aashto rcd

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Standard Specifications for Highway Bridges 17th Edition – 2002 Adopted and Published by the American Association of State Highway and Transportation Officials 444 North Capitol Street, N.W., Suite 249 Washington, D.C. 20001 Section 8 - REINFORCED CONCRETE 8.16 Strenght Design Method (Load Factor Design) 8.16.1.2.2 The strength-reduction factors, φ, shall be as follows: (a) Flexure 0.9 (b) Shear 0.85 (c) Axial compression with: Spirals 0.75 Ties 0.7 (d) Bearing on concrete0.7 but shall not be taken less than 0.65 for f'c ≤ 28 Mpa for f'c ≥ 28Mpa 8.16.3.2.2 The balanced reinforcement ratio, ρb, ρ_ =(0.85 β1 _ 600)/( _ (600+ _ )) β_1=0.8 5 β_1=0.85 −0.05/7( ^ −28) ρ_ =0.75 ρ_

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Reinforcement design using AASHTO standards

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Standard Specifcations for Highway Bridges17th Edition 2002Adopted and Published by theAmerican Association of State Highway and ransportation !"cials### $orth %apitol Street& $'('& Suite 2#)(ashington& *'%' 20001Section + , -E.$/!-%E* %!$%-EE8.16 Strenght Design Method (Load Factor Design)+'10'1'2'2 he strength,reduction factors& 1& shall beas follows23a4 /le5ure 0')3b4 Shear 0'+63c4 A5ial compression with2Spirals 0'76ies 0'73d4 7earing on concrete 0'7 but shall not be ta8en less than 0'06for f9c : 2+ ;pafor f9c < 2+;pa+'10'='2'2 he balanced reinforcement ratio& >b&> ?30'+6@1 _ A B0004C _ (_3000D _44@E1?0'+6@E1?0'+6 F0'06C7 GA (F2+4>E ?0'76> _Dee!op"ent of Defor"ed Bars in #ensionfor =0mm bar and smallershould be multiplied by applicable factors 3not stated here4Dee!op"ent of Defor"ed Bars in $o"pressionshould be multiplied by applicable factors 3not stated here4Dee!op"ent of Shear %einforce"entDee!op"ent of B&nd!ed Barshe deHelopment length of indiHidual bars within a bundle& in tension or compression& shall be that forthe indiHidual bar& increased by 20I for a three,bar bundle& and ==I for a four,bar bundle'Dee!op"ent of Standard Hoo's in #ension/or bars with fy eJual to #16 ;pa/or bars with fy other than #16 ;Pashould be multiplied by applicable factors 3not stated here4Dee!op"ent of Standard Hoo's in $o"pressionHoo8s shall not be considered eKectiHe in deHeloping bars in compression'Sp!ices of Defor"ed Bars in #ensionfy2 #16 ;paf9c2 2+ ;pa+ =00'000*iameter mmLdM mm ?30'0 4CN3 _ 2_ _GA 4 0'0 _ 6_ _ =0 0 ? _ (_ _4C3#N3 GA 44 0'0# _ _ _ ?310 4CN3 _ 0_GA 4_ 8_160 ?310 4CN3 _ 0_GA 4C#16__ 16 8_ 010 =00'00012 =00'00010 =)+'#0020 #)+'00026 70)')012+ )06'+#0=2 1201'606=0 16)0'6)2he deHelopment length of indiHidual bars within a bundle& in tension or compression& shall be that for