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TRANSCRIPT
PERFORMANCE BASED DESIGN METHOD AND APPLIED TECHNOLOGY FOR VERIFYING THE REQUIRED PERFORMANCE OF NEWLY DEVELOPED BRIDGES
*
Masatsugu NAGAI
ABSTRACT Performance based design method (PBD) and limit state design method (LSD) are explained, and for verifying the required performance, load resistance factor design method (LFRD) and partial factor design method (PFD) follow. In addition, allowable stress design method (ASD) is also explained. It is presented, in current steel bridge design practice, that outcome from the above different design methods is minor except for reducing the value of partial factor. However, for enhancing reliability and competitiveness of steel and hybrid bridges, importance of shift to PBD is emphasized. Finally, for verifying required performance of newly developed hybrid bridges, applied technology such as 3D-FEA and experiments are introduced. KEYWORDS : FEA
Design method, Performance verification method, FEA, experiments
(Allowable Stress Design Method : ASD)1), 2) (
) ( = 1.7) H141)( )
H24 2)
(AASHTO LRFD) (EC)(LRFD)
(PFD) ASD
第16回 鋼構造と橋に関するシンポジウム論文報告集（2013年8月） 土木学会
- 1 -
( )
3)
[ (2.2)]
( ) (ultimate or strength limit state) (serviceability limit
state) (fatigue limit state)EC
AASHTO LRFD 4)
(Load Resistance Factor Design Method, LRFD)
AASHTO LRFD
i i i n rQ R R� � � � �� (2.1)
Qi Rn Rr �i
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�i (�D : ductility) (�R : redundancy) (�I : operational importance) �
AASHTO ASD 1970 (LFD)
2012 LRFD LRFD [ ]�
LRFD
EC5)
6) 3)
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iy m b
S FR f� �
�� �
� (2.2)
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AASHRO LRFD
1), 2) 40
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(2.3) fcr
4 ( ) (fcr) (fy) ( 1.0)�c �b Ru, Rs ( ) ( )
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y Ef f ) fcr 1.7 (fa)
(fy) 1.7SM570 ( (fy) / (fB) )
1.77
� �cr y uf h f f �� � �� (2.4)
� e y uf h f �� �� (2.5)
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fy fE
0
0.5
1
1.5
0 0.5 1 1.5
fcr/ fy = 1/�2(R2)
� c , � b , Ru, Rc =
� c , � b , Ru, Rc
fcr /fy
( � c )( � b )
( Ru )( Rc )
fy fE
2 fe (Von Mieses) x-y 2
(fx, fy, �xy) ( 2 2 23e x x y y xyf f f f f � � � � )
10%
1.7 ( )
(h)1.7 AASHTO LRFD ASD
(h)
ASD ?? ?
?
LSD LRFD
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1980 BS(British Standard) LSD(Freeman Fox Dr. Brown)
30 LSD
(2.3)
LSD ( )
I BS
( ) () LSD
( )LSD
LRFDLSD LSD LRFD
(2.2)
(S) (R) (F) (S)(Finite Element Analysis, FEA)
FEA( )
FEA
2FEA
7) ( )
3D-FEA ( )( )
3D-FEA
(R)AASHTO LRFD, EC 8)
9) ( )
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(2.2) FEA(S) (R)
(2.2) (�m) 1.01.0 h = 1.0
� � i a f b S F R� � � � � � (3.1)
� i a f b crf f� � � � � � (3.2)
4 (2.3) 1.7
(code calibration)
??
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( /1.15)
( )
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1.7
AASHTO LRFD (3.3),(3.4)
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(3.4)
- 6 -
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(fy) ( )
[ + ]
a) (MP) b) ( )
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I (MP) (1.3 1.5)My 1.3My AASHTO LRFDEC 0.9MP
(3.4) (3.8)
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(3.3)(3.9) (3.9)
ASD (2.3)
1.7
AASHTO LRFD, EC
2
FEAASD
ASD
ASD
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AASHTO LRFD EC ( )10 AASHTO
LRFD AASHTO LRFD AASHTO LRFD
ASD
ASD (f) ( )(f1) 2 (f2)
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2 (f2) 21
1 ??
1), 2) 8) ()
( )
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(Q)
� �min , 1.7y cr yQ h Q Q Q� � �� (4.3)
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1
1 E sf f ��� (4.5)
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1 ( )3D-FEA pay
- 8 -
LSD (LSD )
()
( )
I
1 1
1
1.71
( ) 1
()
1
1
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11)
1
( )
2.5( )1), 2)
PC 1.71.7
2.2( 1.7 )
1.7
2.5 1), 2) 1
3D-FEA
2 I a)
- 10 -
=3.0 ( 1.5 ) b)1),2)
(Qult) Basler4
� � 4 4ult 1.0u y uM M Q Q� �� � (5.1)
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( )(My)
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,
3D-FEA( ) 4 I
2 I
22 ( )
I ( )
- 11 -
2(
) 1 /1
1990
�
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2 I( 80m) 1.0% ( ) 1.5% ( )
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PCa
FEA ( )2
AASHTO LRFDEC ( Class 2 )
: 1.88: 1.42
AASHTO LRFDEC ( Class 2 )
: 1.88: 1.42
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,
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- 15 -
- -
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( )
(12mm)
( )
( )
( )
- 16 -
LRFD
1990
300 1000
( )20
2030)
(2)
3D-FEA ()
1) ( ) 2002 2) ( ) 2012 3) 2007 [
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[ ] 2002 7) FEM
Vo.11, No.43, pp.131-145, 2004 8) PARTA ,
1998 9) JSSC
No.70, ( ) 2006 10)
A1, Vol.68, No.1, pp.16-27, 2012
11)A1, Vo.68, No.1, pp.203-215, 2012
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13) 2
- 17 -
Vol.45A, pp.1263-1272, 1999 14) 2 I 2
Vol.42A, pp.1061-1072, 1996 15) I
Vol.43A, pp.1141-1151, 1997 16) 2
Vol.4, No.15, pp.81-91, 1997 17) PC 2 -
Vol.5, No.20, pp.85-99 1998 18) 2 -
No.808/I-74, pp.75-86, 2006 19)
Vol.48A, pp.1417-1428, 2002 20)
Vol.48A, pp.1121-1130, 2002 21)
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26) 2 IA, Vol.66, No.1, pp.117-132, 2010
27) IA Vol.66, No.2, pp.393-405, 2010
28) F Vol.66, No.4, pp.647-659, 2010
29)F, Vol.67, No.4, pp.616-625, 2011
30) ( ) Vol.47, No.2, pp.1, 2013
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