skills for estimating

The Precast Show 2018

NPCA 1

precast.org/education

DESIGN 101

SKILLS FOR ESTIMATING

Ronald Thornton, P.E.

Precast Concrete Association of NY


OBJECTIVES

• Review basic concepts related to reinforced concrete design

• Define engineering terms necessary for concrete design

• Review ASTM standards for precast underground vaults

• Perform a real-life example concrete design


REINFORCED CONCRETE DESIGN

• Terms• Member

• Wall, Slab, Beam, Column



• Terms

• Boundary Conditions

• Simply supported

• Fixed Ends

• Cantilever

• Propped Cantilever

• Continuous Support

(+)

(+)

(+)

(+) (+)

(-) (-)

(-)

(-)

(-)



• Terms• Applied Loads

• Dead Loads

• Live Loads

• Earth Loads

• Seismic

• Hydrostatic

• Wind, Snow, ice,…..



• Terms• Load Type

Uniform or Superimposed load

Concentrated Load


NPCA 2



• Design Methodologies• Allowable Stress or Working Stress

• Most popular method up to late 60’s & early 70’s

• Simplified Theory

• All loads treated equally



• Design Methodologies• Load Factor or Ultimate Strength Design

• Design Strength > Required Strength

• FN (Nominal Strength) > U (Ultimate Strength)

• Ultimate = Factored

• Capacity > Demand

• Load factors vary by type of load

and design code, i.e. ACI or

AASHTO



• Design Methodologies• Load and Resistance Factor Design (LRFD)

• Multiple load types

• Multiple Limit States

• Based on a Complex

Reliability Model

• First AASHTO Edition 1993



• Typical Load Factors• Live Loads

• ACI 318 1.6

• ACI 318 (Appendix C) 1.7

• AASHTO 2.17

• Dead Loads

• ACI 318 1.2 (1.4 without Live Load)

• ACI 318 (Appendix C) 1.4

• AASHTO 1.3



• Strength Reduction Factor, F – A multiplier that reduces the capacity of the member for design purposes.

• ACI 318 & AASHTO• Moment = 0.90 (Box Culverts 1.0, 3-Sided 0.95)

• Shear = 0.75 (Appendix C & AASHTO = 0.85)

• Axial = 0.70



• Terms• Force

• Shear – Is greatest near the support

• Flexure – Related to bending

• Axial – Typically related to columns


NPCA 3



• Shear & Moment Diagrams• Uniform Load

Shear Diagram

Moment DiagramSimple Support

(+) Positive





• Basic Stress Formula

• P = Applied Load

• A = Area resisting the load

• M =Applied Moment

• c = Distance from Centroid to Extreme Fiber

• I = Moment-of-Inertia

𝜎 =𝑃

𝐴±𝑀 × 𝑐

𝐼

𝐼 = Τ𝑏 × ℎ3 12



• Concrete Properties• fc = Compressive Strength, psi

• vc= Allowable Shear Stress, psi

• fr =Modulus-of-Rupture, psi

• Ec =Modulus-of-Elasticity, ksi

𝑣𝑐 = 𝛽 𝑓𝑐

𝑓𝑟 = 7.5 𝑓𝑐

𝐸𝑐 = 57000 𝑓𝑐



• If fr < Mc/I• Brittle Failure



• Reinforcing Steel Properties• Yield Strength, Fy = 60,000psi

• Modulus-of-Elasticity, Ec = 29,000,000psi

• “Ductility” – Ability to stretch without breaking


NPCA 4



c

𝜀 = 0.003

𝜀𝑠 =𝐹𝑦𝐸𝑠

𝐹𝑦𝐴𝑠 𝐹𝑦𝐴𝑠

d

𝑎 = 𝛽1𝑐

𝑑 − 𝑎2

𝑀 = 𝐹𝑦𝐴𝑠 𝑑 − 𝑎2



𝐴𝑠 = 𝐴𝑟𝑒𝑎 − 𝑜𝑓 − 𝑆𝑡𝑒𝑒𝑙

Bar Size Diameter (in) Ab (in2)

3 .375 .11

4 .500 .20

5 .625 .31

6 .750 .44

7 .875 .60

8 1.00 .79

9 1.128 1.00

10 1.270 1.27

11 1.410 1.56

Source: Concrete Reinforcing Steel Institute - CRSI



Beam

(3) # 6 Bars

𝐴𝑠 = 𝐴𝑏 × 𝑁𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝐵𝑎𝑟𝑠

𝐴𝑠 = 0.44 × 3 = 1.32𝑖𝑛2



Slab

#5 @ 9”oc

𝐴𝑠 =𝐴𝑏×12𝑆𝑝𝑎𝑐𝑖𝑛𝑔

𝐴𝑠 =0.31𝑖𝑛2×12"

9"=0.41𝑖𝑛2/𝑓𝑡



• Welded Wire Reinforcing• 4 x 8 W6/W3

• Longitudinal Wire Spacing (4”) x

• Transverse Wire Spacing (8”)

• W = Smooth Wire (D = Deformed Wire)

• Longitudinal Wire Size (Aw = .06in2)

• Transverse Wire Size (Aw = .03in2)

Source: Wire Reinforcing Institute - WRI



Source: Wire Reinforcing Institute - WRI

• Welded Wire Reinforcing•

• Longitudinal

• Transverse

𝐴𝑠 =𝐴𝑤×12𝑆𝑝𝑎𝑐𝑖𝑛𝑔

𝐴𝑠 =0.06𝑖𝑛2×12"

6"=0.18𝑖𝑛2/𝑓𝑡

𝐴𝑠 =0.03𝑖𝑛2×12"

8"=0.045𝑖𝑛2/𝑓𝑡


NPCA 5



• As Required – 0.40in2/ft• #4 @ 6”oc = 0.40in2/ft

• #5 @ 9”oc = 0.41in2/ft

• #6 @ 13”oc = 0.41in2/ft

• D10 @ 3”oc = 0.40in2/ft (Grade 70 Wire)



• “Serviceability”• Satisfactory Performance under normal service

conditions

• Code Related

• Ensures durability and service life

• Use unfactored loads



• “Serviceability”• Crack Control

• Limitation of Service Load Stress

• Deflection

• Fatigue

• Minimum Reinforcing Limits

• Bar Development

• Splices



• “Serviceability”• Code Related

• ACI 318 – Structural Concrete Building Code

• ACI 350 – Environmental Engineering Structures

• AASHTO Standard Specification

• AASHTO LRFD Specification

• AREMA – American Railway Engineering Manual

• CSA Canadian Standards Association



• “Serviceability”• Crack Control

• Steel Stress

• Bar Cover

• Bar Spacing

dc

Spacing Spacing

𝑧 = 𝑓𝑠3 𝑑𝑐𝐴

𝐴 = 2𝑑𝑐 × 𝑆𝑝𝑎𝑐𝑖𝑛𝑔

𝑓𝑠 = 0.6𝐹𝑦



• As Required – 0.40in2/ft; Zmax = 130kips/in• #4 @ 6”oc = 0.40in2/ft

• Z = 120kips/in OK

• #5 @ 9”oc = 0.41in2/ft• Z = 140kips/in NG

• #6 @ 13”oc = 0.41in2/ft• Z = 162kips.in NG

• D10 @ 3”oc = 0.40in2/ft (Grade 70 Wire)• Z = 92kips/in OK


NPCA 6



• “Minimum Flexural Reinforcing”• Established by Code

• ACI 318

• But not less than

• AASHTO Standard

• Same as LRFD

• Minimum waived if

• Ex: 0.40in2/ft x 1.333 = 0.53in2/ft

𝐴𝑠,𝑚𝑖𝑛 =3 𝑓′𝑐

𝑓𝑦𝑏𝑤𝑑

200𝑏𝑤𝑑/𝑓𝑦

∅𝑀𝑛 ≥ 1.2𝑀𝑐𝑟

𝐴𝑠,𝑝𝑟𝑜𝑣 ≥ 4/3𝐴𝑠,𝑟𝑒𝑞′𝑑



• “Minimum Temperature Reinforcing”• Established by Code

• ACI 318

• Slabs As min = .0018Ag Where, Ag = b * h

• Walls Horiz = .0020Ag

• Walls Vertical = .0012Ag

• Chapter 16, Precast Walls = .0010Ag

• AASHTO Standard = .125in2/ft


WORKING STRESS DESIGN

c

𝑓𝑐 𝑘𝑑/3

𝑗𝑑

𝑓𝑠

𝐸𝑐 = 57 ∗ 𝑓 ′𝑐

0.65 < 𝛽1 < 0.85

𝜌𝑏 =0.85𝑥𝛽1𝑥𝑓

′𝑐

𝐹𝑦𝑥

87,000

87,000+ 𝐹𝑦

𝑘 = 𝜌𝑛2𝑥2𝜌𝑛 − 𝜌𝑛

𝑗 = 1 − ൗ𝑘 3

𝐸𝑠 = 29,000𝑘𝑠𝑖

𝑛 = ൗ𝐸𝑠

𝐸𝑐

𝑑


EQUATIONS

• Moment Equations• Plate fixed on 3 sides, free at top (Mono Top or Base)

• M = Epavg x H2 x Coeff

• Simple Span Moment • Uniform Load,w: M = w x S2/8 x %Load

• Concentrated Load, P: M = P x S/4 x %Load

• Fixed End Moment• Uniform Load,w: M = w x S2/12 x %Load

• Concentrated Load, P: M = P x S/8 x %Load


EQUATIONS

• Shear Equations• Plate fixed on 3 sides, free at top (Mono Top or Base)

• V = Epavg x H x Coeff

• 1-Way Slab Shear • Uniform Load,w: V = w x S/2 x %Load

• Depth-to-Steel, d• dmin = V/(12 x vc)

• dactual = Thickness – Bar Cover – Db/2


EQUATIONS

• Area-of-Steel• Asreq’d = (M x 12)/(fs x j x d)• Top Slab Distribution Steel = As/S

• Concrete Stress• fc = (2M x 12)/(k x j x 12 x d2)• dactual = Thickness – Bar Cover – Db/2

• %Load• Short Direction = L3/(L3 + W3)• Long Direction = 1 - %Short Direction


NPCA 7


DESIGN EXAMPLE

Maximum Inside Dimensions Materials

Length 14.00 ft Concrete Strength, f''c 5,000 psi

Width 7.00 ft Reinforcing Steel, Fy 60,000 psi

Height 14.00 ft Concrete Density, Wc 150 pcf

Member Thickness Soil Density, Ws 120 pcf

Top Slab 8.00 in Water Density, Ww 62.4 pcf

Walls 8.00 in

Base Slab 8.00 in Allowable Stresses

Base Extension 6.00 in Concrete, fc = 0.45f'c = 2,250 psi

AASHTO ASTM Steel, fs = 0.40Fy = 24,000 psi

Design Live Load HS20 A-16 Shear, vc = 1.05f'c = 74 psi

Live Load Designations

ASTM AASHTO Wheel Load

A-16 HS20 16,000.00 lbs

A-12 HS15 12,000.00 lbs

A-8 H10 8,000.00 lbs

Minimum Slab Thickness AASHTO Table 8.9.2

[(S + 10)/30]*12 = 6.8” 6 1/2" Min


DESIGN EXAMPLE

Design Constants Table

f'c fs vc Ec n b1 .25rb k j

3000 1350 58 3122 9.29 0.85 0.005 0.269 0.910

3500 1575 62 3372 8.60 0.85 0.006 0.278 0.907

4000 1800 66 3605 8.04 0.85 0.007 0.286 0.905

4500 2025 70 3824 7.58 0.83 0.008 0.290 0.903

5000 2250 74 4031 7.20 0.80 0.008 0.292 0.903

6000 2700 81 4415 6.57 0.75 0.009 0.295 0.902

7000 3150 88 4769 6.08 0.70 0.010 0.296 0.901

𝐸𝑐 = 57 ∗ 𝑓 ′𝑐

0.65 < 𝛽1 < 0.85

𝜌𝑏 =0.85𝑥𝛽1𝑥𝑓

′𝑐

𝐹𝑦𝑥

87,000

87,000+ 𝐹𝑦

𝑘 = 𝜌𝑛2𝑥2𝜌𝑛 − 𝜌𝑛

𝑗 = 1 − ൗ𝑘 3

𝐸𝑠 = 29,000𝑘𝑠𝑖

𝑛 = ൗ𝐸𝑠

𝐸𝑐


DESIGN EXAMPLEAREA-OF-STEEL TABLE

BAR SIZE

3 4 5 6 7 8 9 10 11

Wgt 0.376 0.668 1.043 1.502 2.044 2.670 3.400 4.303 5.313

Db 0.375 0.500 0.625 0.750 0.875 1.000 1.125 1.250 1.375

Ab 0.11 0.20 0.31 0.44 0.60 0.79 1.00 1.27 1.56

BA

R S

PAC

ING

(in

)

4 0.33 0.60 0.93 1.32 1.80 2.37 3.00 3.81 4.68

5 0.26 0.48 0.74 1.06 1.44 1.90 2.40 3.05 3.74

6 0.22 0.40 0.62 0.88 1.20 1.58 2.00 2.54 3.12

7 0.19 0.34 0.53 0.75 1.03 1.35 1.71 2.18 2.67

8 0.17 0.30 0.47 0.66 0.90 1.19 1.50 1.91 2.34

9 0.15 0.27 0.41 0.59 0.80 1.05 1.33 1.69 2.08

10 0.13 0.24 0.37 0.53 0.72 0.95 1.20 1.52 1.87

11 0.12 0.22 0.34 0.48 0.65 0.86 1.09 1.39 1.70

12 0.11 0.20 0.31 0.44 0.60 0.79 1.00 1.27 1.56

14 0.09 0.17 0.27 0.38 0.51 0.68 0.86 1.09 1.34

16 0.08 0.15 0.23 0.33 0.45 0.59 0.75 0.95 1.17

18 0.07 0.13 0.21 0.29 0.40 0.53 0.67 0.85 1.04

Note: Maximum bar spacing shall note exceed 3x the member thickness nor 18"


DESIGN EXAMPLE

Bar Size

3000psi 4000psi 5000psi 6000psi

ld 1.3ld 1.5ld ld 1.3ld 1.5ld ld 1.3ld 1.5ld ld 1.3ld 1.5ld

3 16 21 24 14 18 21 13 17 20 12 16 18

4 22 29 33 19 25 29 17 22 26 15 20 23

5 27 35 41 24 31 36 21 27 32 19 25 29

6 33 43 50 28 36 42 25 33 38 23 30 35

7 48 62 72 42 55 63 37 48 56 34 44 51

8 55 72 83 47 61 71 42 55 63 39 51 59

9 62 81 93 54 70 81 48 62 72 44 57 66

10 70 91 105 60 78 90 54 70 81 49 64 74

11 77 100 116 67 87 101 60 78 90 55 72 83

REBAR DEVELOPMENT & LAP SPLICE TABLE


TOP SLAB DESIGN

f'c k j

Short Dir. Span = Width + Tw/12 7.67 ft 5000 .292 .903

Dead Load Dead Load

Earth Fill 240 psf Wheel Load, Pw = 16.00 kips

Concrete 100 Psf Impact, I 1.2

Other 0 psf Distribution Width, e 4.46 ft

Total 340 psf Strip Load =P+I/e 4.30 kips/ft

Bottom Face Short Direction Long Direction

Dead Load Moment 2.50 kip-ft

Live Load Moment 8.25 kip-ft

Total Moment 10.75 kip-ft

Bar Cover 1.50 in

dactual 6.13 in Dist Steel, As(req'd)

As(req'd) 0.97 in2/ft 0.35 in2/ft

Bar Size & Spacing #6 @ 5” #5 @ 9”

Conc. Stress, fc 2170 psi

As(min) 0.25 in2/ft 0.17 in2/ft

Top Face Short Direction Long Direction

As(min) in2/ft in2/ft

Bar Size & Spacing


TOP SLAB MOMENTS

TABLE OF TOTAL TOP SLAB MOMENTS

Soil Weight 120 pcf A-16 (HS20) Wheel Load 16 kips Concrete Weight 150 pcf

Span, S 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 9.50 10.00

Dist Width, e = 4+.06S 4.24 4.27 4.3 4.33 4.36 4.39 4.42 4.45 4.48 4.51 4.54 4.57 4.60

P = Pw/e 3.77 3.75 3.72 3.70 3.67 3.64 3.62 3.60 3.57 3.55 3.52 3.50 3.48

Slab Thickness (in) 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 10.00 10.00 10.00 10.00

Concrete DL, Wc (psf) 100 100 100 100 100 100 100 100 100 125 125 125 125

Fill (ft) We Imp Moment, M = (We + Wc) * S2/8 + P * Imp * S/4

0 0 1.3 5.11 5.73 6.36 6.98 7.61 8.23 8.85 9.47 10.09 10.93 11.57 12.22 12.87

1 120 1.3 5.35 6.04 6.73 7.44 8.15 8.86 9.58 10.31 11.05 12.01 12.79 13.57 14.37

2 240 1.2 5.21 5.92 6.64 7.38 8.14 8.90 9.68 10.48 11.29 12.34 13.21 14.10 15.00

3 360 1.2 5.45 6.22 7.02 7.84 8.68 9.54 10.42 11.32 12.25 13.43 14.43 15.45 16.50


NPCA 8


EARTH LOADSFinished Grade

Water Table Elevation

Surcharge Depth = 8’

LL Surcharge 0.5% wheel Load

EP(h) DryKa x Ws

EP(h) Saturated(Ww + Ka * (Ws – Ww))

Fill2.0’

3.0’


EARTH PRESSURE TABLE

Depth Lateral Earth Pressure Concrete

t-o-w b-o-w Pe topPebot Surcharge Average Weight

(ft) (ft) (psf) (psf) Y/N (psf) (psf) (lbs)

2.67 2.67 107 107 Y 80 12778

2.67 5.67 107 337 Y 80 302 13400

5.67 8.67 337 582 Y 80 540 13400

8.67 12.67 582 908 N 0 745 17866

12.67 16.67 908 1235 N 0 1072 30644

Total 88088

LL Surcharge EP(h)Dry EP(h) Saturated

0.5% Wheel Load Ka * Ws (Ww + Ka * (Ws - Ww))

80 psf 40 psf/ft 82 psf/ft

Structure Components:

Mono Top Riser Height 0.00 ft

Riser #1 Height 3.00 ft



Mono Base Riser Height 4.00 ft

Total Inside Height 14.00 ft


MONO TOP RISER DESIGNMOMENT & SHEAR COEFFICIENTS

L/H -Mx +Mx -My +My Vx Vy

0.50 0.021 0.011 0.014 0.003 0.252 0.230

0.75 0.053 0.027 0.033 0.008 0.393 0.344

1.00 0.085 0.043 0.053 0.014 0.533 0.457

1.25 0.132 0.062 0.087 0.019 0.696 0.565

1.50 0.178 0.081 0.121 0.025 0.859 0.673

1.25 0.220 0.091 0.163 0.024 0.907 0.759

2.0 0.261 0.101 0.204 0.024 0.955 0.845

2.5 0.296 0.094 0.278 0.012 1.018 0.923

3.0 0.330 0.087 0.351 0.000 1.080 1.000

3.5 0.165 0.043 0.425 0.000 0.540 1.000

4.0 0.000 0.000 0.500 0.000 0.000 1.000

Wall Length, L ft

Wall Height, Hgt ft

Wall Thickness in

Ratio W/Hgt

Average Lat Earth Pressure psf

Length

Hgt

f'c k j

Max Shear, V

dmin

Max Moment, M

Bar Cover

dactual

As(req'd)

Bar Size & Spacing

As(prov)

Conc. Stress, fC

As(min)

Outside Face Inside Face

Horiz (-) Vertical (-) Horiz (+) Vertical (+)

kips/ft

in

kip-ft

in

in

in2/ft

psi

in2/ft


MONO BASE RISER DESIGNMOMENT & SHEAR COEFFICIENTS


0.50 0.021 0.011 0.014 0.003 0.252 0.230

0.75 0.053 0.027 0.033 0.008 0.393 0.344

1.00 0.085 0.043 0.053 0.014 0.533 0.457

1.25 0.132 0.062 0.087 0.019 0.696 0.565

1.50 0.178 0.081 0.121 0.025 0.859 0.673

1.25 0.220 0.091 0.163 0.024 0.907 0.759

2.0 0.261 0.101 0.204 0.024 0.955 0.845

2.5 0.296 0.094 0.278 0.012 1.018 0.923

3.0 0.330 0.087 0.351 0.000 1.080 1.000

3.5 0.165 0.043 0.425 0.000 0.540 1.000

4.0 0.000 0.000 0.500 0.000 0.000 1.000

Wall Length, L 14.00 ft

Wall Height, Hgt 4.00 ft

Wall Thickness 8.00 in

Ratio L/Hgt 3.50

Average Lat Earth Pressure 1072 psf

Length

Hgt

f'c k j

5000 .292 .903

Max Shear, V

dmin

Max Moment, M

Bar Cover

dactual

As(req'd)

Bar Size & Spacing

As(prov)

Conc. Stress, fc

As(min)



2316 4288 kips/ft

2.61 4.82 in

2.83 7.29 0.74 0.00 kip-ft

1.50 1.50 in

5.50 6.13 6.25 in

0.28 0.66 .066 0 in2/ft

#4 @ 8” #6 @ 8” #4 @ 12” #4 @ 18”

0.30 0.66 0.20 0.13 in2/ft

710 1472 0 psi

0.22 0.25 0.25 in2/ft


RISER DESIGNS – OUTSIDE FACE

MOMENT COEFFICIENTS

W/L M(-) M(+)

0.3 0.0658 0.0592

0.4 0.0633 0.0617

0.5 0.0625 0.0625

0.6 0.0633 0.0617

0.7 0.0658 0.0592

0.8 0.0700 0.0550

0.9 0.0758 0.0492

1.00 0.0833 0.0417

Riser Number 1 2 3

Average Lat Earth Pressure 302 540 745 psf

Horiz Vert Horiz Vert Horiz Vert

Max Shear, V 2114 0 3780 0 5215 0 lbs/ft

dmin 2.38 4.26 5.87 in

Max Neg Moment, M(-) 3.70 0 6.61 0 9.13 0 kip-ft

Bar Cover - Outside Face 3.50 1.50 1.50 in

dactual - Outside Face 4.45 6.19 6.13 in

As(req'd) Corner (-) 0.43 0.59 0.82 in2/ft

Bar Size & Spacing #5 @ 8”oc #4 @ 18” #5 @ 6” #4 @ 18” #6 @ 6” #4 @ 18”

As(prov) Corner (-) 0.46 0.62 0.88 in2/ft

Conc. Stress, fc 1573 1309 1843 psi

As(min) Corner (-) 0.18 0.12 0.25 0.12 0.25 0.12 in2/ft


Wall Width, W 7.00 ft

Wall Thickness 8.00 in

Ratio W/L 0.5

f'c k j

5000 .292 .903

Length

Wid

th


RISER DESIGNS – INSIDE FACE

MOMENT COEFFICIENTS

W/L M(-) M(+)

0.3 0.0658 0.0592

0.4 0.0633 0.0617

0.5 0.0625 0.0625

0.6 0.0633 0.0617

0.7 0.0658 0.0592

0.8 0.0700 0.0550

0.9 0.0758 0.0492

1.00 0.0833 0.0417

Riser Number 1 2 3

Average Lat Earth Pressure 302 540 745

Horiz Vert Horiz Vert Horiz Vert

Max Pos Moment, M(+) 3.70 0 6.61 0 9.13 0 kip-ft

Bar Cover - Inside Face 3.875 1.50 1.50 in

dactual - Inside Face 4.90 6.19 6.13 in

As(req’d) Mid-Span (+) 0.42 0.59 0.82 in2/ft

Bar Size & Spacing #5 @ 8” #5 @ 6” #4 @ 18” #6 @ 6” #4 @ 18”

As(Prov) Mid-Span (+) 0.46 0.62 0.88 in2/ft

Conc. Stress, fc 1169 1309 1843 psi

As(min) Corner (+) 0.20 0.25 0.12 0.25 0.12 in2/ft

f'c k j

5000 .292 .903

Length

Wid

th


Wall Width, W 7.00 ft

Wall Thickness, Tw 8.00 in

Ratio W/L 0.5


NPCA 9


BASE SLAB DESIGNShort Dir. Span = Width + 2Tw = 7.67 ft Base Slab Foot Print Length OD 15.33 ft

Long Dir. Span = Length + 2Tw = 14.67 ft Width OD 8.33 ft

Ratio W/L 0.5 Area = L x W 127.70 ft2

Dead Load Live Load

Earth Fill 240 psf Wheel Load, Pw 16.00 kips

Concrete * 689 psf Number Of Wheels 2

Subract Base Slab (-) 100 psf Unform Live Load ** 0.284 psf

Total Unif. Dead Load 589 psf

Hydrostatic 895 psf * = Total Concrete Wgt / Area

**= Px * Wheels / Area

% Of Load

W/L Short Dir Long Dir

0.3 0.974 0.026

0.4 0.940 0.060

0.5 0.889 0.111

0.6 0.822 0.178

0.7 0.745 0.255

0.8 0.661 0.339

0.9 0.578 0.422

1.00 0.500 0.500

As(req'd) 0.74 0.36 in2/ft

Bar Size & Spacing #6 @ 6”oc #5 @ 10”oc

As(prov) 0.88 0.37 in2/ft

Conc. Stress, fc 1647 902 psi

As(min) 0.25 0.22 in2/ft

Total Uniform Load= Max Hydrostatic or Dead Load

+ Live Load = 1179 psf

Top FaceShort

DirectionLong

Direction

Max Shear, V 3883 916 kips/ft

dmin 4.37 1.03 in

Bar Cover 1.50 2.25 in

dactual 6.13 5.44 in

Max Moment, 8.16 3.52 kip-ft

Bottom FaceShort

DirectionLong

Direction

As(min) in2/ft

Bar Size & Spacing


BUOYANCY CHECK

Bottom of Base Slab BFG 17.33 ft

Top of Cover Slab BFG 2.00 ft

Water Table BFG 3.00 ft

Structure Footprint (w/o Extension) 127.8 sf

Downward Forces

Earth Fill 30667 lbs

Concrete 88088 lbs

Soil Envelope 0 lbs

Base Extension 0 lbs

Holes 0 lbs

Other 0 lbs

Total 118755 lbs

Upward Buoyant Force 114284 lbs

Difference 4471 lbs

Req’d Safety Factor 1.1

Safety Factor 1.0 NG

SOIL

EN

VEL

OPE

SOIL

EN

VEL

OPE


REBAR & CONCRETE QTY –TOP SECTION

Top Slab 8.33 ft x 14.33 ft x 8.00 in Concrete Volume

Mark Bottom Face Bar Size/Spc Length (ft) Qty Weight

TS01 Transverse #6 @ 6”oc 8.00 35 421 lbs

TS02 Longitudinal #5 @ 9”oc 15.00 10 156 lbs

Top Face

TS03 Transverse 0 0 0 0 lbs

TS04 Longitudinal 0 0 0 0 lbs

Top Riser 0 ft x 0 ft x 0 ft x 0 in wall Concrete Volume

Mark Outside Face Bar Size/Spc Length (ft) Qty Weight Leg

TR01 Long Side Horiz lbs

TR02 Vert lbs ft

TR03 Short Side Horiz lbs ft

TR02 Vert lbs ft

Inside Face

TR04 Long Side Horiz lbs

TR05 Vert lbs

TR06 Short Side Horiz lbs

TR05 Vert lbs

Subtotal lbs

85.19cf

0.00cf

85.19cf


REBAR & CONCRETE QTY -RISERS

Riser 1 7.00 ft x 14.00 ft x 3.00 ft x 8.00 in wall Concrete Volume


R101 Long Side Horiz #5 @ 8”oc 14.00 12 175 lbs 3.00 ft

R102 Vert #4 @ 18”oc 2.83 20 38 lbs

R103 Short Side Horiz #5 @ 8”oc 13.75 12 172 lbs

R102 Vert #4 @ 18”oc 2.83 12 23 lbs

Inside Face

R104 Long Side Horiz lbs

R105 Vert lbs

R106 Short Side Horiz lbs Total

R105 Vert lbs 408 lbs




R202 Vert #4 @ 18”oc 2.83 20 38 lbs


R202 Vert #4 @ 18”oc 2.83 12 23 lbs

Inside Face

R204 Long Side Horiz #5 @ 6”oc 14.67 14 214 lbs

R205 Vert #4 @ 18”oc 2.83 20 38 lbs

R206 Short Side Horiz #5 @ 6”oc 7.67 14 112 lbs Total

R205 Vert #4 @ 18”oc 2.83 12 23 lbs 858 lbs

89.33cf

89.33cf


REBAR & CONCRETE QTY –RISERS (CONT)




R302 Vert #4 @ 18”oc 3.83 20 51 lbs


R302 Vert #4 @ 18”oc 3.83 12 31 lbs

Inside Face

R304 Long Side Horiz #6 @ 6”oc 14.67 14 379 lbs

R305 Vert #4 @ 18”oc 3.83 20 51 lbs

R306 Short Side Horiz #6 @ 6”oc 7.67 14 207 lbs Total

R305 Vert #4 @ 18”oc 3.83 12 31 lbs 1541 lbs

Subtotal 2398 lbs

119.11cf

297.78cf


REBAR & CONCRETE QTY –BASE SECTION

Bottom Slab 9.33 ft x 16.33 ft x 8.00 in Concrete Volume

Mark Top Face Bar Size/Spc Length (ft) Qty Weight Leg

BS01 Transverse #6 @ 6”oc 9.00 33 446 lbs

BS02 Longitudinal #5 @ 10”oc 16.00 11 184 lbs

Bottom Face

BS03 Transverse lbs

BS04 Longitudinal lbs

Top Riser 7.00 ft x 14.00 ft x 4.00 ft x 8.00 in wall Concrete Volume


BR01 Long Side Horiz #4 @ 8”oc 14.00 14 131 lbs

BR02 Vert #6 @ 8”oc 5.96 44 394 lbs 1.50 ft

BR03 Short Side Horiz #4 @ 8”oc 14.58 14 136 lbs 3.25 ft

BR02 Vert #6 @ 8”oc 5.96 24 215 lbs 1.50 ft

Inside Face

BR04 Long Side Horiz #4 @ 12”oc 14.00 10 98 lbs

BR05 Vert #4 @ 18”oc 5.96 20 57 lbs

BR06 Short Side Horiz #4 @ 12”oc 14.58 10 51 lbs

BR05 Vert #4 @ 18”oc 5.96 12 34 lbs

Subtotal 1746 lbs

Grand Total 4951 lbs

101.63cf

119.11cf

220.74cf

603.70cf


NPCA 10


??QUESTIONS??


DESIGN 101




DESIGN 101


PRECAST VAULT DESIGN

WORKSHEETS

Prepared By:



Client: Description:

Project Name:

Calculated By: Date:

12.0 in

Minimum Flexural Reinforcing

May be waived if As(prov) > 4/3 As(req'd)

Minimum Temperature & Shrinkage Reinforcing

Slabs As(min) = .0018 x 12 x Thickness

Walls (Horiz) As(min) = .0020 x 12 x Thickness

(Vert) As(min) = .0012 x 12 x Thickness

Es = 29000 ksi f'c fs vc Ec n β1 .25ρb k j

3000 1350 58 3122 9.29 0.85 0.005 0.269 0.910

3500 1575 62 3372 8.60 0.85 0.006 0.278 0.907

4000 1800 66 3605 8.04 0.85 0.007 0.286 0.905

4500 2025 70 3824 7.58 0.83 0.008 0.290 0.903

5000 2250 74 4031 7.20 0.80 0.008 0.292 0.903

6000 2700 81 4415 6.57 0.75 0.009 0.295 0.902

7000 3150 88 4769 6.08 0.70 0.010 0.296 0.901

Long Direction = 1 - %Short Direction

Plate Fixed on 3 sides, V = Wavg x H x Coeff

Concrete Stress, fc

fc = (2M x 12)/(k x j x 12 x d2)

Top Slab Dist Steel As = As(short)/√S

% Load

Short Direction = L3/(L

3 + W

3)

Moment Equations Shear Equations

NPCA Design 101 Rectangular Vault Design

Equations & Constants

Plate Fixed on 3 sides, M = Ep x H2 x Coeff

1-Way Slab Shear, V = W x L/2Simple Span Moments:

Uniform Load, w M = w x S2/8 x %Load

Design Constants Table

Depth-to-Steel, d

Member Design Width, b =

Concentrated Load, w M = w x S/4 x %Load

Fixed End Moments:

Uniform Load, w M = w x S2/12 x %Load

Concentrated Load, w M = w x S/8 x %Load

dmin = V/(12 x vc)

dactual = Thickness - Bar Cover - Db/2

Area-of-Steel, As

As(req'd) = M x 12/fs x j x d)

Top Slab Dist Steel As = As(short)/√S

� = ��2�� − ��

= 1 − �3�

� =0.85��

��

87,000

87,000 + ��

�� =200!⬚� #

�$

%& = 57 ∗ ��&

0.65 < �� < 0.85

%� = 29,000�+ � = %�%&

�


Project Name:


3 4 5 6 7 8 9 10 11

Wgt 0.376 0.668 1.043 1.502 2.044 2.670 3.400 4.303 5.313

Db 0.375 0.500 0.625 0.750 0.875 1.000 1.125 1.250 1.375

Ab 0.11 0.20 0.31 0.44 0.60 0.79 1.00 1.27 1.56

4 0.33 0.60 0.93 1.32 1.80 2.37 3.00 3.81 4.68

5 0.26 0.48 0.74 1.06 1.44 1.90 2.40 3.05 3.74

6 0.22 0.40 0.62 0.88 1.20 1.58 2.00 2.54 3.12

7 0.19 0.34 0.53 0.75 1.03 1.35 1.71 2.18 2.67

8 0.17 0.30 0.47 0.66 0.90 1.19 1.50 1.91 2.34

9 0.15 0.27 0.41 0.59 0.80 1.05 1.33 1.69 2.08

10 0.13 0.24 0.37 0.53 0.72 0.95 1.20 1.52 1.87

11 0.12 0.22 0.34 0.48 0.65 0.86 1.09 1.39 1.70

12 0.11 0.20 0.31 0.44 0.60 0.79 1.00 1.27 1.56

14 0.09 0.17 0.27 0.38 0.51 0.68 0.86 1.09 1.34

16 0.08 0.15 0.23 0.33 0.45 0.59 0.75 0.95 1.17

18 0.07 0.13 0.21 0.29 0.40 0.53 0.67 0.85 1.04

l d 1.3l d 1.5l d l d 1.3l d 1.5l d l d 1.3l d 1.5l d l d 1.3l d 1.5l d

3 16 21 24 14 18 21 13 17 20 12 16 18

4 22 29 33 19 25 29 17 22 26 15 20 23

5 27 35 41 24 31 36 21 27 32 19 25 29

6 33 43 50 28 36 42 25 33 38 23 30 35

7 48 62 72 42 55 63 37 48 56 34 44 51

8 55 72 83 47 61 71 42 55 63 39 51 59

9 62 81 93 54 70 81 48 62 72 44 57 66

10 70 91 105 60 78 90 54 70 81 49 64 74

11 77 100 116 67 87 101 60 78 90 55 72 83

Note: Use 1.5l d for epoxy bar

REBAR DEVELOPMENT & LAP SPLICE TABLE

3000psi 4000psi 5000psi 6000psiBar

Size


Note: Maximum bar spacing shall note exceed 3x the member thickness nor 18"

BA

R S

PA

CIN

G (

in)

BAR SIZE

AREA-OF-STEEL TABLE


Project Name:


ft psi

ft psi

ft pcf

pcf

in pcf

in

in

in Concrete, fc = 0.45f'c = psi

psi

psi

ft

ft

t-o-w b-o-w Pe top Pe bot

(ft) (ft) (psf) (psf) Y/N (psf)

ft

ft

ft

ft

ft

ft

Earth Fill

Water Table Depth

Member Thickness

Top Slab

Walls

Base Slab

Steel, fs = 0.40Fy =

Shear, vc = 1.05√f'c =

Materials

Allowable Stresses

Concrete Strength, f''c

Reinforcing Steel, Fy

Concrete Density, Wc

Soil Density, Ws

Water Density, Ww

Rectangular Vault Design

Input

NPCA Design 101

Maximum Inside Dimensions

Length

Width

Height

(lbs)

Surcharge

Lateral Earth Pressure

Base Extension

Design Live Load

Depth Concrete

Weight

AASHTO ASTM

Mono Top Riser Height

Riser #1 Height

Riser #2 Height

Riser #3 Height

Mono Base Riser Height

Structure Components:

Average

(psf)

Total Inside Height Total


Project Name:


Fill ft

W/T ft

psf psf/ft psf/ft

Lateral Soil Pressure

Finished Grade

Water Table Elevation

Surcharge Depth = 8'

LL Surcharge


0.5% Wheel Load

EP(h)Dry

Ka * Ws

EP(h) Saturated

(Ww + Ka * (Ws - Ww))


Project Name:


f'c k j

ft

psf kips

psf

psf ft

psf kips/ft

Bottom Face

kip-ft

kip-ft

kip-ft

in

in

in2/ft in

2/ft

in2/ft

psi

in2/ft

Top Face

in2/ft

in2/ft

Note: Top face required for temperature & shrinkage if thickness > 10"

Bar Size & Spacing

As(prov)

Dead Load Moment


Top Slab Design - Concentrated Load

As(req'd)

Total

Dead Load Live Load

Wheel Load, Pw =

Impact, I

Distribution Width, e

Strip Load =P+I/e

Earth Fill

Concrete

Other

Short Direction Long Direction

Dist Steel, As(req'd) = As (short)/√S

Short Dir. Span = Width + Tw/12 =

Live Load Moment

Total Moment

Bar Cover

dactual

Bar Size & Spacing

Conc. Stress, fc

As(min)

As(prov)


As(min)


Project Name:


120 pcf 16 kips 150 pcf

4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 9.50 10.00

4.24 4.27 4.3 4.33 4.36 4.39 4.42 4.45 4.48 4.51 4.54 4.57 4.60

3.77 3.75 3.72 3.70 3.67 3.64 3.62 3.60 3.57 3.55 3.52 3.50 3.48

8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 8.00 10.00 10.00 10.00 10.00

100 100 100 100 100 100 100 100 100 125 125 125 125

Fill (ft) We Imp

0.0 0 1.3 5.11 5.73 6.36 6.98 7.61 8.23 8.85 9.47 10.09 10.93 11.57 12.22 12.87

1.0 120 1.3 5.35 6.04 6.73 7.44 8.15 8.86 9.58 10.31 11.05 12.01 12.79 13.57 14.37

2.0 240 1.2 5.21 5.92 6.64 7.38 8.14 8.90 9.68 10.48 11.29 12.34 13.21 14.10 15.00

3.0 360 1.1 5.07 5.80 6.55 7.33 8.13 8.94 9.79 10.65 11.54 12.67 13.63 14.62 15.63

lbs

lbs

lbs

TABLE OF TOTAL TOP SLAB MOMENTS

A-16 (HS20) Wheel Load Concrete Weight


Soil Weight

[(S + 10)/30]*12 =

Minimum Slab Thickness AASTO Table 8.9.2

6 1/2" MinLive Load Designations

Span, S

Dist Width, e = 4+.06S

Moment, M = (We + Wc) * S2/8 + P * Imp * S/4

P = Pw/e

Slab Thickness (in)

Concrete DL, Wc (psf)

ASTM AASHTO Wheel Load

A-16 HS20 16,000.00

A-12 HS15 12,000.00

A-8 H10 8,000.00


Project Name:


Length


0.50 0.021 0.011 0.014 0.003 0.252 0.230

0.75 0.053 0.027 0.033 0.008 0.393 0.344

Hgt 1.00 0.085 0.043 0.053 0.014 0.533 0.457

1.25 0.132 0.062 0.087 0.019 0.696 0.565

1.50 0.178 0.081 0.121 0.025 0.859 0.673

1.25 0.220 0.091 0.163 0.024 0.907 0.759

2.0 0.261 0.101 0.204 0.024 0.955 0.845

Wall Length, L ft 2.5 0.296 0.094 0.278 0.012 1.018 0.923

Wall Height, H ft 3.0 0.330 0.087 0.351 0.000 1.080 1.000

Wall Thickness, Tw in 3.5 0.165 0.043 0.425 0.000 0.540 1.000

Ratio L/Hgt 4.0 0.000 0.000 0.500 0.000 0.000 1.000


f'c k j

lbs/ft

in

kip-ft

in

in

in2/ft

in2/ft

psi

in2/ft




Mono Top Design

MOMENT & SHEAR COEFFICIENTS

As(req'd)

Bar Size & Spacing

Conc. Stress, fc

As(min)

Max Shear, V

dmin

Max Moment, M

Bar Cover

dactual

As(prov)


Project Name:


Length

W/L

0.3

0.4

0.5

0.6

0.7

0.8

ft 0.9

ft 1.00

in f'c k j

0

0

MOMENT COEFFICIENTS

M(-) M(+)

0.0700 0.0550


Riser Designs

0.0658 0.0592

0.0633 0.0617

0.0625 0.0625

0.0633 0.0617

0.0658 0.0592

Wall Width, W

Wall Thickness

Ratio W/L

0

0.0492

0.0833 0.0417

0.0758Wall Length, L

0

1

Horiz Vert

As(Prov) Mid-Span (+)

Conc. Stress, fc

3

Horiz Vert

Riser Number

Average Lat Earth Pressure

Max Shear, V

dmin

Outside Face

Max Neg Moment, M(-)

Bar Cover - Outside Face

dactual

As(req'd) Corner (-)

Bar Size & Spacing

As(prov) Corner (-)

Conc. Stress, fc

As(min) Corner (-)

Inside Face

Max Pos Moment, M(+)

Bar Cover - Inside Face

dactual

As(min) Mid-Span (+)

Bar Size & Spacing

As(min) Corner (+)

Horiz Vert

2

Horiz Vert

0

0

Horiz Vert

0

0

0

Wid

th

0

Horiz Vert

0

0


Project Name:


Length


0.50 0.021 0.011 0.014 0.003 0.252 0.230

0.75 0.053 0.027 0.033 0.008 0.393 0.344

Hgt 1.00 0.085 0.043 0.053 0.014 0.533 0.457

1.25 0.132 0.062 0.087 0.019 0.696 0.565

1.50 0.178 0.081 0.121 0.025 0.859 0.673

1.25 0.220 0.091 0.163 0.024 0.907 0.759

2.0 0.261 0.101 0.204 0.024 0.955 0.845

Wall Length, L ft 2.5 0.296 0.094 0.278 0.012 1.018 0.923

Wall Height, H ft 3.0 0.330 0.087 0.351 0.000 1.080 1.000

Wall Thickness, Tw in 3.5 0.165 0.043 0.425 0.000 0.540 1.000

Ratio L/Hgt 4.0 0.000 0.000 0.500 0.000 0.000 1.000


f'c k j

lbs/ft

in

kip-ft

in

in

in2/ft

in2/ft

psi

in2/ft

As(req'd)

Bar Size & Spacing

As(prov)

Conc. Stress, fc

As(min)

Max Shear, V

dmin

Max Moment, M

Bar Cover

dactual

Outside Face

Horiz (-) Vertical (-)

Inside Face

Horiz (+) Vertical (+)

MOMENT & SHEAR COEFFICIENTS



Project Name:


ft ft

ft ft

ft2

psf kips/ft

psf

(-) psf psf

psf

psf

f'c k j

psf

kips/ft

in W/L

in 0.3

in 0.4

kip-ft 0.5

in2/ft 0.6

0.7

in2/ft 0.8

psi 0.9

in2/ft 1.00

kips/ft

in

in2/ft

Note: Bottom face required for temperature & shrinkage if thickness > 10"

As(prov)

Conc. Stress, fc

As(min)

Top Face

Bottom Face Short Direction Long Direction

As(min)

Max Shear, V

dmin

Bar Cover

dactual

Max Moment, M

As(req'd)

Bar Size & Spacing

As(prov) 0.661 0.339

0.578 0.422

0.500 0.500

0.026

0.940 0.060

0.889 0.111

0.822 0.178

0.745 0.255

Length OD

Width OD

Area = L x W

% Of Load

Short Dir Long Dir


Base Slab Design


Concrete *

Subract Base Slab

Hydrostatic

Base Slab Foot Print

Live Load

Wheel Load, Pw

Number Of Wheels

Unform Live Load **

Total Unif. Dead Load

Short Dir. Span = Width + 2Tw =

Long Dir. Span = Length + 2Tw =

Ratio W/L

Dead Load

Earth Fill

0.974

Bar Size & Spacing

* = Total Concrete Wgt / Area

**= Px * Wheels / Area

Total Uniform Load

= Max Hydrostatic or Dead Load

+ Live Load =


Project Name:


ft

ft

ft

sf

lbs

lbs

lbs

lbs

lbs

lbs

lbs

lbs

lbsDifference

Safety Factor

Other

Total

Upward Buoyant Force

Soil Envelope

Base Extension

Holes

Bottom of Base Slab BFG

Top of Cover Slab BFG

Water Table BFG

Structure Footprint (w/o Extension)

Downward Forces

Rectangular Vault Design

Buoyancy Check

NPCA Design 101

Earth Fill

Concrete

EARTH FILL

SO

IL E

NV

ELO

PE

SO

IL E

NV

ELO

PE


Project Name:


ft x ft x in Concrete Volume cf

Mark Qty

TS01 lbs

TS02 lbs

TS03 lbs

TS04 lbs

Top Riser ft x ft x ft x in wall Concrete Volume cf

Mark Qty

TR01 lbs

TR02 lbs ft

TR03 lbs ft

TR02 lbs ft

TR04 lbs

TR05 lbs

TR06 lbs

TR05 lbs

lbs

Concrete Subtotal cf

Reinforcing Subtotal

Leg

Leg

Vert

Horiz

Short Side

Bar Size/Spc Length (ft)

Vert

Short Side

Transverse

Longitudinal

Transverse

Longitudinal

Bottom Face

Top Face

Horiz

Vert

Inside Face

Long Side

Horiz

Vert

Bar Size/Spc Length (ft)

Horiz

Outside Face Weight

Long Side

Top Slab

Weight



Project Name:


Riser 1 ft x ft x ft x in wall Concrete Volume cf

Mark Qty

R101 lbs ft

R102 lbs

R103 lbs

R102 lbs

R104 lbs

R105 lbs

R106 lbs

R105 lbs lbs


Mark Qty

R201 lbs ft

R202 lbs

R203 lbs

R202 lbs

R204 Long Side IF lbs

R205 lbs

R206 Short Side IF lbs

R205 lbs lbs


Mark Qty

R301 lbs ft

R302 lbs

R303 lbs

R302 lbs

R304 lbs

R305 lbs

R306 lbs

R305 lbs lbs

lbs


Inside Face


Total

Long Side

Short Side

Short Side

Short Side

Total

Outside Face Bar Size/Spc Length (ft) Weight Leg

Total

Outside Face Bar Size/Spc Length (ft) Weight Leg

Inside Face

Long Side

Long Side Horiz

Horiz

Vert

Horiz

Vert

Bar Size/SpcOutside Face

Inside Face

Weight Leg

Vert

Vert

Horiz

Vert

Horiz

Vert

Horiz


Long Side

Vert

Horiz

Vert

Short Side

Horiz

Vert

Length (ft)

Long Side

Short Side

Horiz

Vert

Horiz

Horiz

Vert

Horiz

Vert


Project Name:


ft x ft x in Concrete Volume cf

Mark Qty

BS01 lbs

BS02 lbs

BS03 lbs

BS04 lbs

Base Riser ft x ft x ft x in wall Concrete Volume cf

Mark Qty

BR01 lbs

BR02 lbs ft

BR03 lbs ft

BR02 lbs ft

BR04 lbs

BR05 lbs

BR06 lbs

BR05 lbs

lbs

lbs


Total Concrete Volume cf

Grand Total

Vert


Vert

Short Side Horiz

Inside Face

Long Side Horiz

Short Side Horiz

Vert

Vert

Long Side Horiz

Leg

Bottom Face

Transverse

Longitudinal

Outside Face Bar Size/Spc Length (ft) Weight

Transverse

Longitudinal

Leg


Bottom Slab

Top Face Bar Size/Spc Length (ft) Weight

skills for estimating

Documents