Seismic Vulnerability Assessment of Steel-Concrete Composite Bridges by Analytical Modeling with Case Study

Transcription

1 - 3 1 (88/6/18: 88/1/15: )..... " " Seismic Vulnerability Assessment of Steel-Concrete Composite Bridges by Analytical Modeling with Case Study A. Gharighoran F. Daneshjoo Reza Akbari Abstract The seismic vulnerability of a steel-concrete composite slab-on-girder bridge has been assessed in this paper.firstly quantity assessment of the bridge has been done and through an in-depth inspection program all the defects were detected. Then based on the purposes of this study appropriate Finite Element (FE) model has been created and the vulnerability assessment of the bridge has been carried out. In between the above mentioned phases some destructive and non-destructive tests were carried out in order to find the mechanical properties of the materials as-well-as the characteristics of the surrounding soils. It has been tried to use a rational modeling for the expansion joints of "balanced type" as-well-as for the special steel bearings of the bridge. Two different FE models with different levels of accuracy and different element types have been used to increase the reliability of the models and the FE models of the bridge has been updated in a procedure with comparing the modal results of the above mentioned models. Finally the seismic vulnerability of the bridge has been assessed through the standard procedure of seismic spectral analysis of the bridge. Capacity-demand ratios for all the bridge components and elements have been calculated. The results showed that the bridge have adequate seismic performance against Iranian seismic code (standard 800). It was found that the bridge has a low level of seismic vulnerability. The study showed that the bridge still enjoyed relatively appropriate strength reserve and proper dynamic performance despite some minor cracks and steel corrosion suffering from carbonation and poor maintenance. Kerwords Steel-Concrete Composite Bridges Seismic vulnerability Finite Element Modeling. ( ) gharighoran@yahoo.com -.1 danesh_f@modares.ac.ir -. rakbari@ut.ac.ir.3 59/

2 Cypress..[] : [1] / 60

3 . - AII.[3] /8... (1) " " (3).. (3).. (4). (5) ST [3] " ".. - ( ) [1]. (1) (). 10 () /

4 .... :(1) PL 390x10 L 100x100x10 WEB 1700x10 :() ( ) " " :(3) 1388 / 6

5 .( ) :(4). 1 :(5) ).[11] ( [] FHWA - C/D [] FHWA-.. " " - [] FHWA /

6 .( ) (6)..[6] C/D. ( ).[] -.. [5]. : [] FHWA. [11] / 64

7 -. ( ) SAP000 v SAP ( ) -( ) -( ) -( ).. -5 (7) /

8 . SAP000. (9).. (8) [5] :(6) 1388 / 66

9 [7] :(7) SHELL :(8) FRAME :(9) :(10) 67/

10 . Gap... (1) -.. Gap. ( ) :(11) 45 R ( ) :(1) -4-6 (1) " " 4 (3). (1) (10) (5) (11) /

11 .[7]. ) : ( N / mm k GA N mm (4) h h 100 / A S 1.5 (5) h( L W ) 00 (1000) 6GS Ak k v 338 N / mm (6) (6GS k) h (13) :(1) k(mpa) 000 G (MPa) cm 50 cm 50 cm.[7] GA k h h (1) 0/66 ) G h A ( /07. :[7] 6GS Ak k v (6GS k) h 000 ) k () () S ( L W :[7] A S (3) h( L W ) 5-15.[7] NLLINK. SAP000 Rubber Isolator 69/

12 [] FHWA.. FEMA- 356.[9].. ) ( /75. :(13) [9] FEMA. 0/5 [] FHWA. : (7) (G 0 ) Vs G0 (7) g V s g / 70

13 (-4) G.[6] kg G (10) cm.. 1.3G kg K sv 0.68 (11) 3 B(1 ) cm. (-6) [10]. ). SAP000 (... ( ) /5 150kg / m kg / m.. - G 4375 N 1/ 3 0 [( 1) 60] (N 1 ) : (8) (kpa) G 0 SPT. (kpa) (G ) -.[6] : -1. G -.. [4] 800 IV IV V s 175 m / s.[4] : (7) G Vs E6 g 9.81 kg m (9) 71/

14 (35 ) [11] CQC SRSS [10] 139 (4-1) ( DL ) ( MOV1 ) ( EY ) ( EX ).( MOV ) (EZ ) ) (. SAP000 ().. EZ EY EX DL [10]..[11] kN / m... ( )..[9] / 7

15 F b 0.55F 410 (1) y. (3) F v 0.33F 1440 y (4) [10] 139 0/001. ( ).. (5) (15) R. MOV1 MOV [1] ) n. ( n... (1 1 (3 (. (4 1 ( 40).. : 73/

16 .. :() EZ EY EX MOV MAX MOV MIN MOV1 MAX MOV1 MIN DL COMBO G G G G G G G G G G G G G6- :(15) 1388 / 74

17 A st I st ( ) :(3) y I tr S max S min M all E E E E E E5 :(4) ( ) G6- G6-1 G5-8 G5-7 G5-6 G5-5 G5-4 G5-3 G5- G5-1 G- G-1 G ( ) D/C G6- G6-1 G5-8 G5-7 G5-6 G5-5 G5-4 G5-3 G5- G5-1 G- G-1 G :(5) Mode No. Period M eff -X M eff -Y M eff -Z Mode No. Period M eff -X M eff -Y M eff -Z /

18 FHWA (6) (7).. 1 G6 G. 1 - ( ) (8) (13) :[7] ' A b B 1 (13) A ' A B 0/7 0/4 A.[7] /67 3/ (1) 1/5. 0/3 / /44 7 A '. 76/

19 :(6) D/C G6- G6-1 G5-8 G5-7 G5-6 G5-5 G5-4 G5-3 G5- G5-1 G- G-1 G :(7) D/C G6- G6-1 G5-8 G5-7 G5-6 G5-5 G5-4 G5-3 G5- G5-1 G- G-1 G :(8) D/C G6- G6-1 G5-8 G5-7 G5-6 G5-5 G5-4 G5-3 G5- G5-1 G- G-1 G /

20 kgf cm kgf cm 1.5 kgf cm.. [] FHWA /

21 N ( (16) ) 305mm 1400 ok 35 ) : ([11] N L 0.01H (17) m ok : ([] FHWA ) C/D C N( c) 1400 ) (18) D B W N( d) 757. (. 35. [] FHWA L. (14) (3) : N ( ( ) (19) ) 37mm 630 ok FHWA D(d).. 75 D(c).[] ( ) :[5] (14) N ( L H ) ( s ) (14) L (mm) N H (mm) ( ) S (mm) :. IV N ( L H ) ( s ) 1 (15) : 79/

22 C/D [] FHWA (1). Vb ( c) rbf (0) Vb ( d) V b (c). V b (d) 1/ : 1/5 r bf Vb ( c) 4 V ( d) b 0.54 (1). 1 ANSYS / 80

23 Priestley M. J. N. Calvi G. M 1996 Seismic Design and Retrofit of Bridges John Wiley & Sons Inc.. 8- FEMA Prestandard and Commently for the Seismic Rehabilitation of Building Prepared by the ASCE The Federal Emergency Management Agency Washington DC. " " " " " "FHWA " ". 5- AASHTO 004 American Association of State Highway and Transportation Officials AASHTO LRFD Bridge Design Specification 3rd Edition Washington. 81/