3D Numerical Modeling of Large Piled-Raft Foundation on Clayey Soils for Different Loadings and Pile-Raft Configurations

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Material properties used in the validation (Sinha and Hanna 2016)

Material	Properties	Unit	Value
Soil	Young’s modulus, Es	MPa	54
	Poisson’s ratio, νs	-	0.15
	Unit weight, γ	kPa	19
	Angle of internal friction, φ	°	20
Raft	Young’s modulus, Er	GPa	34
Pile	Young’s modulus, Ep	GPa	25
	Poisson’s ratio, νp	-	0.2

Material properties used in the parametric analysis

Material	Properties	Unit	Value
Soil	Unsaturated unit weight, γunsat	kN/m3	16
	Young’s modulus, Es	MPa	25 (Soft clay)
			82 (Stiff clay)
	Poisson’s ratio, νs	-	0.495
	Angle of internal friction, φ	°	0
	Undrained cohesion	kPa	25 (Soft clay)
			80 (Stiff clay)
Raft	Young’s modulus, Er	GPa	25
	Poisson’s ratio, νr	-	0.25
Pile	Young’s modulus, Ep	GPa	25
	Poisson’s ratio, νp	-	0.25

Pile lengths used for different pile-raft configurations

Name and no. of piles, Np	Pile length, Lp (m)
	PRC with uniform pile lengths	PRC with “W”-shaped pile lengths	PRC with “V”-shaped pile lengths
P1 (1 pile)	30	L1W = 24.46	L1V = 37.19
P2–P9 (8 piles)		L2–9W = 1.1 L1W = 26.91	L2–9V = L1V/1.1 = 33.81
P10–P25 (16 piles)		L10–25W = 1.1 L2–9W = 29.60	L10–25V = L2–9V/1.1 =30.74
P26–P49 (24 piles)		L26–49W = 1.1 L10–25W = 32.56	L26–49V = L10–25V/1.1 =27.94

Center and corner settlement for different pile-raft configurations at different pile spacings

Pile-raft configurations	Pile spacing, Sp (m)	Settlement in soft clay soil profile (mm)			Settlement in stiff clay soil profile (mm)
		Wcenter	Wcorner	Wdiff	Wcenter	Wcorner	Wdiff
PRC1(a)	3	490	474	16	160	147	41
PRC1(b)		916	891	25	157	117	40
PRC1(c)		1135	1125	10	158	119	39
PRC1(a)	7	211	121	90	144	72	72
PRC1(b)		232	116	116	150	68	82
PRC1(c)		243	162	81	139	77	62

Geometric configurations of pile-raft model for parametric analysis

Parameters	Unit	Value
Raft width, Br	m	45
Raft width, Lr	m	45
Raft thickness, tr	m	0.5, 1, 1.5, 2*
Number of piles	-	49
Pile length, Lp	m	30*
Pile spacing, Sp	m	3*, 4, 5, 6, 7
Width of pile group, Bg (Corresponding to each Sp)	m	19, 25, 31, 37, 43
Pile diameter, dp	m	1

Load carried by piles in different pile-raft configurations at different pile spacings

Pile-raft configurations	Pile spacing, Sp (m)	Soft clay: load-carried by piles, Rpile (kN)			Stiff clay: load-carried by piles, Rpile (kN)
		Rcenter	Redge	Rcorner	Rcenter	Redge	Rcorner
PRC1(a)	3	226	2076	4434	565	3010	5854
PRC1(b)		431	3125	5597	650	3640	6723
PRC1(c)		494	1272	2765	1593	1474	3360
PRC1(a)	7	6721	7036	8579	6221	6388	5031
PRC1(b)		4890	7836	9105	4728	6879	5102
PRC1(c)		7376	6309	8240	7222	5751	4799