Footing result

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Isolated footing 96 × 96 × 20 in qa 5 ksf f′c 4,000 psi fy 60 ksi #6 bottom bars d 16.62 in

INCOMPLETE

No check failed, but one or more checks could not be completed. See the warnings below.

Soil bearing, overturning and sliding

PASS

D/C bearing (q max / q net) 0.91

q_max (maximum service pressure): 4.12 ksf
q_net (net allowable pressure): 4.51 ksf

Quantity	Value
q_max (maximum pressure, ksf)	4.12
q_min (minimum pressure, ksf)	2.13
q_net (qa less overburden and self-weight, ksf)	4.51
e_L (eccentricity from M_L, in)	5.10
B/6 (kern limit for e_L, in)	16.00
e_B (eccentricity from M_B, in)	0.00
L/6 (kern limit for e_B, in)	16.00
Footing self-weight (kip)	16.00
Soil weight above footing (kip)	15.36
M_resist (resisting moment, kip-ft)	925.44
M_overturn (overturning moment, kip-ft)	85.00
F_resist (friction resistance, kip)	100.00
FS_ot (overturning factor of safety, minimum 1.5)	10.89
FS_slide (sliding factor of safety, minimum 1.5)	N/A (no lateral force)
Bearing (q_max ≤ q_net)	Satisfied
Kern (e within B/6 and L/6, full contact)	Within kern
Overturning (FS ≥ 1.5)	Satisfied
Sliding (FS ≥ 1.5)	Satisfied

Service loads; friction-only sliding resistance ACI 318-19 §13.2.1 · §13.2.2

Flexure

PASS

L-direction bars (parallel to L)

D/C moment 0.67

φMn (design moment capacity): 258.22 kip-ft
Mu (factored moment at column face): 175.49 kip-ft

Quantity	Value
b (design width, in)	96.0
d (effective depth, in)	16.62
A_s,req (steel required for M_u, in²)	2.38
A_s,min (minimum steel, in², §13.3.3.2)	3.46
Bars (number of #6 bars)	8
A_s,prov (steel provided, in²)	3.52
s (center-to-center spacing, in)	12.75
Clear spacing (in, minimum max(d_b, 1 in), §25.2.1)	12.00
a (stress block depth, in)	0.65
φMn (design moment strength, kip-ft)	258.22
Status	PASS

B-direction bars (parallel to B)

D/C moment 0.71

φMn (design moment capacity): 246.34 kip-ft
Mu (factored moment at column face): 175.49 kip-ft

Quantity	Value
b (design width, in)	96.0
d (effective depth, in)	15.88
A_s,req (steel required for M_u, in²)	2.49
A_s,min (minimum steel, in², §13.3.3.2)	3.46
Bars (number of #6 bars)	8
A_s,prov (steel provided, in²)	3.52
s (center-to-center spacing, in)	12.75
Clear spacing (in, minimum max(d_b, 1 in), §25.2.1)	12.00
a (stress block depth, in)	0.65
φMn (design moment strength, kip-ft)	246.34
Status	PASS

γ_s (fraction of short-direction steel in the central band, §13.3.3.3)

1.000

φ = 0.90; critical section at the column face ACI 318-19 §13.2.7.1 · Table 21.2.2 · §25.2.1

One-way shear

PASS

L-direction bars (critical section parallel to B)

D/C shear 0.79

φVc (design shear capacity): 78.83 kip
Vu (factored shear at d from the face): 62.34 kip

Quantity	Value
ρ_w (A_s,prov / (b_w·d))	0.0022
V_c (concrete shear strength, kip)	105.11
φV_c (design shear strength, kip)	78.83
V_u (factored shear, kip)	62.34
Status	PASS

B-direction bars (critical section parallel to L)

D/C shear 0.84

φVc (design shear capacity): 76.45 kip
Vu (factored shear at d from the face): 64.53 kip

Quantity	Value
ρ_w (A_s,prov / (b_w·d))	0.0023
V_c (concrete shear strength, kip)	101.93
φV_c (design shear strength, kip)	76.45
V_u (factored shear, kip)	64.53
Status	PASS

φ = 0.75; no shear reinforcement ACI 318-19 §13.2.7.2 · Table 22.5.5.1

Punching shear

NOT CHECKED (eccentric loading)

Eccentric loading is not verified. The D/C below is the concentric check only and does not include moment transfer.

D/C punching shear 0.53

φVc (design punching capacity): 447.07 kip
Vu (factored punching demand): 240.08 kip

Quantity	Value
d_avg (average effective depth, in)	16.25
b_o (critical perimeter at d/2, in)	145.0
Area inside perimeter (in²)	1,314
β (long side / short side of column)	1.00
α_s (location factor, §22.6.5.3)	40
v_c (a) (4λ_sλ√f′c, psi)	253.0
v_c (b) ((2 + 4/β)λ_sλ√f′c, psi)	379.5
v_c (c) ((2 + α_sd/b_o)λ_sλ√f′c, psi)	410.0
v_c governing (minimum of (a), (b), (c), psi)	253.0
V_c (v_c·b_o·d, kip)	596.09
φV_c (design punching strength, kip)	447.07
Critical perimeter fits in the footing	Yes

φ = 0.75; concentric loading only ACI 318-19 §22.6.4.1 · Table 22.6.5.2

Development length

PASS

L-direction bars

D/C development length 0.34

Quantity	Value
l_d (development length, in)	17.1
l_d adjusted (reduced for excess steel, minimum 12 in, in)	12.0
l_avail (available length beyond the critical section, in)	35.0
c_b (cover or half spacing term, in)	3.38
ψ_t (casting position)	1.00
ψ_e (coating)	1.00
ψ_s (bar size)	0.80
ψ_g (grade)	1.00
Status	PASS

B-direction bars

D/C development length 0.34

Quantity	Value
l_d (development length, in)	17.1
l_d adjusted (reduced for excess steel, minimum 12 in, in)	12.1
l_avail (available length beyond the critical section, in)	35.0
c_b (cover or half spacing term, in)	3.38
ψ_t (casting position)	1.00
ψ_e (coating)	1.00
ψ_s (bar size)	0.80
ψ_g (grade)	1.00
Status	PASS

Straight bars in tension, no hooks ACI 318-19 §13.2.7.1 · Eq. 25.4.2.4a · Table 25.4.2.5

Column to footing interface

PASS

D/C bearing on concrete 0.15

φB_n (design bearing strength): 1,768.00 kip
Pu (factored load): 280.00 kip

Quantity	Value
A₁ (loaded area, in²)	400
A₂ (supporting area (frustum base), in²)	3,600
φB_n (design bearing strength, kip, §22.8.3.2)	1,768.00
A_s,dowel,min (minimum dowel area, in², §16.3.4.1)	2.00

Feasible dowel sizes

Sizes whose compression development length fits in the footing depth. A design aid; detailing is the engineer’s responsibility.

Bar	Number	l_dc (in)
#4	10	9.5
#5	7	11.9
#6	5	14.2

φ = 0.65 for bearing ACI 318-19 §22.8.3.2 · §16.3.4.1 · §25.4.9.2

Warnings

Punching shear not verified for eccentric loading; a detailed Jc analysis is required.

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