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Design of Precast BoxDesign of Precast BoxDesign of Precast Box Design of Precast Box Culverts to AASHTO LRFDCulverts to AASHTO LRFD

Josh BeakleyJosh BeakleyOctober, 2010October, 2010

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LRFD is Coming

AASHTO LRFD Bridge DesignAASHTO LRFD Bridge Design Specifications Section 3 Section 3 –– Loads and Load FactorsLoads and Load Factors Section 4Section 4 –– Structural Analysis andStructural Analysis and Section 4 Section 4 Structural Analysis and Structural Analysis and

EvaluationEvaluation Section 5Section 5 Concrete StructuresConcrete Structures Section 5 Section 5 –– Concrete StructuresConcrete Structures Section 12 Section 12 –– Buried Structures and Tunnel Buried Structures and Tunnel

LiLiLinersLiners

Outline

LoadsLoads VerticalVertical HorizontalHorizontal Load FactorsLoad Factors

CapacityCapacity ResearchResearchesea cesea c ASTM Standards ASTM Standards –– C 1577 (C 1433)C 1577 (C 1433)

Loads

Vertical LoadsVertical Loads Horizontal LoadsHorizontal Loads Horizontal LoadsHorizontal Loads Reaction Loads Reaction Loads

L d F tL d F t Load Factors Load Factors Load ModifiersLoad Modifiers

Vertical Loads

Live LoadsLive Loads Impact FactorImpact Factor Impact FactorImpact Factor

Dead LoadsDead LoadsE th L dE th L d Earth LoadsEarth Loads

Live Load Spacing – HL-934000 lb.

14 f6 f

12,500 lb. 12,500 lb.

14 ft.6 ft.

12,500 lb. 12,500 lb.

16000 lb. 16000 lb.

AASHTO AASHTO (12,00 lb per STD)

HS 20 LOAD ALTERNATE LOAD

Live Load Shallow CoverLive Load Shallow Cover

Depth of Fill Less Than 2 FeetDepth of Fill Less Than 2 Feet

Lane Load – Not Required LRFDLRFD –– 20042004 –– Truck and Lane LoadTruck and Lane Load LRFD LRFD 2004 2004 Truck and Lane LoadTruck and Lane Load

64 lbs across a 10 ft width64 lbs across a 10 ft widthDLA not appliedDLA not appliedDLA not appliedDLA not applied

LRFD LRFD –– 2005 2005 –– Truck onlyTruck onlyLRFDLRFD F tF t ?? LRFD LRFD –– Future Future –– ??

Standard Specification Standard Specification –– 3.7.1.13.7.1.1Either truck or Lane LoadEither truck or Lane LoadTruck governs for shorter spansTruck governs for shorter spans

Axle Width

Distribution Width

LRFD (4.6.2.10)LRFD (4.6.2.10)E = 96 + 1.44S (for axle)E = 96 + 1.44S (for axle)E 96 + 1.44S (for axle)E 96 + 1.44S (for axle)E in inches and S in feetE in inches and S in feet

St d d (3 24 3 2)St d d (3 24 3 2) Standard (3.24.3.2)Standard (3.24.3.2)E = 4 + 0.06S (for wheel)E = 4 + 0.06S (for wheel)E in feet and S in feetE in feet and S in feet

Distribution Width

Distribution Steel

Dynamic Load Allowance

LRFD LRFD –– Dynamic Load Allowance (3.6.2.2)Dynamic Load Allowance (3.6.2.2)DLA = 0.33(1.0DLA = 0.33(1.0 -- 0.125D0.125DEE))DLA 0.33(1.0 DLA 0.33(1.0 0.125D0.125DEE))

Standard Standard –– Impact Factor (3.8.2.3)Impact Factor (3.8.2.3)IM 0 3IM 0 3 0’0’ 0” t 1’0” t 1’ 0” INCL0” INCL IM = 0.3 IM = 0.3 –– 0’0’--0” to 1’0” to 1’--0” INCL.0” INCL.

IM = 0.2 IM = 0.2 –– 1’1’--1” to 2’1” to 2’--0” INCL.0” INCL. IM = 0.1 IM = 0.1 –– 2’2’--1” to 2’1” to 2’--11” INCL.11” INCL.

Live Load H ≥ 2ft

Tire Footprint

LRFD LRFD –– 3.6.1.2.63.6.1.2.6w=20”w=20”w 20w 20 l=10”l=10”

Live Load Area for Depths ≥ 2 ft.

LRFD (3.6.1.2.6) LRFD (3.6.1.2.6) AALL = (20/12 + 1.15D= (20/12 + 1.15DEE)(10/12 + 1.15D)(10/12 + 1.15DEE))AALL (20/12 + 1.15D (20/12 + 1.15DEE)(10/12 + 1.15D)(10/12 + 1.15DEE))

1.15 above should be replaced with 1.0 1.15 above should be replaced with 1.0 if select granular backfill is not usedif select granular backfill is not usedif select granular backfill is not usedif select granular backfill is not used

Standard (6.4.1)Standard (6.4.1)AALL = (1.75D= (1.75DEE))22

How Far Down?

3.6.1.2.63.6.1.2.6 “For single“For single--span culverts, the effects of livespan culverts, the effects of live For singleFor single span culverts, the effects of live span culverts, the effects of live

load may be neglected where the depth of load may be neglected where the depth of fill is more than 8.0 ft and exceeds the spanfill is more than 8.0 ft and exceeds the spanfill is more than 8.0 ft and exceeds the span fill is more than 8.0 ft and exceeds the span length;”length;”

Dead Load (Structural Load)

LRFD LRFD –– 3.5.13.5.1 concconc = 140pcf + = 140pcf + co cco c

1pcf (f1pcf (f ’’cc in kips)in kips)

Standard Standard –– 3.3.63.3.6 concconc = 150pcf= 150pcfconcconc pp

Earth Load

LRFD LRFD –– 12.10 12.10 γγss ≥ 110 pcf≥ 110 pcfss

Standard Standard –– 6.2.16.2.1 γγss = 120 pcf= 120 pcf

Dead Loads 3 5 1Dead Loads – 3.5.1

Embankment Installation

FrictionalSoil P i

ForcesPrism

N t l G dNatural Ground

Vertical Arching Factor

WWEE = F= FeessBBccHHFFee = 1 + 0.20(H/B= 1 + 0.20(H/Bcc))ee (( cc))FFee shall not exceed 1.15 for installations shall not exceed 1.15 for installations

with compacted fill along the sides of the with compacted fill along the sides of the p gp gbox section, or 1.40 for installations with box section, or 1.40 for installations with uncompacted filluncompacted fill

LRFD LRFD –– 12.11.2.2.112.11.2.2.1Standard Standard –– 16.6.4.216.6.4.2

Vertical Soil Load

0.81.21.6

2

VAFi

1 2 3 4 5 6 7 80

0.4

li

“Bedding and Fill Heights for Concrete Roadway PipeAnd Box Culverts” – C. Yoo, F. Parker, and J. Kang,Auburn University, June 2005

Bottom Reaction to VerticalBottom Reaction to Vertical Loads

Bottom Reaction to VerticalBottom Reaction to Vertical Loads

LRFD (C12.11.2.3)

“While typical designs assume a uniform “While typical designs assume a uniform pressure distribution across the bottom slab, pressure distribution across the bottom slab, p ,p ,a refined analysis that considers the actual a refined analysis that considers the actual soil stiffness under box sections will result soil stiffness under box sections will result in pressure distributions that reduce bottom in pressure distributions that reduce bottom slab shear and moment forces (McGrath et slab shear and moment forces (McGrath et ((al. 2004.”al. 2004.”

LRFD C12.11.2.3

“Such an analysis requires knowledge of in“Such an analysis requires knowledge of in--situ soil properties to select the appropriate situ soil properties to select the appropriate p p pp pp p pp pstiffness for the supporting soil. A refined stiffness for the supporting soil. A refined analysis taking this into account may be analysis taking this into account may be y g yy g ybeneficial when analyzing existing beneficial when analyzing existing culverts.”culverts.”

Horizontal Loads

Approaching Live LoadApproaching Live Load Earth LoadsEarth Loads Earth LoadsEarth Loads Fluid LoadsFluid Loads

Approaching Live Load

Lateral Live Load (Boussinesq)

Lateral Live Load

LRFD (3.11.6.2)LRFD (3.11.6.2)“The horizontal pressure“The horizontal pressure hh in ksf, on ain ksf, on a The horizontal pressure The horizontal pressure phph in ksf, on a in ksf, on a

wall resulting from a point load may be wall resulting from a point load may be taken as:”taken as:”taken as:taken as:

P 3ZX2 R (1 2)[ ]ph =PR2

3ZX2

R3

R (1 - 2)R + Z[ ]

Live Load Lateral Uniform Pressure

LRFD LRFD –– 3.11.6.4 (equivalent fluid load)3.11.6.4 (equivalent fluid load)H H << 5 ft 5 ft –– 4 ft4 ftH H << 10 ft 10 ft –– 3 ft3 ftHH << 20 ft20 ft –– 2 ft2 ftH H 20 ft 20 ft 2 ft2 ft

ΔΔpp = K = K γγss hheqeq

Lateral Uniform Live Load

“In general, LRFD produces greater live load surchargepressures than Standard for depths of fill of 5 ft or less and less pressure for greater depths In addition live loadless pressure for greater depths. In addition, live load surcharge pressures from AASHTO M 259 and M 273 are much greater than those from LRFD for depths of fill from 0 1 f d l h LRFD f fill h i h I0 to 1 ft and less than LRFD for greater fill heights. Inspite of the significant differences in live load surchargepressures, their impact on reinforcement areas is relatively p p yminor”

“Comparison of AASHTO Standard and LRFD Code Provisions for Buried Concrete Box C l t ” R R d & T M G th STP 1368Culverts” – R. Rund & T. McGrath, STP 1368, 2000, Concrete Pipe for the New Millenium

Lateral Earth Pressure

Lateral Earth Load - LRFD

3.11.5.5 3.11.5.5 –– Equivalent Fluid MethodEquivalent Fluid MethodLoose Sand or Gravel = 55 pcfLoose Sand or Gravel = 55 pcfLoose Sand or Gravel 55 pcfLoose Sand or Gravel 55 pcfDense Sand or Gravel = 45 pcfDense Sand or Gravel = 45 pcf

3 11 5 23 11 5 2 At R t PAt R t P 3.11.5.2 3.11.5.2 –– At Rest PressureAt Rest Pressurekkoo = 1= 1--sinsin

= 30= 30°°, k, koo = 0.5, press = 60 pcf= 0.5, press = 60 pcf

Lateral Earth Load (Min/Max)

3.4.13.4.1EHEHMaxMax = 1.35= 1.35MaxMaxEHEHMinMin = 0.90= 0.90

3.11.73.11.7 –– Reduction Due to Earth PressureReduction Due to Earth Pressure 3.11.7 3.11.7 Reduction Due to Earth PressureReduction Due to Earth Pressure“In lieu of more precise information, a 50 “In lieu of more precise information, a 50

percent reduction may be used, but needpercent reduction may be used, but needpercent reduction may be used, but need percent reduction may be used, but need not be combined with the minimum load not be combined with the minimum load factor specified in Table 3.4.1factor specified in Table 3.4.1--2.”2.”pp

Internal Fluid Pressure

γw = 62.4pcf

Other Loads

Construction LoadsConstruction Loads External Hydrostatic LoadsExternal Hydrostatic Loads External Hydrostatic LoadsExternal Hydrostatic Loads

Load FactorsLoad Factors

LRFD Design

Load Factors (LRFD)

Load Maximum Factor Minimum FactorD d (S ) 1 25 0 90Dead (Structure) 1.25 0.90Water 1.0 1.0Earth (vertical) 1.3 0.90Earth (horizontal) 1.35 0.90*Live 1.75 0

*50% Reduction in earth load may be used in lieu of thisL d f tLoad factor

Load Modifiers

LRFD C 1.3.2.1LRFD C 1.3.2.1“Ductility, redundancy, and operational“Ductility, redundancy, and operational Ductility, redundancy, and operational Ductility, redundancy, and operational

importance are significant aspects importance are significant aspects affecting the margin of safety of bridges.”affecting the margin of safety of bridges.”affecting the margin of safety of bridges.affecting the margin of safety of bridges.

Load Modifiers

Load Load Modifier for:Ductility Redundancy Operation*

Dead 1.0 1.0 1.0Water 1.0 1.0 1.0Earth 1 0 1 05 1 0Earth 1.0 1.05 1.0Live 1.0 1.0 1.0

*Load Modifier for Operation is dependent upon thespecifying agency and the importance of the functionspecifying agency and the importance of the functionand safety of the roadway.

Ultimate Load Combinations

Minimum Vertical and Maximum LateralMinimum Vertical and Maximum Lateral C = 0.9DC + 0.9EV + (1.05)1.35EH +C = 0.9DC + 0.9EV + (1.05)1.35EH + C 0.9DC + 0.9EV + (1.05)1.35EH + C 0.9DC + 0.9EV + (1.05)1.35EH +

1.75(1.2)LS1.75(1.2)LS

Maximum Vertical and Minimum LateralMaximum Vertical and Minimum Lateral A = 1.25DC + (1.05)1.3EV + (1.35)0.5EH + A = 1.25DC + (1.05)1.3EV + (1.35)0.5EH +

1.75(1.2)(1+IM)LL + 1.0WA1.75(1.2)(1+IM)LL + 1.0WA

Ultimate Load Combinations

Maximum Vertical and Maximum LateralMaximum Vertical and Maximum Lateral B = 1.25DC + (1.05)1.3EV + (1.05)1.35EH + B = 1.25DC + (1.05)1.3EV + (1.05)1.35EH +

1.75(1.2)(1+IM)LL + 1.75(1.2)LS1.75(1.2)(1+IM)LL + 1.75(1.2)LS

Typical Results (12 x 12 @ 20ft)0

20

0

Max Vert/

Min Horiz

40

60xi

xi

Min HorizMin Vert/

Max Horiz

80

xi

5 1054 1053 1052 1051 10501 105

100

120

MU12A i MU12C iMU12A i MU12C i

Design CapacityDesign Capacity

Design for:

FlexureFlexureSteel ReinforcementSteel ReinforcementSteel ReinforcementSteel ReinforcementConcrete CompressionConcrete Compression

C k C t lC k C t l Crack ControlCrack Control ShearShear FatigueFatigue (not required for box culverts per (not required for box culverts per

LRFD)LRFD)))

Phi Factors

Strength Reduction FactorsStrength Reduction Factorsff = 1.0= 1.0ff 1.0 1.0vv = 0.9= 0.9

LRFDLRFD 12 5 512 5 5 11LRFD LRFD –– 12.5.512.5.5--11Standard Standard –– 16.7.4.616.7.4.6

Flexure

Asig f d Nu g g f d 2 Nu 2 f d t 2 Mu

f

fy

E ti 12 10 4 2 4 1 F PiEquation 12.10.4.2.4a-1 – For Pipe

Section 5.7.2 – Assumptions for Strength and Extreme EventLimit States takes a broader view of flexural design

Flexure (Minimum Steel)Flexure (Minimum Steel)LRFD - 12.11.4.3.2: STD - 16.7.4.8

AsAsminmin = 0.002 b h= 0.002 b hb = 12 inch unit widthb = 12 inch unit widthb 12 inch unit widthb 12 inch unit widthh = thickness of member in inchesh = thickness of member in inches

LRFD (12 11 4 3 2)LRFD (12 11 4 3 2) LRFD (12.11.4.3.2)LRFD (12.11.4.3.2) Standard (16.7.4.8)Standard (16.7.4.8)

ACI 318-08ACI 318 08

Flexure (maximum steel)

For box culverts it is 75% of the steel area For box culverts it is 75% of the steel area for a balanced condition (steel will always for a balanced condition (steel will always ( y( yyield before concrete crushes)yield before concrete crushes)

Other concrete structures design forOther concrete structures design for Other concrete structures design for Other concrete structures design for concrete crushing with lower phi factorsconcrete crushing with lower phi factors

Tension Controlled - Ductile

Phi FactorsPhi graph related to strain.

St i 0 004047 0.75 s s N1s 0psi Thrust Strain = 0.004047Phi = 0.92

Crack Control (LRFD – 5.7.3.4)

s700 e

f2 dc

s fs

LRFD Concerns itself with steel spacingLRFD Concerns itself with steel spacing Standard Specification concerns itself withStandard Specification concerns itself with Standard Specification concerns itself with Standard Specification concerns itself with

stress in the steel (maximum of 0.6 fy?)stress in the steel (maximum of 0.6 fy?)

Service Load Stress

M N dh

fs

Ms Ns d2

s As j i d

Equation C12 11 3 1Equation C12.11.3-1

Factors affecting crack control

Exposure Conditions

SHEARSHEAR

ShearLRFD – 5.14.5.3: STD – 8.16.6.7LRFD 5.14.5.3: STD 8.16.6.7

Slabs under 2 feet or more of fill

V 0 0676 f'c 4 6As

Vu de

b d

Slabs under 2 feet or more of fill

Vc 0.0676 f c 4.6b de Mu

b de

Need not be taken less thanNeed not be taken less than

Vc 0.0948 f'c b d e

Equivalent to = 3

ShearLRFD 5 8 3 3 STD 8 16 6 2 1LRFD – 5.8.3.3: STD – 8.16.6.2.1Slabs with less than two feet of cover, and sidewalls

V 0 0316 f'c b d

and sidewalls

Vc 0.0316 f c bv dv

is based on the dimensions of the element and the strain in the steel

ShearLRFD 5 8 3 3 STD 8 16 6 2 1LRFD – 5.8.3.3: STD – 8.16.6.2.1Slabs with less than two feet of cover, and sidewalls

F ti ith ll d th l th 16 i hFor sections with an overall depth less than 16 inches, and no tension, can be assumed equal to 2

Top Slab

12X12 @20’12X12 @20’

Side Wall

12X12 @ 20’@

5.8.3 Method versus 5.14.5.3 Method8 X 8 Box

Wire ASSpacing (IN)

ASbd

p= ß 5.8.3

2 0.011 2.7 2 - 4LRFD 0.012 2.8 4 0 013 2 94 0.013 2.9N/A 0.015 3.0

Fatigue

STD – 8.16.8.3

ff 21 0.33 fmin 8rh

h

LRFD – 5 5 3 1LRFD 5.5.3.1

“Fatigue need not be investigated for concrete deck l b i lti i d li ti i f dslabs in multigirder applications or reinforced-

concrete box culverts.”

Distribution Steel

Distribution Steel

In bottom of top slab (LRFD 9.7.3.2)In bottom of top slab (LRFD 9.7.3.2)Percentage of main positive momentPercentage of main positive momentPercentage of main positive moment Percentage of main positive moment

reinforcement = 100/Sreinforcement = 100/S1/21/2

S = span in feetS = span in feetS = span in feetS = span in feetNeed not be more than 50 percentNeed not be more than 50 percent

In top of top slabIn top of top slabAsAs66 = 0.002 x Ag= 0.002 x Ag66 gg

Research Has HelpedResearch Has Helped

Load Transfer Across the JointsLoad Transfer Across the Joints

UTA Research on Shear in BoxUTA Research on Shear in Box Culverts

AASHTO LRFD Results

4.6.2.10.4 Precast Box Culverts For precast box culverts with top slabs For precast box culverts with top slabs

having span to thickness ratios (s/t) of 18 or less and segment lengths equal to or greaterless and segment lengths equal to or greater than 4 feet in length, shear transfer across the joint need not be provided.the joint need not be provided.

AASHTO LRFD Results

12.11.2.1 For cast in place box culverts, and for For cast in place box culverts, and for

precast box culverts with top slabs having span to thickness ratios (s/t) greater than 18span to thickness ratios (s/t) greater than 18 or segment lengths less than 4.0 ft., edge beams shall be provided as specified inbeams shall be provided as specified in Article 4.6.2.1.4

FatigueFatigue

UNO Fatigue Evaluation forUNO Fatigue Evaluation for Reinforced Concrete Box Culverts

Fatigue

LRFD 5 5 3 1LRFD – 5.5.3.1

“Fatigue need not be investigated for concrete deck slabs in multigirder applications or reinforced-concrete box culverts ”concrete box culverts.

ASTMs

Boxes for all depths

C 1433 Design CriteriaC 1433 Design Criteria

Reinforcement Tables

C 1577 Design CriteriaCriteria

Reinforcement Tables

C 1577 – One Table

C 1433 T T blC 1433- Two Tables

Assumptions in the Tables of C 1577

f`f`cc = 5,000= 5,000 ff = 65,000= 65,000 ffyy 65,000 65,000 Circumferential spacing is 4 inchesCircumferential spacing is 4 inches

T ffi ll l t thT ffi ll l t th Traffic parallel to the spanTraffic parallel to the spanOK for skews 15OK for skews 15°° or lessor less

Comparison of C 1577 versusComparison of C 1577 versus previous ASTM Standards 0 to 3 feet of cover has less steel overall0 to 3 feet of cover has less steel overall

Fatigue does not govern with C 1577Fatigue does not govern with C 1577 3 to 5 feet of cover has more steel overall3 to 5 feet of cover has more steel overall

1.15 live load distribution versus 1.75 live load 1.15 live load distribution versus 1.75 live load distribution in C 1433, and higher impact distribution in C 1433, and higher impact factors results in higher live load pressuresfactors results in higher live load pressures

At deeper fills C 1577 has less steel overallAt deeper fills C 1577 has less steel overall Crack control in C 1577 is more liberalCrack control in C 1577 is more liberal

The EndThis presentation can be downloaded at:This presentation can be downloaded at:

http://xfer.concretehttp://xfer.concrete--pipe.org/pipe.org/

Password:Password:“LRFDBOX”“LRFDBOX”

Lane Load

Applied Live loadsApplied Live loads

3 6 1 3 3 D i L d f D k D k3 6 1 3 3 D i L d f D k D k 3.6.1.3.3 Design Loads for Decks, Deck 3.6.1.3.3 Design Loads for Decks, Deck Systems, and the Top Slabs of Box Systems, and the Top Slabs of Box CulvertsCulvertsCulvertsCulvertsWhere the slab spans primarily in the Where the slab spans primarily in the

transverse direction, only the axles of transverse direction, only the axles of the design truck of Article 3.6.1.2.2 or the design truck of Article 3.6.1.2.2 or design tandem of Article 3.6.1.2.3 design tandem of Article 3.6.1.2.3 shall be applied to the deck slab of theshall be applied to the deck slab of theshall be applied to the deck slab of the shall be applied to the deck slab of the top of box culverts.top of box culverts.

Applied Live loadsApplied Live loads

3 6 1 3 3 Design Loads for Decks Deck3 6 1 3 3 Design Loads for Decks Deck 3.6.1.3.3 Design Loads for Decks, Deck 3.6.1.3.3 Design Loads for Decks, Deck Systems, and the Top Slabs of Box CulvertsSystems, and the Top Slabs of Box Culverts Where the slab spans primarily in the Where the slab spans primarily in the

longitudinal direction:longitudinal direction:longitudinal direction:longitudinal direction: For top slabs of box culverts of all spans and For top slabs of box culverts of all spans and

for all other cases, including slabfor all other cases, including slab--type type bridges where the span does not exceed 15 0bridges where the span does not exceed 15 0bridges where the span does not exceed 15.0 bridges where the span does not exceed 15.0 ft, only the axle loads of the design truck or ft, only the axle loads of the design truck or design tandem of Articles 3.6.1.2.2 and design tandem of Articles 3.6.1.2.2 and 3 6 1 2 3 respectively shall be applied3 6 1 2 3 respectively shall be applied3.6.1.2.3, respectively, shall be applied.3.6.1.2.3, respectively, shall be applied.

Lateral Uniform Live Load

LRFD (3.11.6.4)LRFD (3.11.6.4)“A live load surcharge shall be applied“A live load surcharge shall be applied A live load surcharge shall be applied A live load surcharge shall be applied

where vehicular load is expected to act on where vehicular load is expected to act on the surface of the backfill within athe surface of the backfill within athe surface of the backfill within a the surface of the backfill within a distance equal to onedistance equal to one--half the wall height half the wall height behind the back face of the wall.”behind the back face of the wall.”behind the back face of the wall.behind the back face of the wall.

Soil Load (Assumed)

VerticalVertical Pressures

Soil Pressures

Top Corner Bottom CornerBottom Corner

Soil PressuresSoil Pressures

Standards/Specifications for BoxStandards/Specifications for Box Culverts M 259 (C789)M 259 (C789) M 273 (C 850)M 273 (C 850) M 273 (C 850)M 273 (C 850) C1433 (Standard)C1433 (Standard)

C1577 (LRFD*)C1577 (LRFD*) C1577 (LRFD*)C1577 (LRFD*)

First Precast Box Culvert Standards

105

Standards C 789 C 789 –– “Standard Specification for Precast Reinforced “Standard Specification for Precast Reinforced pp

Concrete Box Sections for Culverts, Storm Drains, and Concrete Box Sections for Culverts, Storm Drains, and Sewers”Sewers” Originally Published in 1974Originally Published in 1974g yg y Adopted by AASHTO as M 259Adopted by AASHTO as M 259

C 850 C 850 –– “Standard Specification for Precast Reinforced “Standard Specification for Precast Reinforced Concrete Box Sections for Culverts, Storm Drains, andConcrete Box Sections for Culverts, Storm Drains, andConcrete Box Sections for Culverts, Storm Drains, and Concrete Box Sections for Culverts, Storm Drains, and Sewers with Less Than 2 ft of Cover Subjected to Sewers with Less Than 2 ft of Cover Subjected to Highway Loadings”Highway Loadings” Originally Published in 1976Originally Published in 1976g yg y Adopted by AASHTO as M 273Adopted by AASHTO as M 273

106“Structural Design of Precast Concrete Box Sections for Zero to Deep EarthBox Sections for Zero to Deep Earth Cover Conditions and Surface Wheel L d ”Loads” By F.J. Heger and K.N. LongBy F.J. Heger and K.N. Longy g gy g g Written in 1977Written in 1977 “The standard designs presented in ASTM “The standard designs presented in ASTM

S ifi ti C 789S ifi ti C 789 74 t d b74 t d bSpecification C 789Specification C 789--74 were generated by a 74 were generated by a computerized design method developed at computerized design method developed at Simpson Gumpertz & Heger Inc. (SHG) under Simpson Gumpertz & Heger Inc. (SHG) under

ACPA d ifi d bACPA d ifi d bcontract to ACPA, and were verified by a test contract to ACPA, and were verified by a test program carried out by ACPA with SGH program carried out by ACPA with SGH assistance.”assistance.”

ASTM C 1433107

“Standard Specification for Precast Reinforced“Standard Specification for Precast Reinforced Standard Specification for Precast Reinforced Standard Specification for Precast Reinforced Concrete Monolithic Box Sections for Concrete Monolithic Box Sections for Culverts, Storm Drains, and Sewers”Culverts, Storm Drains, and Sewers”, ,, , Originated in 1999Originated in 1999 Developed to more closely follow theDeveloped to more closely follow the Developed to more closely follow the Developed to more closely follow the

AASHTO SpecificationsAASHTO Specifications Combined shallow and deep fill heights in Combined shallow and deep fill heights in p gp g

one standardone standard ASTM C 789 and C 850 Discontinued in ASTM C 789 and C 850 Discontinued in

20002000

ASTM C 1577108

“Standard Specification for Precast“Standard Specification for Precast Standard Specification for Precast Standard Specification for Precast Reinforced Concrete Monolithic Box Reinforced Concrete Monolithic Box Sections for Culverts Storm Drains andSections for Culverts Storm Drains andSections for Culverts, Storm Drains, and Sections for Culverts, Storm Drains, and Sewers Designed According to Sewers Designed According to AASHTO LRFD”AASHTO LRFD”AASHTO LRFDAASHTO LRFDOriginated in 2005Originated in 2005