COST Action TU 0904 “St. CIRIL and METHODIUS” UNIVERSITY FACULTY OF CIVIL ENGINEERING SKOPJE - MACEDONIA Cvetkovska Meri Lazarov Ljupco Todorov Koce examination, assessment and repair of fire damaged rc structure of „refinery-okta“ in skopje

VIEW OF THE FIRED STRUCTURE COST Action TU 0904 VIEW OF THE FIRED STRUCTURE Model of structure in SAP2000

Schematic presentation of the fired structure COST Action TU 0904 R1(G1- 55*100cm) B3 (30*60cm) R1 9 m B3 B2 (45*60cm) 6 m B1-less fire exposed beam Schematic presentation of the fired structure

1. VISUAL INSPECTION OF STRUCTURE COST Action TU 0904 1. VISUAL INSPECTION OF STRUCTURE Red color indicate temperaures round 6000C Flexy color indicate temperaures round 9000C Deformation of crane beam because of the restrained dilatation

2. Experimental determination of the residual concrete strength COST Action TU 0904 2. Experimental determination of the residual concrete strength Before testing all the specimens were divided in two slices. The deteriorated (burned) slices had small height (3-6 cm) and rough surface The speciment were taken without the destruction of reinforcement and were tested at the Testing laboratory of the Faculty of Civil Engineering in Skopje

COST Action TU 0904 TESTING EQUIPEMENT Results of strength tests on samples that were not exposed to fire Average strength of concrete exposed to fire was 9,24 MPa

Numerical determination of the residual concrete strength COST Action TU 904 Numerical determination of the residual concrete strength el.3 el.4 el.1 el.2 b) 22.5cm axis of symmetry 22.5cm 428 628 222 228 a) axis of symmetry Isotherms in the cross section of the beam B2 (t=1.5hours), residual concrete strength after cooling phase

Numerical determination of the residual concrete strength COST Action TU 904 Numerical determination of the residual concrete strength 17.5cm 432 425 a) axis of symmetry el.3 el.4 el.1 el.2 b) Isotherms in the cross section of the beam G2 (t=1.5hours), b) residual concrete strength after cooling phase

Nonlinear thermal analysis COST Action TU 904 Nonlinear thermal analysis Time dependent temperatures of the reinforcing bars Beam B2 which is exposed to fire from three sides Beam G2 which is exposed to fire from three sides

Nonlinear stress-strain analysis COST Action TU 904 Nonlinear stress-strain analysis Time dependent stresses of reinforcement no.3 of beam B2, for cross section at mid span -1 -0,5 0,5 1 -6,5 -5 -3,5 -2 el.2(at the support)-heating phase el.2(at the support)-cooling phase el.2(at the mid span)-heating phase el.2(at the mid span)-cooling phase , as % of fy (T) t=0= + 8Mpa t=0=-14Mpa t= e *1000

Nonlinear stress-strain analysis COST Action TU 904 Nonlinear stress-strain analysis -0,2 0,2 0,6 1 -0,5 0,5 1,5 2 2,5 el.3-heating phase el.3-cooling phase -0,6 e *1000 , as % of fy (T) t=0= -4Mpa t==-217Mpa Time dependent stresses of reinforcement no.3 of beam B2, for cross section at mid span

Suggested repair of fire damaged structural elements COST Action TU 904 Suggested repair of fire damaged structural elements 572.5 27.5 100 cm G1 60 cm existing reinforcement 428 + 220 (additional reinforcement) concrete cover to be eliminated up to the existing stirrups beam B2 Repair details of beam B2

Suggested repair of fire damaged structural elements COST Action TU 904 Suggested repair of fire damaged structural elements

Suggested repair of fire damaged structural elements COST Action TU 904 Suggested repair of fire damaged structural elements

Thank you for the atTention