.22.013.60.606.844.107.32.03.634.517.2
250.600.550.331.5628.82.014.40.606.844.107.32.03.636.018.0
260.600.550.331.5630.32.015.20.606.844.107.32.03.637.618.8
270.600.550.331.5631.92.015.90.606.844.107.32.03.639.119.6
280.600.550.331.5633.42.016.70.606.844.1010.92.05.544.422.2
290.600.550.331.5635.02.017.50.606.844.1014.72.07.349.724.8
Bottom Soil Layer (Stiff to Very Stiff Clay)301.510.550.833.9136.52.018.31.538.3612.7922.62.011.359.129.6
311.530.550.843.9639.32.019.61.558.3712.9722.92.011.562.231.1
321.550.550.854.0143.22.021.61.578.3913.1623.32.011.666.533.2
331.570.550.864.0747.22.023.61.598.4013.3423.62.011.870.835.4
341.590.550.874.1251.22.025.61.618.4113.5323.92.012.075.237.6
351.610.550.884.1755.32.027.71.638.4313.7224.22.012.179.639.8
361.630.550.904.2259.52.029.71.658.4413.9024.62.012.384.042.0
371.650.550.914.2763.72.031.81.678.4514.0924.92.012.588.644.3
381.670.550.924.3267.92.034.01.698.4714.2825.22.012.693.246.6
391.690.550.934.3772.22.036.11.718.4814.4725.62.012.897.848.9
401.710.550.944.4276.62.038.31.738.4914.6625.92.013.0102.551.2
411.730.550.954.4781.02.040.51.758.5114.8526.22.013.1107.253.6
421.750.550.964.5285.42.042.71.768.5215.0426.62.013.3112.056.0
431.760.550.974.5789.92.044.91.788.5415.2326.92.013.5116.858.4
441.780.550.984.6294.42.047.21.808.5515.4227.32.013.6121.760.8
451.800.550.994.6899.02.049.51.828.5615.6127.62.013.8126.663.3
461.820.551.004.73103.72.051.81.848.5815.8127.92.014.0131.665.8
471.840.551.014.78108.42.054.21.868.5916.0028.32.014.1136.768.3
481.860.551.024.83113.12.056.61.888.6016.1928.62.014.3141.870.9
491.880.551.044.88117.92.059.01.908.6816.5129.22.014.6147.173.6
501.900.551.054.93122.82.061.41.928.6816.6929.52.014.7152.376.1
511.920.551.064.98127.72.063.91.948.6916.8629.82.014.9157.578.8
521.940.551.075.03132.72.066.31.968.6917.0430.12.015.1162.881.4
531.960.551.085.08137.72.068.81.988.6917.2130.42.015.2168.184.0
541.980.551.095.13142.72.071.42.008.6917.3930.72.015.4173.486.7
552.000.551.105.18147.82.073.92.028.7017.5631.02.015.5178.989.4
562.020.551.115.23153.02.076.52.048.7017.7431.32.015.7184.392.2
572.040.551.125.29158.22.079.12.068.7017.9131.72.015.8189.994.9
582.060.551.135.34163.52.081.72.088.7018.0932.02.016.0195.497.7
592.080.551.145.39168.82.084.42.108.7018.2632.32.016.1201.0100.5
602.100.551.155.44174.12.087.12.128.7118.4432.62.016.3206.7103.4
612.120.551.165.49179.52.089.82.148.7118.6132.92.016.4212.4106.2
622.140.551.185.54185.02.092.52.168.7118.7933.22.016.6218.2109.1
632.160.551.195.59190.52.095.32.188.7118.9733.52.016.8224.0112.0
642.180.551.205.64196.12.098.02.208.7219.1433.82.016.9229.9115.0
652.200.551.215.69201.72.0100.82.228.7219.3234.12.017.1235.8117.9
662.220.551.225.74207.42.0103.72.248.7219.5034.52.017.2241.8120.9
672.240.551.235.79213.12.0106.52.258.7219.6734.82.017.4247.8123.9
682.250.551.245.84218.92.0109.42.278.7319.8535.12.017.5253.9127.0
692.270.551.255.90224.72.0112.32.298.7320.0235.42.017.7260.1130.0
702.290.551.265.95230.52.0115.32.318.7320.2035.72.017.8266.2133.1
712.310.551.276.00236.52.0118.22.338.7320.3836.02.018.0272.5136.2
722.330.551.286.05242.42.0121.22.358.7420.5536.32.018.2278.8139.4
732.350.551.296.10248.52.0124.22.378.7420.7336.62.018.3285.1142.5
742.370.551.306.15254.52.0127.32.398.7420.9136.92.018.5291.5145.7
752.390.551.326.20260.72.0130.32.418.7421.0937.32.018.6297.9149.0
762.410.551.336.25266.82.0133.42.438.7521.2637.62.018.8304.4152.2
772.430.551.346.30273.12.0136.52.458.7521.4437.92.018.9310.9155.5
782.450.551.356.35279.32.0139.72.478.7521.6238.22.019.1317.5158.8
792.470.551.366.40285.72.0142.8Su needed 2-Diameters Below Tip
802.490.551.376.45292.02.0146.0
Table B.2. ASD Example Calculations for 18-inch Diameter CFA Pile in Cohesionless Soils
  SPT-N Values, Pile Depths and Segment Lengths Side Shear Resistance End Bearing Resistance Total Resistance
A
SPT-N Value		 B
Depth of Reported SPT-N Value		 C
Pile Embedment Depth (Bottom of Pile Segment)		 D
Depth of Mid-Point of Pile		 E
Length of Pile Segment		 F
Vertical Effective Stress at Mid-Point of Pile Segment		 G
Beta Factor		 H
Ultimate Unit Side Shear		 I
Ultimate Side Shear for Pile Segment		 J
Ultimate Side Shear		 K
Safety Factor		 L
Allowable Side Shear		 M
Average SPT-N Below Tip		 N O
Ultimate Unit End Bearing		 P
Ultimate End Bearing		 Q
Safety Factor		 R
Allowable End Bearing		 S
Ultimate Total		 T
Allowable Total
SPT-N
(blows / ft)		 L(SPT-N)
(ft)		 L
(ft)		 L(mid)
(ft)		 Δ L
(ft)		 σ′v
(psf)		 β fs
(tsf)		 ΔRs
(kips)		 Rs
(kips)		 SF RS(Allow)
(kips)		 N(ave) qp
(ksf)		 RS
(kips)		 SF RB(Allow)
(kips)		 RT
(kips)		 RT(Allow)
(kips)
Light Brown Fine Sand162.03.251.633.2501.200.000.00.02.50.021Intentionally Left Blank24.8043.82.517.543.817.5
274.55.754.502.5001.200.000.00.02.50.02328.0049.52.519.849.519.8
197.08.257.002.50581.200.070.80.72.50.32327.2048.12.519.248.819.5
249.510.759.502.502021.250.253.03.72.51.52428.4050.22.520.153.921.6
2512.013.2512.002.503461.170.404.88.52.53.42428.2049.82.519.958.323.3
2214.517.0015.133.755261.090.5710.118.62.57.42428.8050.92.520.469.527.8
2619.522.0019.505.007781.000.7818.437.02.514.81821.0037.12.514.874.129.6
Greenish-Grey Silty Fine Sand924.527.0024.505.0010560.550.5813.750.72.520.389.6017.02.56.867.727.1
729.532.0029.505.0013340.390.5312.463.12.525.289.0015.92.56.479.031.6
834.537.0034.505.0016120.420.6715.878.92.531.62630.6054.12.521.6133.053.2
Greyish-White Shelly Sand4339.542.0039.505.0019670.721.4133.3112.22.544.95464.20113.52.545.4225.790.3
6444.547.0044.505.0023230.661.5436.2148.52.559.46881.60144.22.557.7292.7117.1
7249.552.0049.505.0026780.611.6338.5186.92.574.87589.40158.02.563.2344.9138.0
7754.557.0054.505.0030340.561.7040.0226.92.590.87990.00159.02.563.6386.0154.4
8159.562.0059.505.0033890.511.7440.9267.92.5107.17990.00159.02.563.6426.9170.8
7664.567.0064.505.0037450.471.7541.2309.12.5123.67488.20155.92.562.3465.0186.0
7169.572.0069.505.0041000.421.7441.0350.12.5140.0SPT-N Values needed at least 2-Diameters Below Tip
Table B.3. ASD Example Calculations for 18-inch Diameter Drilled Displacement Pile in Cohesionless Soils
  SPT-N Values, Pile Depths and Segment Lengths Side Shear Resistance End Bearing Resistance Total Resistance
A
SPT-N Value		 B
Depth of Reported SPT-N Value		 C
Pile Embedment Depth (Bottom of Pile Segment)		 D
Depth of Mid-Point of Pile Segment		 E
Length of Pile Segment		 F
Vertical Effective Stress at Mid-Point of Pile Segment		 G
Unit Side Shear Constant		 H
Ultimate Unit Side Shear		 I
Ultimate Side Shear for Pile Segment		 J
Ultimate Side Shear		 K
Safety Factor		 L
Allowable Side Shear		 M
Average SPT-N Below Tip		 N
Unit End Bearing Constants		 O
Ultimate Unit End Bearing		 P
Ultimate End Bearing		 Q
Safety Factor		 R
Allowable End Bearing		 S
Ultimate Total		 T
Allowable Total
SPT-N
(blows / ft)		 L(SPT-N)
(ft)		 L
(ft)		 L(mid)
(ft)		 Δ L
(ft)		 σ′v
(psf)		 WS
(ksf)		 fs
(tsf)		 ΔRs
(kips)		 Rs
(kips)		 SF RS(Allow)
(kips)		 N(ave) WT
(ksf)		 qp
(ksf)		 RS
(kips)		 SF RB(Allow)
(kips)		 RT
(kips)		 RT(Allow)
(kips)
Light Brown Fine Sand162.03.25Not Needed for Drilled Displacement Piles3.25Not Needed for Drilled Displacement Piles0.001.6024.50.02.500.0SPT-N Values needed Approximately 4-Diameters Above Tip
274.55.752.500.002.7031.80.02.500.022084.36149.12.5059.6149.159.6
197.08.252.500.001.9022.420.12.508.123088.92157.12.5062.9177.370.9
249.510.752.500.002.4028.348.42.5019.423088.16155.82.5062.3204.281.7
2512.013.252.500.002.5029.577.92.5031.121080.56142.42.5056.9220.288.1
2214.517.003.750.002.2038.9116.72.5046.721077.90137.72.5055.1254.4101.8
2619.522.005.000.002.6061.3178.02.5071.216060.80107.42.5043.0285.5114.2
Greenish-Grey Silty Fine Sand924.527.005.000.000.9021.2199.22.5079.713047.5083.92.5033.6283.2113.3
729.532.005.000.000.7016.5215.72.5086.317063.65112.52.5045.0328.2131.3
834.537.005.000.000.8018.8234.62.5093.8310115.90204.82.5081.9439.4175.7
Greyish-White Shelly Sand4339.542.005.001.004.30101.3335.92.50134.44728178.00314.62.50125.8650.4260.2
6444.547.005.001.004.40103.7439.52.50175.86428178.00314.62.50125.8754.1301.6
7249.552.005.001.004.40103.7543.22.50217.37428178.00314.62.50125.8857.8343.1
7754.557.005.001.004.40103.7646.92.50258.87728178.00314.62.50125.8961.4384.6
8159.562.005.001.004.40103.7750.62.50300.27628178.00314.62.50125.81065.1426.0
7664.567.005.001.004.40103.7854.22.50341.7SPT-N Values needed Approximately 4-Diameters Below Tip
7169.572.005.001.004.40103.7957.92.50383.2

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