TY - JOUR

T1 - Strengthening of prestressed girder-deck system with partially debonding strand by the use of CFRP or steel plates

T2 - Analytical investigation

AU - Ni, Haoran

AU - Li, Riliang

AU - Aboutaha, Riyad S.

N1 - Funding Information:
Due to the doubly symmetric characteristics of the model, only a quarter of the girder-deck system was modelled with the consideration of running time reduction. Using the z-direction symmetry, the girder-deck system was divided into two parts with a plane parallel to x-y plane. The displacement in z-direction and the rotation around x, y-directions were constrained by a roller supports (U3=UR1=UR2=0). Similarly, using the x-direction symmetry, the girder-deck system was cut with a plane parallel to y-z plane. The displacement of x-direction and the rotation around y, z-direction were constrained by a roller supports (U1=UR2=UR3=0). Additionally, the girder-deck system was supported with roller supports constraining the displacement in y-direction at the support (U2=0). The boundary conditions for the models are shown in Fig. 5
Publisher Copyright:
Copyright © 2023 Techno-Press, Ltd.

PY - 2023/4

Y1 - 2023/4

N2 - This paper describes an in-depth analysis on flexural strength of a girder-deck system experiencing a strand debonding damage with various strengthening systems, based on finite element software ABAQUS. A detailed finite element analysis (FEA) model was developed and verified against the relevant experimental data performed by other researchers. The proposed analytical model showed a good agreement with experimental data. Based on the verified FE model, over a hundred girder-deck systems were investigated with the consideration of following variables: 1) debonding level, 2) span-to-depth ratio (L/d), 3) strengthening type, 4) strengthening material thickness. Based on the data above, a new detailed analytical model was developed and proposed for estimating residual flexural strength of the strand-debonding damaged girder-deck system with strengthening systems. It was demonstrated that both finite element model and analysis model could be used to predict flexural behaviors for debonding damaged prestressed girder-deck systems. Since the strands are debonding from surrounding concrete over a certain zone over the length of the beam, the increase of strain in strands can be linked with a ratio Ψ, which is Lp/c. The analytical model was proposed and developed regarding the ratio Ψ. By conducting procedure of calculating Ψ, the Ψ value varies from 9.3 to 70.1. Multiple nonlinear regression analysis was performed in Software IBM SPSS Statistics 27.0.1 to derive equation of Ψ. Ψ equation was curved to be an exponential function, and the independent variable (X) is a linear function in terms of three variables of debonding level (λ), span length (L), and amount of strengthening material (As). The coefficient of determinate (R2) for curve fitting in nonlinear regression analysis is 0.8768. The developed analytical model was compared to the ultimate capacities computed by FEA model.

AB - This paper describes an in-depth analysis on flexural strength of a girder-deck system experiencing a strand debonding damage with various strengthening systems, based on finite element software ABAQUS. A detailed finite element analysis (FEA) model was developed and verified against the relevant experimental data performed by other researchers. The proposed analytical model showed a good agreement with experimental data. Based on the verified FE model, over a hundred girder-deck systems were investigated with the consideration of following variables: 1) debonding level, 2) span-to-depth ratio (L/d), 3) strengthening type, 4) strengthening material thickness. Based on the data above, a new detailed analytical model was developed and proposed for estimating residual flexural strength of the strand-debonding damaged girder-deck system with strengthening systems. It was demonstrated that both finite element model and analysis model could be used to predict flexural behaviors for debonding damaged prestressed girder-deck systems. Since the strands are debonding from surrounding concrete over a certain zone over the length of the beam, the increase of strain in strands can be linked with a ratio Ψ, which is Lp/c. The analytical model was proposed and developed regarding the ratio Ψ. By conducting procedure of calculating Ψ, the Ψ value varies from 9.3 to 70.1. Multiple nonlinear regression analysis was performed in Software IBM SPSS Statistics 27.0.1 to derive equation of Ψ. Ψ equation was curved to be an exponential function, and the independent variable (X) is a linear function in terms of three variables of debonding level (λ), span length (L), and amount of strengthening material (As). The coefficient of determinate (R2) for curve fitting in nonlinear regression analysis is 0.8768. The developed analytical model was compared to the ultimate capacities computed by FEA model.

KW - analytical model

KW - CFRP

KW - debonding strands

KW - finite element analysis

KW - flexural strength

KW - prestressed concrete

UR - http://www.scopus.com/inward/record.url?scp=85163145110&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85163145110&partnerID=8YFLogxK

U2 - 10.12989/cac.2023.31.4.349

DO - 10.12989/cac.2023.31.4.349

M3 - Article

AN - SCOPUS:85163145110

SN - 1598-8198

VL - 31

SP - 34

EP - 358

JO - Computers and Concrete

JF - Computers and Concrete

IS - 4

ER -