SPTfoundation.xlsx

	A	B	C	D	E	F
1	DETERMINISTIC SHALLOW FOUNDATION DESIGN USING SPT DATA
2	Version 1.0
3	developed by Dimitris P. Zeccos, available by the Geoengineer Website
4	Input values
5	N	10
6	ER	60
7	SPT Correction factors
8	Cs	1
9	Cr	1
10	Cb	1
11	Ce	1
12	N60	10
13	D/B	0.5
14	effective unit weight (kN/m^3)	9.23
15	Foundation Width (m)	1.2	1	1.5	2	3.048
16	Depth of interest (m)	1.2	1	1.5	2	3.048
17	Vertical effective stress (kPa)	11.076	9.23	13.845	18.46	28.13304
18	Liao&Witman depth correction factor	0.3328	0.3038	0.3721	0.4297	0.5304
19	N1,60	20.00	20.00	20.00	20.00	18.85
20	TERZAGHI BEARING CAPACITY EQUATION FOR SANDS
21	Applied Factor of Safety	3.00
22	Using Hatanaka & Uchida (1996), Mayne (2001) equation
23	Friction angle (degrees)	37.5	37.5	37.5	37.5	37.0
24	Ngamma (Chen)	94.4	94.4	94.4	94.4	86.5
25	Ngamma (Brinch-Hansen)	52.0	52.0	52.0	52.0	47.7
26	Nq (same for all)	46.1	46.1	46.1	46.1	43.1
27	Ultimate capacity (kPa)	543.4	452.9	679.3	905.7	1277.8
28	Allowable stress (kPa)	181.1	151.0	226.4	301.9	425.9
29	Using De Mello (1971), Schmertmann (1975) and Mayne (2001) equation
30	Friction angle (degrees)	41.4	41.7	41.1	40.5	39.4
31	Ngamma (Chen) (not used)	188.2	197.3	175.9	158.1	129.5
32	Ngamma (Brinch-Hansen)	102.6	107.5	96.0	86.5	71.1
33	Nq (same for all)	78.5	81.5	74.5	68.6	58.8
34	Ultimate capacity (kPa)	1003.3	872.0	1180.4	1431.5	1826.5
35	Allowable stress (kPa)	334.4	290.7	393.5	477.2	608.8
36	Using Empirical Meyerhof (1956) equation for bearing capacity
37	Ultimate capacity (kPa)	295.3	246.1	369.1	492.2	750.0
38	Allowable stress (kPa)	98.4	82.0	123.0	164.1	250.0
39	DEFORMATION CRITERION
40	Using Burland & Burbridge (1984) Approach
41	Allowable settlement (mm)	25.4
42	Inducing mean-σ stress (KPa)	180.9	205.5	154.7	126.5	94.2
43	Inducing mean stress (kPa)	329.2	374.0	281.6	230.2	171.4
44	Inducing mean+σ stress (KPa)	599.0	680.5	512.4	418.9	311.9
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68	Notes:
69	Methods developed according to correlations provided in the references. No responsibility is assumed for the results of the spreadsheet.
70	The values in the yellow boxes are those that the user can change.
71	Corrections for the blowcount according to Youd et al (2001)
72
73	References:
74	Burland, J.B., Burbidge, M.C. (1984), Settlement of foundations on sand and gravel, Proceedings of the Institution of Civil Engineers, Part 1, 1985, 78, Dec., 1325-1381.
75	Hatanaka, M., Uchida, A. (1996). Empirical correlation between penetration resistance and effective friction of sandy soil. Soils & Foundations, Vol. 36 (4), 1-9, Japanese Geotechnical Society.
76	Mayne, P.W. (2001), Geotechnical site characterization using Cone, piezocone, SPTu, and VST, Civil and Environmental Engineering Department, Georgia Institute of Technology
77	Meyerhof, G.G. (1956), Penetration tests and bearing capacity of cohesionless soils, Journal of the soil mechanics and foundation division, ASCE, Vol. 82, No. SM1, January, pp. 1-19.
78	Schmertmann, J.H. (1975), Measurement of insitu shear strength, keynote lecture, Proceedings of the conference on in-situ measurement of soil properties, June 1-4, 1975, vol. II, American Society of Civil Engineers.
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