calcnote ACI 318-19
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Continuous beam result

14.0 × 28.0 in 4-#8 f′c 4000 psi fy 60.0 ksi d 25.62 in 4 spans
PASS

All 10 critical sections pass: flexure, shear, crack control, development, deflection.

Input summary

Span L (ft) wD (klf) wL (klf)
Span 1 22.0 2.0 1.2
Span 2 22.0 2.0 1.2
Span 3 22.0 2.0 1.2
Span 4 22.0 2.0 1.2
Supports: pin (left), pin (right); interior: continuous (pinned)

Moment and shear envelopes

Moment Envelope (kip-ft) 226.4 -265.0 Shear Envelope (kip) 69.2 -69.2

Pattern loading skipped (L/D ≤ 0.75 per ACI 6.4.3): single full-load case analyzed.

Critical sections

Location Mu (kip-ft) Vu (kip) Type Status
Span 1 midspan 185.5 0.7 rectangular PASS
Span 1 right support 224.0 48.5 rectangular PASS
Span 2 midspan 87.2 1.4 rectangular PASS
Span 2 left support 224.0 41.7 rectangular PASS
Span 2 right support 149.3 34.9 rectangular PASS
Span 3 midspan 87.2 1.4 rectangular PASS
Span 3 left support 149.3 34.9 rectangular PASS
Span 3 right support 224.0 41.7 rectangular PASS
Span 4 midspan 185.5 0.7 rectangular PASS
Span 4 left support 224.0 48.5 rectangular PASS
Span 1 midspan PASS

Section type: rectangular (positive moment, flange in compression)

D/C moment 0.55
φMn (kip-ft)
336.1
Mu (kip-ft)
185.5
D/C shear 0.01
φVn (kip)
65.7
Vu (kip)
0.7
Crack control: PASS
D/C development 0.25
ld,adj (in)
24.5
lavail (in)
99.6
ψt
1.00
Bar dia. limit (9.7.3.8.3): PASS
Span 1 right support PASS

Section type: rectangular (negative moment, rectangular)

D/C moment 0.67
φMn (kip-ft)
336.1
Mu (kip-ft)
224.0
D/C shear 0.74
φVn (kip)
65.7
Vu (kip)
48.5
Crack control: PASS
D/C development 0.77
ld,adj (in)
38.8
lavail (in)
50.4
ψt
1.30
Span 2 midspan PASS

Section type: rectangular (positive moment, flange in compression)

D/C moment 0.26
φMn (kip-ft)
336.1
Mu (kip-ft)
87.2
D/C shear 0.02
φVn (kip)
65.7
Vu (kip)
1.4
Crack control: PASS
D/C development 0.11
ld,adj (in)
12.0
lavail (in)
112.8
ψt
1.00
Bar dia. limit (9.7.3.8.3): PASS
Span 2 left support PASS

Section type: rectangular (negative moment, rectangular)

D/C moment 0.67
φMn (kip-ft)
336.1
Mu (kip-ft)
224.0
D/C shear 0.63
φVn (kip)
65.7
Vu (kip)
41.7
Crack control: PASS
D/C development 0.61
ld,adj (in)
38.8
lavail (in)
64.1
ψt
1.30
Span 2 right support PASS

Section type: rectangular (negative moment, rectangular)

D/C moment 0.44
φMn (kip-ft)
336.1
Mu (kip-ft)
149.3
D/C shear 0.53
φVn (kip)
65.7
Vu (kip)
34.9
Crack control: PASS
D/C development 0.56
ld,adj (in)
25.4
lavail (in)
45.3
ψt
1.30
Span 3 midspan PASS

Section type: rectangular (positive moment, flange in compression)

D/C moment 0.26
φMn (kip-ft)
336.1
Mu (kip-ft)
87.2
D/C shear 0.02
φVn (kip)
65.7
Vu (kip)
1.4
Crack control: PASS
D/C development 0.11
ld,adj (in)
12.0
lavail (in)
112.8
ψt
1.00
Bar dia. limit (9.7.3.8.3): PASS
Span 3 left support PASS

Section type: rectangular (negative moment, rectangular)

D/C moment 0.44
φMn (kip-ft)
336.1
Mu (kip-ft)
149.3
D/C shear 0.53
φVn (kip)
65.7
Vu (kip)
34.9
Crack control: PASS
D/C development 0.56
ld,adj (in)
25.4
lavail (in)
45.3
ψt
1.30
Span 3 right support PASS

Section type: rectangular (negative moment, rectangular)

D/C moment 0.67
φMn (kip-ft)
336.1
Mu (kip-ft)
224.0
D/C shear 0.63
φVn (kip)
65.7
Vu (kip)
41.7
Crack control: PASS
D/C development 0.61
ld,adj (in)
38.8
lavail (in)
64.1
ψt
1.30
Span 4 midspan PASS

Section type: rectangular (positive moment, flange in compression)

D/C moment 0.55
φMn (kip-ft)
336.1
Mu (kip-ft)
185.5
D/C shear 0.01
φVn (kip)
65.7
Vu (kip)
0.7
Crack control: PASS
D/C development 0.25
ld,adj (in)
24.5
lavail (in)
99.6
ψt
1.00
Bar dia. limit (9.7.3.8.3): PASS
Span 4 left support PASS

Section type: rectangular (negative moment, rectangular)

D/C moment 0.67
φMn (kip-ft)
336.1
Mu (kip-ft)
224.0
D/C shear 0.74
φVn (kip)
65.7
Vu (kip)
48.5
Crack control: PASS
D/C development 0.77
ld,adj (in)
38.8
lavail (in)
50.4
ψt
1.30

Deflection

PASS
Span Ie,avg (in4) δD (in) δL (in) δLT (in) L/δ Status
span_1 13590 0.089 0.054 0.232 1137 PASS
span_2 16564 0.035 0.021 0.092 2876 PASS
span_3 16564 0.035 0.021 0.092 2876 PASS
span_4 13590 0.089 0.054 0.232 1137 PASS
Weighted-average Ie per ACI 435.3R-68 (0.70·Ie,mid + 0.15·(Ie,left + Ie,right)); Bischoff Ie per ACI 24.2.3.5.
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2-span sample 3-span sample
Calculated 2026-10-26 · ACI 318-19