Inputs for Lpile Program
Round Pile Sections Diameter (in) 18 24 30 36 42 48
Moment of Inertia (in^4) 5153 16286 39761 82448 152745 260577
Modulus of Elasticity Concrete f'c (psi) 3,000 3,500 4,000 4,500 5,000
Area (in^2) 254 452 707 1018 1385 1810 Equation = 57,000*f'c^0.5 Modulus 3,122,019 3,372,165 3,604,997 3,823,676 4,030,509
Data-Boundary Conditions 1) Shear and Moment Use for Free Head Conditions, Pile wall as an example) 2)
Shear and Slope (Use for Fixed Head Conditions when slope = 0
3)
Shear and Rotational Stiffness May also be used for Fixed Head condition if a large rotational stiffness is applied Used for elastically-restrained pile-head connection
4)
Displacement and Moment Not commonly used in our work
5)
Displacement and Slope Retaining wall on top or toe of slope condition
Soil Type Since most of our work is with cohesive soil, use the silt Option (Phi-C Soil) The other parameters you will need are: Soil Parameters From Table 3.3 in Lpile Users Manual Clays Cohesion (C, Unconfined Consistency SPT Blow count, Ave Undrained Shear Strength lbs/ft^2) where Compression Max (N60, Max (Cu, lbs/ft^2) C= 0.5*qu Strength (qu, blows/ft) ref. lbs.ft^2) NAVFAC 7.01 Very Soft 250 260 2 520 Soft 4 500 520 1040 Medium 8 1000 1040 2090 Stiff 15 2000 2100 4180 Very Stiff 30 4000 4200 8350 Hard >30 8000 * 16700
Soil Modulus, K, Static (lbs/in^3)
30 100 500 1000 2000
Soil Modulus Strain, e 50 K, Cyclic ref. Table (lbs/in^3) 3.4 and 3.5 Lpile users * * 200 400 800
0.02 0.01 0.006 0.005 0.004
Sands
Very Loose Loose Medium Dense Very Dense
Max SPT (N'70) ref. Bowles, 1988 3 7 20 40 >40
Strain Value of strain at 50% of maximum stress, Value from Consol Curve Plate
Above WT
Submerg ed Not needed
25 90 225
20 60 125
