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CE 563 Airport Design
Reference: AC 150/5320-‐6E
Pavement design life used Correct surface distress Correct surface condition Damage from overloading Serve heavier aircraft
Assess existing pavement condition Thickness Condition Strength Subgrade soil classification Foundational strength
Subsurface drainage condition Repair severe distress
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Asphalt over existing flexible pavement Concrete over existing flexible pavement Asphalt over existing rigid pavement Concrete over existing rigid pavement
AC 150/5320-6E 9/30/2009!!
"#$$%"&!'"!(#$$)'*&+!,('-(!.-!,)%/&0&1.!-2!%!345!-(!677!-8&()%9:!.;&!-8&()%'+!".(#/.#(&!";-#)+!1-.!$&!/-1"'+&(&+!"%1+<'/;!/-1".(#/.'-1=!!
!FIGURE 4-1. TYPICAL OVERLAY PAVEMENTS
>?!
AC 150/5320-6E 9/30/2009!!
"#$$%"&!'"!(#$$)'*&+!,('-(!.-!,)%/&0&1.!-2!%!345!-(!677!-8&()%9:!.;&!-8&()%'+!".(#/.#(&!";-#)+!1-.!$&!/-1"'+&(&+!"%1+<'/;!/-1".(#/.'-1=!!
!FIGURE 4-1. TYPICAL OVERLAY PAVEMENTS
>?!
AC 150/5320-6E 9/30/2009!!
"#$$%"&!'"!(#$$)'*&+!,('-(!.-!,)%/&0&1.!-2!%!345!-(!677!-8&()%9:!.;&!-8&()%'+!".(#/.#(&!";-#)+!1-.!$&!/-1"'+&(&+!"%1+<'/;!/-1".(#/.'-1=!!
!FIGURE 4-1. TYPICAL OVERLAY PAVEMENTS
>?!
AC 150/5320-6E 9/30/2009!!
"#$$%"&!'"!(#$$)'*&+!,('-(!.-!,)%/&0&1.!-2!%!345!-(!677!-8&()%9:!.;&!-8&()%'+!".(#/.#(&!";-#)+!1-.!$&!/-1"'+&(&+!"%1+<'/;!/-1".(#/.'-1=!!
!FIGURE 4-1. TYPICAL OVERLAY PAVEMENTS
>?!
Base Course HMA
Subgrade
Compression
Tension
Determine thickness and moduli of existing pavement layers
Aircraft mixture Use FAARFIELD
Trial overlay thickness Program iterates until CDF of 1 is obtained Minimum overlay of 2 inches for asphalt overlay of existing flexible pavement
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Taxiway Asphalt surface, 4 inches P-‐209, 10 inches P-‐154, 6 inches Subgrade CBR = 10 Negligible frost action Aircraft mixture as shown
Find necessary asphalt overlay thickness
Aircraft Gross Weight, tons
Annual Departures
DC10-‐10 458,000 2,263 B747-‐200B 873,000 832 B777-‐200 ER 634,500 425
9/30/2009 AC 150/5320-6E!!!
c. FAARFIELD Overlay Design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
(1) S1+!G,N!5*3#&%+!E=$(%&'!12!8N,*+,.;!4%$N,Q%$!F&=$0$.+!(2) T1.-($+$!E=$(%&'!12!8N,*+,.;!4%$N,Q%$!F&=$0$.+!!(3) S1+!G,N!5*3#&%+!E=$(%&'!12!8N,*+,.;!6,;,)!F&=$0$.+!!(4) T1.-($+$!E=$(%&'!12!8N,*+,.;!6,;,)!F&=$0$.+!
404. OVERLAYS OF EXISTING FLEXIBLE PAVEMENTS>!"#$!)$*,;.!12!&.!1=$(%&'!21(!&.!$N,*+,.;!2%$N,Q%$!3&=$0$.+!,*!$**$.+,&%%'!+#$!*&0$!&*!)$*,;.,.;!&!.$<!3&=$0$.+>!"#$!$N,*+,.;!2%$N,Q%$!3&=$0$.+!,*!-#&(&-+$(,U$)!Q'!&**,;.,.;!+#$!&33(13(,&+$!+#,-@.$**$*!&.)!01)?%,!12!+#$!$N,*+,.;!%&'$(*>!5!A?&%,2,$)!$.;,.$$(!*#1?%)!Q$!-1.*?%+$)!+1!-#&(&-+$(,U$!+#$!$N,*+,.;!3&=$0$.+!%&'$(*>!
a. Hot Mix Overlay of an Existing Flexible Pavement.!5!+(,&%!+#,-@.$**!12!1=$(%&'!,*!*$%$-+$)!&.)!+#$!3(1;(&0!,+$(&+$*!?.+,%!&!T:4!12!K>C!,*!($&-#$)>!"#$!1=$(%&'!+#,-@.$**!($A?,($)!+1!&-#,$=$!&!T:4!12!K>C!,*!+#$!)$*,;.!+#,-@.$**>!!S1<$=$(D!+#$!0,.,0?0!#1+!0,N!1=$(%&'!12!&.!$N,*+,.;!2%$N,Q%$!3&=$0$.+!,*!B!,.-#$*!MVC!00P>!
!FIGURE 4-2. DESIGN EXAMPLE OF FLEXIBLE OVERLAY ON EXISTING FLEXIBLE PAVEMENT
(1) Example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
VL!
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Taxiway Asphalt surface, 4 inches P-‐209, 12 inches Subgrade CBR = 10 (k = 141 pci) Negligible frost action Aircraft mixture as shown
Find necessary PCC overlay thickness
9/30/2009 AC 150/5320-6E!!!
!FIGURE 4-3. DESIGN EXAMPLE OF RIGID OVERLAY ON EXISTING FLEXIBLE PAVEMENT
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
a. Structural Condition Index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
TABLE 4-1. RIGID PAVEMENT DISTRESS TYPES USED TO CALCULATE THE STRUCTURAL CONDITION INDEX, SCI
='&2-$&&! A$,$-'20!Q$,$.!B*-)$-!W-$/X!! Q*8?!H$%'74?!Y'(#!Q*)('27%')/.K"-/)&,$-&$K='/(*)/.!B-/5X')(! Q*8?!H$%'74?!Y'(#!A#/22$-$%!A./6! Q*8?!H$%'74?!Y'(#!A#-')X/($!B-/5X&!;5-/5X')(!3/-2'/.!8'%2#!*+!&./6>/! Q*8!A3/..')(Z[*')2! Q*8?!H$%'74?!Y'(#!A3/..')(ZB*-)$-! Q*8?!H$%'74?!Y'(#!
!/!\&$%!*).0!2*!%$&5-'6$!/!.*/%:')%75$%!5-/5X!2#/2!$12$)%&!*).0!3/-2!*+!2#$!8/0!/5-*&&!/!&./69!!"#$!ABC!%*$&!)*2!')5.7%$!5*),$)2'*)/.!&#-')X/($!5-/5X&!%7$!2*!57-')(!*-!*2#$-!)*)!.*/%:-$./2$%!3-*6.$4&9!
F)!ABC!*+!IS!'&!2#$!EFF!%$+')'2'*)!*+!&2-7527-/.!+/'.7-$!*+!/!-'('%!3/,$4$)2?!/)%!'&!5*)&'&2$)2!8'2#!TS!3$-5$)2!*+!&./6&!')!2#$!2-/++'5!/-$/!$1#'6'2')(!/!&2-7527-/.!5-/5X9!"#$!ABC!/..*8&!/!4*-$!3-$5'&$!/)%!-$3-*%75'6.$!-/2')(!*+!/!3/,$4$)2R&!5*)%'2'*)!2#/)!2#$!3-$,'*7&!EFF!5*)%'2'*)!+/52*-!-/2')(&?!Cb!/)%!Cr9!
]L!
Determine condition of existing rigid pavement Structural condition index (SCI) Cumulative damage factor used (CDFU)
Determine thickness and moduli of existing pavement layers
Aircraft mixture Use FAARFIELD
Trial overlay thickness
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Derived from pavement condition index (PCI) Uses only the structural components of PCI PCI has 15 different distress types SCI uses 6 of the 15
FAA defines rigid structural failure at SCI = 80 50 percent of slabs exhibit structural crack
Distress Severity Level
Corner break Low, Medium, High Longitudinal/transverse/diagonal cracking
Low, Medium, High
Shattered slab Low, Medium, High Shrinkage cracks Low Spalling-‐joint Low, Medium, High Spalling-‐corner Low, Medium, High
!"#=!""!$" % #&'$!
($)
'(%
(=!
*(
#'=!
+,
#
a = adjustment factor ms = total number of distress types related to
pavement structural failure nj = total number of severity levels for the ith
distress f(Ti, Sj, Dij) = deduct value for distress type Ti, at the
severity level Sj, existing at density Dij
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When SCI = 100, no visible distresses contributing to reduction in SCI
Use the CDFU Defines existing pavement life that has been used up to the time of overlay
CDFU = 100, existing pavement life has been used
LU = number of years of operation of the existing pavement until overlay
LD = design life of the existing pavement in years
!"#$%&$
'()*&"
++,-./+&$0'()*&
"
!"#$%1+++++++++++++++,-./+&$2'()*&
"
FAARFIELD will calculate CDFU Enter the structure based on original design assumptions
Enter estimated traffic applied to the pavement Set design life to number of years existing pavement has been in operation
Run life CDFU is displayed
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Taxiway PCC, 15.3 inches P-‐306 Econocrete, 6 inches P-‐209, 6 inches Subgrade CBR = 10 (k = 141 pci) Negligible frost action Aircraft mixture as shown, 12 year in-‐service life
Find CDFU
Aircraft Gross Weight, tons
Annual Departures
DC10-‐10 458,000 1,200 B747-‐200B 873,000 300 B777-‐200 ER 634,500 200
9/30/2009 AC 150/5320-6E!!
!
"#$!%&''(!&)*#)+,+!-#)-$,.,!#/,$'0(1!.2,!3#+&'&4!#%!.2,!*04,!50/,3,).!/0$6,4!04!0!%&)-.6#)!#%!.2,!789!#%!.2,!*04,!
50/,3,).!:2,)!.2,!789!64!',44!.20)!;<<=!>264!-#35&.0.6#)!64!+#),!0&.#30.6-0''(!:6.26)!"??@"9ABC=!>2,!,D&0.6#)4!
%#$!.2,!3#+&'&4!$,+&-.6#)!04!0!%&)-.6#)!#%!.2,!789!0$,!E6/,)!6)!@,5#$.!F#=!CG>H"??HIJHKLM;N=!
Example=!>2,!%#''#:6)E!4.,54!6''&4.$0.,!.2,!5$#-,+&$,!%#$!-0'-&'0.6)E!8C"OP!
!
FIGURE 4-4. CDFU COMPUTATION USING FAARFIELD
(1) 7,.!&5!.2,!4.$&-.&$,!*04,+!#)!.2,!#$6E6)0'!+,46E)!044&35.6#)4=!?44&3,!0)!,Q64.6)E!.0Q6:0(!
50/,3,).!-#35#4,+!#%P!;R=S!6)-2!TSKK!33U!.26-V!I88!4&$%0-,!-#&$4,W!X!6)-2!T;RY!33U!.26-V!4.0*6'6Z,+!*04,!-#&$4,1!
9.,3!IHS<X!A-#)#-$,.,W!X!6)-2!T;RY!33U!.26-V!4&**04,!-#&$4,1!9.,3!IHY<N!8$&42,+!?EE$,E0.,=!>2,!4&*E$0+,!VH/0'&,!64!
;[;!5-6!TSK=[!JFM3SU1!,D&6/0',).!.#!0)!EH3#+&'&4!#%!;R1<<<!546!T;<S=[!JI0U=!>2,!,Q64.6)E!50/,3,).!:04!+,46E),+!.#!0--#33#+0.,!.2,!%#''#:6)E!06$5'0),!36QP!YYXS!0))&0'!+,50$.&$,4!#%!.2,!C8;<H;<!TE$#44!.0Q6!:,6E2.![RK1<<<!'*4!TY<L!
L<<!VEUU1!KSY!0))&0'!+,50$.&$,4!#%!.2,!\L[LHY<<\!8#3*6!J6Q,+!TE$#44!.0Q6!:,6E2.!KSS1<<<!'*4!TSLL!K<<!VEUU1!0)+![YR!
0))&0'!+,50$.&$,4!#%!.2,!\LLLHY<<!A@!TE$#44!.0Q6!:,6E2.!XS[1R<<!'*4!TYKL!K<<!VEUU=!>2,!+,46E)!'6%,!:04!Y<!(,0$4=!
(2) A4.630.,!.2,!.$0%%6-!055'6,+!.#!.2,!50/,3,).!0)+!,).,$!6.!6).#!.2,!06$5'0),!+,46E)!'64.=!?44&3,!
.20.!.2,!0))&0'!.$0%%6-!',/,'4!0-.&0''(!055'6,+!.#!.2,!50/,3,).!:,$,P!;Y<<!0))&0'!+,50$.&$,4!#%!.2,!C8;<H;<1!S<<!0))&0'!
+,50$.&$,4!#%!.2,!\L[L1!0)+!Y<<!0))&0'!+,50$.&$,4!#%!.2,!\LLL=!
(3) 7,.!]C,46E)!B6%,^!.#!.2,!)&3*,$!#%!(,0$4!.2,!50/,3,).!:6''!20/,!*,,)!6)!#5,$0.6#)!&5!.#!.2,!
.63,!#%!.2,!#/,$'0(=!?44&3,!.20.!0.!.2,!.63,!#%!.2,!#/,$'0(!.2,!.0Q6:0(!:6''!20/,!*,,)!6)!#5,$0.6#)!%#$!;Y!(,0$4=!9)!.2,!
]7.$&-.&$,^!:6)+#:1!-'6-V!#)!]C,46E)!B6%,^!0)+!-20)E,!.#!;Y!(,0$4=!"6E&$,![H[!42#:4!.20.!.2,!+,46E)!'6%,!204!*,,)!
0+_&4.,+!.#!;Y!(,0$4=!
(4) @&)!B6%,=!>2,!-0'-&'0.,+!5,$-,).!8C"O!:6''!055,0$!#)!.2,!7.$&-.&$,!4-$,,)1!0.!.2,!'#:,$!',%.!
#%!.2,!50/,3,).!4,-.6#)=!T7,,!%6E&$,![H[U=!
"#$!.2,!0*#/,!-04,1!"??@"9ABC!-0'-&'0.,4!5,$-,).!8C"O!,D&0'!.#![<=<K=!"#$!#/,$'0(!+,46E)1!.2,!/0'&,!8C"O!`![<!
5,$-,).!:#&'+!*,!&4,+=!
XS!
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SCI less than 100 Existing pavement has structural distress FAARFIELD assumes initial overlay thickness and iterates until reaching 20-‐year design life
SCI equals 100 No structural distress CDFU is needed FAARFIELD assumes initial overlay thickness and iterates until reaching 20-‐year design life
Taxiway PCC, 14 inches P-‐304 CTB, 6 inches P-‐209, 6 inches Subgrade CBR = 10 (k = 141 pci) Negligible frost action Aircraft mixture as shown
Find required asphalt thickness
Aircraft Gross Weight, tons
Annual Departures
DC10-‐10 458,000 2,263 B747-‐200B 873,000 832 B777-‐200 ER 634,500 425
4/14/14
9
AC 150/5320-6E 9/30/2009!!
"#$%&'!(')**#+!,&-&,./!%&)-#&'!)#'0,)1&./!2'!)!,21$&'!34&.#$1!,#*&5!6#,,!'&.7,(!#1!)!%#$%&'!+),+7,)(&4!-),7&!2*!89:;<=!>1!(%#.!&?)@0,&/!#*!(%&!%#$%&'!(')**#+!,&-&,.!7.&4!#1!(%&!2'#$#1),!4&.#$1!%)4!)+(7),,A!B&&1!)00,#&4!(2!(%&!0)-&@&1(/!(%&!0&'+&1(!9:;<!+2@07(&4!BA!;CCD;>EF:!627,4!#1+'&).&!(2!GH=IJ=!!
c. Hot Mix Asphalt Overlays of Existing Rigid Pavements.!K%&!4&.#$1!0'2+&..!*2'!%2(!@#?!2-&',)A.!2*!'#$#4!0)-&@&1(.!+21.#4&'.!(62!+214#(#21.!*2'!(%&!&?#.(#1$!'#$#4!0)-&@&1(!(2!B&!2-&',)#4L!MJN!O9>!2*!(%&!&?#.(#1$!0)-&@&1(!,&..!(%)1!JPPQ!MIN!O9>!&R7),!(2!JPP=!!
(1) Structural Condition Index Less Than 100. K%&!@2.(!,#S&,A!.#(7)(#21!#.!21&!#1!6%#+%!(%&!&?#.(#1$!0)-&@&1(!#.!&?%#B#(#1$!.2@&!.('7+(7'),!4#.('&../!#=&=/!(%&!O9>!#.!,&..!(%)1!JPP=!>*!(%&!O9>!#.!,&..!(%)1!JPP/!(%&!2-&',)A!)14!B).&!0)-&@&1(!4&(&'#2')(&!)(!)!$#-&1!')(&!71(#,!*)#,7'&!#.!'&)+%&4=!;CCD;>EF:!)..7@&.!)1!#1#(#),!2-&',)A!(%#+S1&..!)14!#(&')(&.!21!(%&!2-&',)A!(%#+S1&..!71(#,!)!IPTA&)'!,#*&!#.!0'&4#+(&4=!C!IPTA&)'!0'&4#+(&4!,#*&!.)(#.*#&.!(%&!4&.#$1!'&R7#'&@&1(.=!
(i) Example. K2!#,,7.(')(&!(%&!0'2+&47'&!2*!4&.#$1#1$!)!"UC!2-&',)A/!)..7@&!)1!&?#.(#1$!()?#6)A!0)-&@&1(!+2@02.&4!2*!(%&!*2,,26#1$!.&+(#21L!(%&!.7B$')4&!k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
[TVPJ!C9!2-&',)A!! ! V=I_!#1+%&.!MJP_!@@N![99!O7'*)+&! ! ! JV!#1+%&.!MWZ\!@@N![TWPV!O()B#,#]&4!B).&! ! !!!\!#1+%&.!MJZI!@@N![TIP_!O7BB).&!! ! !!!\!#1+%&.!MJZI!@@N!
K2(),!0)-&@&1(!(%#+S1&..! WP=I_!#1+%&.!MHHP!@@N!
K%&!'&R7#'&4!2-&',)A!(%#+S1&..!#.!V=I_!#1+%&.!MJP_!@@N!)14!6#,,!B&!'2714&4!70!(2!V=Z!#1+%&.!MJJV!@@N!MO&&!*#$7'&!VTZN=!K%&!(%#+S1&..!$&1&')(&4!BA!;CCD;>EF:!42&.!12(!)44'&..!'&*,&+(#21!+')+S#1$=!C44#(#21),!$7#4)1+&!21!'&*,&+(#21!+')+S#1$!#.!0'2-#4&4!#1!0)')$')0%!VPZ+MZN=!
!FIGURE 4-5. DESIGN EXAMPLE OF FLEXIBLE OVERLAY ON EXISTING RIGID PAVEMENT WITH
SCI 70
\V!
Taxiway PCC, 14 inches P-‐304 CTB, 6 inches P-‐209, 6 inches Subgrade CBR = 10 (k = 141 pci) Negligible frost action Aircraft mixture as shown CDFU = 50 percent
Find required asphalt thickness
9/30/2009 AC 150/5320-6E!!!
(2) Structural Condition Index Equal to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
(i) Example.!L3!&::9'(7+($!(/$!*73=$<97$!34!<$'&)#&#)!+#!MN"!3,$7:+;@!+''9-$!+#!$%&'(&#)!7&)&<!(+%&.+;!*+,$-$#(>!L/$!$%&'(&#)!*+,$-$#(!'$=(&3#!+#<!+&7*:+#$!-&%!&'!(/$!'+-$!+'!(/$!$%+-*:$!&#!G5H!+?3,$>!B73'(!+=(&3#!&'!#$):&)&?:$>!L/$!012!&'!566!G(/$7$!+7$!#3!,&'&?:$!'(79=(97+:!<&'(7$''$'H@!?9(!?+'$<!3#!+#!+#+:;'&'!34!(/$!(7+44&=!(/+(!/+'!?$$#!+**:&$<!?;!(/$!*+,$-$#(!(3!<+($@!(/$!O!1ABC!&'!$'(&-+($<!(3!?$!P6!*$7=$#(>!L/$!4:$%&?:$!*+,$-$#(!3,$7:+;!7$89&7$<!?+'$<!3#!B""DB2EFA!437!(/$'$!=3#<&(&3#'!&'Q!
RKS65!"1!3,$7:+;!! ! !!!!T>JP!&#=/$'!GUT!--H!R11!0974+=$! ! ! !!5S>66!&#=/$'!GTPV!--H!RKT6S!0(+?&:&W$<!?+'$! ! !!!!V>66!&#=/$'!G5PJ!--H!RKJ6X!09??+'$!! ! !!!!V>66!&#=/$'!G5PJ!--H!
L3(+:!*+,$-$#(!(/&=I#$''! !!JX>JP!&#=/$'!GYST!--H!
L/$!7$89&7$<!3,$7:+;!(/&=I#$''!G+'!'/3.#!&#!4&)97$!SKVH!&'!T>JP!&#=/$'!GUT!--H@!./&=/!.&::!?$!739#<$<!9*!(3!T>P!&#=/$'!GUX!--H>!L/$!7$89&7$<!3,$7:+;!(/&=I#$''!&'!5!&#=/!GJP>S!--H!:$''!(/+#!(/$!$%+-*:$!&#!G5H@!7$4:$=(&#)!(/$!4+=(!(/+(!(/$!R11!&'!&#!?$(($7!=3#<&(&3#>!
!FIGURE 4-6. DESIGN EXAMPLE OF FLEXIBLE OVERLAY ON EXISTING RIGID PAVEMENT WITH
SCI 100
(3) Previously Overlaid Rigid Pavement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
(4) Limitations.!B37!/3(!-&%!+'*/+:(!3,$7:+;!(/&=I#$''@!(/$!B""DB2EFA!*73)7+-!+''9-$'!(/$!$%&'(&#)!7&)&<!*+,$-$#(!.&::!'9**37(!:3+<!(/739)/!4:$%97+:!+=(&3#>!"'!(/$!3,$7:+;!(/&=I#$''!?$=3-$'!)7$+($7@!+(!'3-$!*3&#(!(/$!$%&'(&#)!7&)&<!*+,$-$#(!.&::!($#<!(3!+=(!-37$!:&I$!+!/&)/!89+:&(;!?+'$!-+($7&+:>!"'!(/$!3,$7:+;!(/&=I#$''!+**73+=/$'!(/$!(/&=I#$''!34!(/$!7&)&<!*+,$-$#(@!&(!-+;!?$!-37$!$=3#3-&=+:!(3!(7$+(!(/$!<$'&)#!+'!+!#$.!4:$%&?:$!
VP!
4/14/14
10
PCC
Load-‐induced movement
HMA
Reflection crack
Climate-‐induced movement
PCC overlay is intentionally not bonded to existing PCC surface
Typical for badly cracked pavements Thin layer of asphalt mixture used as bond breaker Determine SCI of existing pavement Determine thickness and moduli of existing pavement layers
Aircraft mix Use FAARFIELD
Trial overlay thickness
Taxiway Debonding layer, 1 inch PCC, 14 inches P-‐304 CTB, 6 inches P-‐209, 6 inches Subgrade CBR = 10 (k = 141 pci) Negligible frost action Aircraft mixture as shown SCI = 40 percent
4/14/14
11
9/30/2009 AC 150/5320-6E!!
!
(1) Fully Unbonded Concrete Overlay.!"#!$#%&#'('!)&#)*(+(!&,(*-./!&0!.#!(123+2#4!*242'!5.,(6(#+!23!&#(!2#!782)8!3+(53!.*(!+.9(#!+&!2#+(#+2&#.--/!(-262#.+(!%&#'2#4!%(+7((#!+8(!&,(*-./!.#'!(123+2#4!5.,(6(#+:!
;&66&#-/<!+8(!%&#'!23!%*&9(#!%/!.55-/2#4!.!+82#!8&+!621!-./(*!+&!+8(!(123+2#4!*242'!5.,(6(#+:!=8(!2#+(*0.)(!0*2)+2&#!
)&(002)2(#+!%(+7((#!+8(!&,(*-./!.#'!(123+2#4!5.,(6(#+!23!3(+!+&!*(0-()+!.#!$#%&#'('!)&#'2+2&#:!=8(!2#+(*0.)(!)&(002)2(#+!
23!021('!.#'!).##&+!%(!)8.#4('!%/!+8(!$3(*:!"3!72+8!8&+!621!.358.-+!&,(*-./3<!.#!>;?!23!*(@$2*('!+&!'(3)*2%(!+8(!
)&#'2+2&#!&0!+8(!(123+2#4!5.,(6(#+:!"!+*2.-!&,(*-./!+82)9#(33!23!2#5$+!.#'!A""BA?CDE!2+(*.+(3!$#+2-!.!FGH/(.*!3(*,2)(!
-20(!23!5*('2)+(':!=8(!+82)9#(33!+8.+!/2(-'3!.!FGH/(.*!3(*,2)(!-20(!23!+8(!'(324#!+82)9#(33:!I&7(,(*<!+8(!62#26$6!
+82)9#(33!0&*!.!0$--/!$#%&#'('!)&#)*(+(!&,(*-./!23!J!2#)8(3!KLMG!66N:!!
(i) Example:!=&!2--$3+*.+(!+8(!5*&)('$*(!&0!'(324#2#4!.#!$#%&#'('!)&#)*(+(!&,(*-./<!.33$6(!.#!(123+2#4!+.127./!5.,(6(#+!)&65&3('!&0!+8(!0&--&72#4!3()+2&#O!>;?!23!PG!0&*!+8(!(123+2#4!Q;;!3$*0.)(<!+8(!
3$%4*.'(!9H,.-$(!23!LPL!5)2!KMR:P!STU6MN<!)&**(35&#'2#4!+&!.#!EH6&'$-$3!&0!LJ<GGG!532!KLGM:PF!SQ.N<!+8(!(123+2#4!Q;;!3$*0.)(!)&$*3(!23!LP!2#)8(3!KLGF!66N!+82)9<!+8(!%.3(!)&$*3(!23!V!2#)8(3!KMGJ!66N!+82)9<!.#'!+8(!3$%%.3(!)&$*3(!23!V!
2#)8(3!KLJF!66N:!A*&3+!.)+2&#!23!#(4-242%-(:!"33$6(!+8(!(123+2#4!5.,(6(#+!23!+&!%(!3+*(#4+8(#('!+&!.))&66&'.+(!+8(!
0&--&72#4!.2*5-.#(!621O!E;LGHLG!7(2482#4!PJR<GGG!5&$#'3!KFGW!WPJ!94N!.+!.#!.##$.-!'(5.*+$*(!-(,(-!&0!F<FVM<!XWPWH
FGGX!;&6%2!S21('!7(2482#4!RWM<GGG!5&$#'3!KMYJ!YRV!94N!.+!.#!.##$.-!'(5.*+$*(!-(,(-!&0!RMF<!.#'!XWWWHFGG!CB!
7(2482#4!VMP<JGG!5&$#'3!KFGW!RGP!94N!.+!.#!.##$.-!'(5.*+$*(!-(,(-!&0!PFJ:!"33$6(!+8.+!+8(!Q;;!3+*(#4+8!23!WGG!532!0&*!
%&+8!+8(!&,(*-./!.#'!+8(!(123+2#4!)&#)*(+(:!=8(!&,(*-./!3+*$)+$*(!)&65$+('!%/!A""BA?CDE!0&*!+8(3(!)&#'2+2!23Z!
Q;;!$#%&#'('!&,(*-./! ! LM:JF!2#)8(3!KMPM!66N!
E(%&#'2#4!-./(*! ! L:GG!2#)8(3!KFJ!66N[!
Q;;!>$*0.)(! ! ! LP!2#)8(3!KMJV!66N!
QHMGP!>+.%2-2\('!%.3(! ! !!V!2#)8(3!KLJF!66N!
QHFGY!>$%%.3(!! ! !!V!2#)8(3!KLJF!66N!
=&+.-!5.,(6(#+!+82)9#(33! MY:JF!2#)8(3!KL!GGP!66N!
[T&+(O!A""BA?CDE!'&(3!#&+!2#)-$'(!+8(!'(%&#'2#4!-./(*!2#!+82)9#(33!).-)$-.+2:!
!
FIGURE 4-7. DESIGN EXAMPLE OF RIGID OVERLAY ON EXISTING FULLY UNBONDED RIGID PAVEMENT
A24$*(!PHW!38&73!+8(!*(@$2*('!&,(*-./!+82)9#(33!23!LM:JF!2#)8(3!KMPM!66N<!782)8!72--!%(!*&$#'('!+&!+8(!#(.*(3+!G:J!
2#)8(3<!&*!LM:J!2#)8(3!KMPM!66N:!
(2) Bonded Concrete Overlays. ;&#)*(+(!&,(*-./3!%&#'('!+&!(123+2#4!*242'!5.,(6(#+3!.*(!3&6(+26(3!$3('!$#'(*!)(*+.2#!)&#'2+2:!X/!%&#'2#4!+8(!)&#)*(+(!&,(*-./!+&!+8(!(123+2#4!*242'!5.,(6(#+!+8(!#(7!
VW!
PCC overlay is bonded to existing PCC surface Typical for pavements in good to excellent condition Grout used to bond pavements Bonded pavement act as monolithic slab Determine thickness and moduli of existing pavement layers
Aircraft mix Use FAARFIELD
Design as new rigid pavement Existing PCC flexural strength
!"#!$!
%
hc = PCC overlay thickness h = Required slab thickness he = Existing pavement thickness
4/14/14
12
Asphalt over rubblized PCC Similar to an asphalt over flexible pavement overlay design
Concrete over rubblized PCC Similar to design of a new PCC pavement
FAARFIELD can accept a rubblized PCC layer It becomes very important to determine the correct modulus value for the rubblized PCC
Slab thickness, inches Modulus, ksi 6-‐8 100-‐135 8-‐14 135-‐235 >14 235-‐400