Bond deterioration effects on corroded RC bridge pier in seismic zone

ARTICLE Bond deterioration effects on corroded RC bridge pier in seismic zone Mara Bartolozzi 1 | Joan R. Casas 2 | Marco Domaneschi 1 1 Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, Turin, Italy 2 Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya, Barcelona, Spain Correspondence Marco Domaneschi, Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Turin (TO), Italy. Email: [email protected] Abstract The effects of corrosion focusing on the consequences of bond strength deterioration for a reinforced concrete bridge pier in a seismic affected area are examined in this research. A bond degradation model based on the local bond stress-slip model presented in FIB Model Code 2010 is chosen. A motorway overpass object of a previous study, which considered the rebars cross-section reduction effect only, has been selected to assess the seismic capacity of the corroded pier in the time domain when bond degradation due to corrosion is also taken into account. The modification of strength capacity and ductility of the structural element is analyzed and the effect of corrosion during the whole service life of the structure is obtained. It is concluded that the effect of bond degradation is more critical for the safety of the pier than the effect of rebars cross-section loss. KEYWORDS bond strength, bridges, corrosion, reinforce concrete 1|INTRODUCTION Despite structures inevitably undergo to deterioration, which intensity depends on environmental conditions and the quality of the materials, an effective design, monitoring, and continuous targeted maintenance interventions can ensure the functionality and the safety of the structure for a long time. Focusing on reinforced concrete (RC) structures, corrosion of steel reinforcements reasonably represents the main reason for the shortening of their service life. The three main effects of steel rebars corrosion are the reduction of the rebar cross-section, the cracking of the concrete cover, and the decrease of the bond strength. 1 The use of a truthful bond strength degradation model represents the way to predict the evolution of the structure's strength and ductility over time and to be able to intervene before having a high level of damage or even the collapse of the structure. Therefore, it can be a critical tool for planning intervention and repair operations in efficient maintenance strategies. Corrosion is an electrochemical process, which consists of the transformation of iron into iron oxides, characterized by increasing volume and low mechanical properties that accumulate in the interface between steel and concrete. In this way, the bond strength is threatened both for the presence of an additional weak Discussion on this paper must be submitted within two months of the print publication. The discussion will then be published in print, along with the authors’closure, if any, approximately nine months after the print publication. Received: 25 October 2020 Revised: 15 July 2021 Accepted: 16 August 2021 DOI: 10.1002/suco.202000681 This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made. © 2021 The Authors. Structural Concrete published by John Wiley & Sons Ltd on behalf of International Federation for Structural Concrete. Structural Concrete. 2021;1–16. wileyonlinelibrary.com/journal/suco 1 layer between the two materials, the reduction of the mechanical bond interlocking because of the decrease of the rib height, and for the formation of cracks due to the radial pressure created by the high volume oxides. The mechanisms that contribute to bonding are chemical adhesion (at low stress level), friction, and mechanical interaction (high stress level) between the steel and the concrete. 2 Bond strength is influenced by the concrete cover/bar diameter ratio, the type of concrete, and the steel confinement. These factors influence the bond failure type too, which can occur for splitting or pull-out. The first one leads to the formation of cracks in concrete and to the slipping of the rebar. Differently, the pull-out failure is characterized by the crushing of the concrete around the bar without cracks formation, and it usually occurs in case of good confinement. 3 One of the first studies regarding the corrosion effect on the steel-concrete bond strength was carried out by Al-sulaimani et al., 4 which demonstrates that in correspondence to low level of corrosion there is an initial increase of the bond strength due to the pressure created by the expansive iron oxides before the cracking of the concrete cover. Such a result was confirmed by many authors, for example, References 5 and 6. Moreover, researches proved that confined concrete exhibits less reduction in the bond strength respect to the unconfined case. 5 Chung et al. 7 performed tests on flexural slabs with corroded reinforcement and the results showed that the decrease of moment capacity is mainly due to the deterioration of the bond between concrete and steel bars and secondarily to the loss of their cross-sectional area. Several of the early models that have been developed to represent the bond strength reduction in corroded structures do not consider the initial increase in bond strength, the stirrups and concrete cover confinement and the influence of the position of longitudinal reinforcement. 5,8 Recent models are characterized by higher accuracy and the capability to take into account several influencing factors. 9,10 Moreover, many models 5,11–13 are based on the relationship between bond strength and surface cracks width that was proved to be a valid indicator of the corrosion bond degradation. This research focuses on the determination of the bond strength deterioration effect on the seismic capacity of an RC bridge pier. The results are compared with those from a previous research 14,15 that designed the structure and developed a similar study based on the reinforcement area reduction effect only. The bond strength model chosen for the present research development is ARC2010, 16 as considered the most complete among the several analyzed for anchorage assessment in concrete structures with corroded reinforcements. Through interaction and Bresler's domains the effects of bond deterioration on the strength capacity of the pier have been evaluated, and a comparison with the results of the previous research (i.e., 14,15 ) is carried out. Moreover, the ductility of the element is checked plotting momentcurvature diagrams, considering and neglecting the bond strength reduction effect, in addition to the corrosion induced steel area loss. 2|BRIDGE CASE STUDY The bridge considered for the study is a motorway overpass located in Sicily, close to the strait of Messina, zone of high seismic hazard. A complete description of the geometry, structural conditions, and the seismic loading characterization can be found in References 14 and 15. However, in order to make the manuscript self-con- tained, some key general aspects are summarized below. 2.1 |The bridge structure and the adopted finite element model The structure is 55.5 m in length and consists of two spans, each one of 27.75 m. The deck is a solid slab in prestressed concrete with lightnings and variable depth (Figure 1, left). The bridge pier with “Y”shape is 6.70 m high and is the object of the present study. At the pier and the bents, support devices (elastomeric bearings) have been adopted. The foundation consists in a 5 5 2.5 rigid footing. The selected construction materials are Steel B450C and Concrete C40/50. 15 The two-span bridge has been implemented in SAP2000 as continuous beam, and a suitable finite element (FE) model has been created to perform the seismic analysis (Figure 1, right). The adopted discretization of each span considers six different sections. The Y-shaped pier has been modeled by frame elements: the two arms and the vertical shaft have been discretized in four different sections. The deck and the pier have been connected by the neoprene pads using rigid body constraints. 15 2.2 |Seismic analysis The bridge construction site belongs to the high seismic hazard area close to the Strait of Messina in Sicily (Italy). Indeed, it is classified as the first seismic category, associated by the highest seismic intensity, among four, by the current Italian standard for constructions NTC2018. 17 The seismic analysis has been performed as static linear analysis to verify the strength capacity of the individual structural elements and the whole structure, according to 2BARTOLOZZI ET AL. the demand actions associated to the SLV (life-saving limit state), the ultimate limit state for NTC2018. 17 The ductile behavior for the cross sections of the structural elements is prescribed and the “capacity design”criterion has been used. The design response spectra have been defined adopting the adequate behavior factor q. With this respect, the resulting peak ground accelerations in the horizontal and vertical directions result 0.332 g and 0.258 g, respectively. 14,15,17 The earthquake parameters have been the used in SAP2000 as “response spectrum”load. The seismic loads combination has been finally applied to the bridge computing the values of internal forces, that is, the axial forces, the bending moments and shears, at the two most critical sections of the “Y”shape pier, section A (base of the pier) and section B (base of the bifurcation) (Figure 2). Subsequently, the dimensioning of the longitudinal and transversal steel reinforcements have been performed following the Italian regulation 17 and the capacity design criteria. 14,15 3|CORROSION MODEL The implemented corrosion models refer to those ones adopted in a previous paper 15 of this research group, on the same case study, which considered the rebars cross-section reduction effect only. Some key aspects are summarized below to explain the modeling of metal bars cross-section losses. More details can be found referring to. 15 Corrosion of embedded steel bars affects RC structures and can be distinguished into two types: general and pitting. The first one is characterized by a roughly uniform and extensive metal loss over the reinforcing bar, while the second one is concentrated in small areas with higher steel area losses. Pitting corrosion mainly occurs in chloride environments, therefore if the structure is located in a marine environment, both corrosion types may occur in association. 18 The effect of the corrosion process on the steel bar is quantified with reference to the method presented in FIGURE 1 Bridge structure (left) and the FE model (right) FIGURE 2 Bridge pier geometry with steel reinforcements details for sections A and B BARTOLOZZI ET AL.3 Reference 19, where the residual reinforcement diameter d(t) is computed by Equation (1), the residual pitting depth p(t) at time t(assumed to take a hemispherical form) by Equation (2), and the residual cross-sectional area of steel bar A(t) due to general corrosion by Equation (3). 15 dtðÞ¼d02ðt tcorr λtðÞdt,ð1Þ ptðÞ¼Rðt tcorr λtðÞdt,ð2Þ AtðÞ¼ π 4dtðÞ½ 2:ð3Þ In Equations (1)–(3), the paramenter d 0 is the diameter of the intact reinforcement bar, Rthe amplification factor representing the ratio between maximum and uniform corrosion penetration, λ(t) the corrosion rate function. 15 4|BOND DETERIORATION MODEL ARC2010 bond degradation model is based on the local bond stress-slip model presented in Model Code 2010. 20 The local bond stresses are computed as a function of the relative displacement (slip) parallel to the bar axis and presented in the following Equations (4)–(7), while related parameters for different failure modes are reported in Table 1, where τ b is the tangential bond strength (MPa), τ b,max the maximum value of the tangential bond strength (MPa), τ res the residual tangential bond strength (MPa) (after splitting or pull-out and with stirrups confinement; without stirrups τ res =0), s(1,2,3) the slip values with respect to local bond strength, τ bu,split the tangential bond splitting strength (MPa), f cm the mean cylinder compressive strength (MPa), c clear the clear distance between ribs (mm) (ARC2010 16 ). τb¼τb,max s s1  α for 0 ≤s≤s1,ð4Þ τb¼τb,max for s1≤s≤s2,ð5Þ τb¼τb,max τb,max τres ðÞss2 ðÞ=s3s2 ðÞfor s2≤s≤s3, ð6Þ τb¼τres for s3≤s:ð7Þ ARC2010 bond degradation model allows for a complete representation of several scenarios. Indeed, different analytical expressions are provided for the computation of the bond strength, differentiating between cracked and un-cracked concrete cover. Both, pull-out and splitting failure can be represented and, in addition, the absence / presence of stirrups and their degree of corrosion can be considered. Several configurations can be truthfully represented thanks to the possibility to take into account the position of the longitudinal steel bar with respect to the RC element cross-section. In ARC2010 the expression used to compute the splitting strength for corrosion level below the cracking limit comes from Model Code 2010 (Equation (8)), while in the case of corrosioninduced cracking of the concrete cover a reduced bond splitting strength is considered (Equation (9)). Moreover, the residual bond stress has been modified for the case of low stirrup content (Equation (10)) and an equivalent slip is considered to take into account corrosion. 16 τbu,split ¼η2*6:5*fcm 25  0:25 *25 ϕm  0:2 cmin ϕm  0:25 cmax cmin  0:1 þkm*Ktr "# ,ð8Þ τbu,split,red ¼η2*6:5*fcm 25  0:25 *25 ϕm  0:2 1þkm*Ktr ðÞ,ð9Þ TABLE 1 Parameters for local bond stress-slip curve for MC 2010 “good bond conditions” Pull out Splitting –Unconfined Splitting –Stirrups τb,max (MPa) 2:5ffiffiffiffiffiffiffi fcm p2:5ffiffiffiffiffiffiffi fcm p2:5ffiffiffiffiffiffiffi fcm p τbu,split (MPa) / Equation (8) Equation (8) s1(mm) 1 sτbu,split sτbu,split s2(mm) 2 s1s1 s3(mm) cclear 1:2s10:5cclear α0.4 0.4 0.4 τres (MPa) 0:4τb,max 00:4τbu,split 4BARTOLOZZI ET AL. τres,mod Ktr ðÞ¼0:16þ12Ktr ðÞ*τbu,split,red for 0 ≤Ktr ≤0:02 0:4*τbu,split,red for 0:02 < Ktr : ð10Þ Adopted variables in Equations (8)–(10) are explained in the following: •η2is 1 for “good bond conditions”(bars with inclination of 45–90respect to the horizontal ones during concreting and to those ones with inclination lower than 45but at a distance up to 250 mm from the bottom and at least 300 mm from the top of the concrete layer) and 0.7 for “all other bond conditions”; •ϕmdiameter of the anchored bar (mm); •kmconfinement coefficient (12 for bars within 5ϕm≤125 mm from a stirrup corner, 6 if cs>8cyand 0ifcs<8cyor if a crack can propagate to the concrete surface without crossing transverse links; cmin ¼min cs=2,cx,cy  ; cmax ¼max cs 2,cx  ; •csclear spacing between main bars (mm); •cx,cycover in x and y directions (mm); •Ktr amount of transverse reinforcement =ntAst=nbϕmst ðÞ≤0:05; •ntnumber of legs of confining reinforcement crossing a potential splitting-failure surface at a section; •Ast cross - sectional area of one leg of a transverse bar (mm2); •stlongitudinal spacing of confining reinforcement (mm); •nbnumber of anchored bars or pairs of lapped bars in the potential splitting surface. 5|CORROSION, BOND DETERIORATION, AND THE BRIDGE CASE STUDY 5.1 |Slip-bond strength relationship The slip - bond strength relationship has been obtained for section A and B in the direction xand yconsidering three different cases: (i) pull-out failure, (ii) splitting failure in absence of stirrups, and (iii) splitting failure in presence of stirrups. Table 2 reports ARC2010 model parameters for sections A and B. As an example, Figure 3 shows the bond-slip curve of section A in xdirection (Ax). All the values refer to the instant t=0 (uncracked concrete) when the corrosion attack did not start yet. The amount of transversal reinforcement is an input parameter of the model, assuming that is subjected to the same corrosion deterioration rate as the longitudinal steel reinforcement. Therefore, different bond-slip curves per each corrosion level are verified. The reduction of the cross - sectional area of the TABLE 2 Cross-section properties and ARC2010 model parameter for sections A and B fcm (MPa) 48 cs(mm) 50 cx(mm) 50 cy(section B) (mm) 50 nt(section A,x)6 nt(section A,y)4 nt(section B)4 nb(section A,x)20 nb(section A,y)9 nb(section B,x)18 nb(section B,y)17 cclear (mm) 5.8 st(mm) 60 cmin (section A) (mm) 25 cmin (section B) (mm) 25 cmax (mm) 50 km12 FIGURE 3 Bond strength –Slip relationship ARC2010 model for section A, x direction (t=0) (continuous line =pull-out failure, long-dashed line =splitting failure in absence of stirrups, shortdashed line =splitting failure in presence of stirrups) BARTOLOZZI ET AL.5 longitudinal reinforcement is considered as in Reference 14 and it is assumed equal for the stirrups. Once the variation of the stirrups area in time is known, the bond splitting strength has been computed for different value of Ktr, the parameter that takes into account the amount of transversal reinforcement. The computation has been performed for the two cross sections in both xand ydirections and for both general and pitting corrosion. They are characterized by different area reduction in time domain. Moreover, the coupled condition of general and pitting corrosion acting at the same time has been considered. Table 3 reports as an example the variation of the bond strength for different degree of corrosion of the stirrups for section Ax. 5.2 |Deteriorated bond strength The local bond stress-slip curve of corroded reinforcement is approximated shifting the uncorroded curve in the slip direction and considering the minimum value of both, the original and the shifted curve. The additional slip used to shift the curve is the equivalent slip that can be correlated with the corrosion level (in RC elements with stirrups) according to the following equation for the equivalent slip Seq,stir (mm) as function of the corrosion level (steel weight loss) Wc: Seq,stir ¼13:6Wc:ð11Þ Once the equivalent slip is computed, the bond strength-slip curves have been translated in order to find the intersection point between the original curve and the new one, representing the deteriorated bond strength at a specific corrosion level. According to experimental results, it is assumed that the cracking of the concrete cover occurs at a corrosion level of 2%. Then the reduction of bond strength in time domain has been computed for section A and B in both xand ydirections and has been compared with the steel area reduction in time. The resulting decrease is emphasized during the whole service life of the structure for both the considered corrosion attacks (general and pitting). Reductions occur during the corrosion propagation phase, after the steel depassivation, so during the first years no area and bond strength loss are verified. The comparison plots for section Ax in the cases of general, pitting, and general + pitting corrosion are reported in Figures 4–6. They emphasize how bond degradation is the most demanding effect of corrosion in the RC bridge pier. 5.3 |Cross-sectional losses due to general and pitting corrosion The effect of corrosion of the cross-sectional area losses have been investigated in detail in Reference 15 for longitudinal rebars. The general outcomes have been summarized by Table 4 with deteriorated bond strength for section Ax. When general and pitting corrosion are considered separately, their effects in terms of area losses are roughly comparable, even if pitting is more demanding. However, the worst case is represented by their associated effect. Similar outcomes can be highlighted also by considering the resulting deteriorated bond strength: with the association of both general and pitting corrosion determine the most dangerous condition, with respect to their separate effects. Results for sections Ay, Bx, By are TABLE 3 Variation of the bond strength for different degree of corrosion of the stirrups in section Ax t (years) As(t) (General) (mm 2 )Ktr τbu,split (General) (MPa) As(t) (Pitting) (mm 2 )Ktr τbu,split (Pitting) (MPa) As(t)(G +P) (mm2) Ktr τbu,split (G +P) (MPa) 0 154.00 0.0241 9.4412 154.00 0.0241 9.4412 154.00 0.0241 9.4412 10 153.04 0.0239 9.4282 154.00 0.0241 9.4412 153.04 0.0239 9.4282 20 148.06 0.0231 9.3046 152.66 0.0239 9.4229 146.72 0.0229 9.3418 30 142.12 0.0222 9.2235 148.45 0.0232 9.3098 136.57 0.0213 9.1477 40 136.95 0.0214 9.1529 142.51 0.0223 9.2287 125.46 0.0196 8.9960 50 132.16 0.0207 9.0875 135.42 0.0212 9.1320 113.58 0.0177 8.8338 60 127.95 0.0200 9.0300 127.38 0.0199 9.0221 101.33 0.0158 8.6664 70 123.93 0.0194 8.9750 119.33 0.0186 8.9123 89.26 0.0139 8.5016 80 120.10 0.0188 8.9227 110.52 0.0173 8.7919 76.62 0.0120 8.3290 90 116.46 0.0182 8.8730 101.33 0.0158 8.6664 63.78 0.0100 8.1537 100 113.20 0.0177 8.8286 92.13 0.0144 8.5408 51.33 0.0080 7.9837 6BARTOLOZZI ET AL. not shown for the sake of brevity since the values are slightly different due to the different reinforcement and geometry but the reduction in adhesion does not change significantly. 6|STRUCTURAL CAPACITY AND DUCTILITY 6.1 |Interaction domains Interaction domains are used to assess the seismic performance of the bridge pier that results simultaneously subjected to axial and bending stresses. The input parameters for the construction of the interaction domains that have been modified to consider the effects of corrosion are steel rebar cross-section, steel yield strength, and steel ultimate strain. 14,15 Therefore, the reductions along time of the three input parameters have been computed for the cases of general corrosion, pitting corrosion, and their coupled effect. In order to take into account in the present study the effect of bond strength degradation in the cross-sectional capacity, the following hypothesis has been made. It is assumed that, according to an optimal design, the initial bond strength in the undamaged state, taking into account the anchorage length or the lap splice of the rebars, is that one able to bond the rebar working at the yield strength. Due to the degradation of the bond strength with increasing corrosion, the yield strength in the rebar cannot be anymore accommodated by the rebar. Consequently, it has been assumed that the percentage reduction in the bond strength is the same in the maximum tensile strength that the reinforcing steel can develop. So, the degradation of the bond strength, that prevents the material to reach the yielding point and to exhibit a plastic behavior, is modeled by decreasing proportionally the maximum steel strength and the corresponding strain in the linear-elastic part of the stress-strain relationship. In other words, the same decrement that undergoes the bond strength has been considered for the steel yield strength, assuming null post-yielding stiffness, and the maximum strain has been fixed accordingly. This assumption has been experimentally validated as shown at Section 7. Figures 7–12 show the interaction domains comparing the outputs of the previous study 15 and the present one, for cross sections Ax and By at 0, 20, 40, 60, 80, and 100 years, in the cases of general, pitting, and general + pitting corrosion. The new domains, show that the decrease in adherence strongly affects the structural capacity of the pier. Comparing the resistant domains, a substantial reduction can be observed when the bond FIGURE 4 Comparison between area and bond strength reduction (general corrosion - section Ax) FIGURE 5 Comparison between area and bond strength reduction (pitting corrosion - section Ax) FIGURE 6 Comparison between area and bond strength reduction (general +pitting corrosion - section Ax) BARTOLOZZI ET AL.7 strength deterioration is considered. Section Ax and By are those undergoing an early failure. 6.2 |Bresler's domains Bresler's domains allow to evaluate the capacity of the structural elements subjected to biaxial bending and axial load. The 2D plots have been obtained for a fixed value of axial load (maximum load acting on the considered section) and present the resistant moments in y and x directions. The resulting domains are strongly reduced if the effect of bond deterioration is considered. The Bresler's domains obtained from the previous study 15 (100 years NB =no bonding effect) and those ones computed in the present study have been compared for the three corrosion cases and both sections A and B (Figures 13–15). The largest continuous line represents the domain of the no corroded section. The medium and the smallest dashed ones represent the resistant domains after 100 years, considering the steel bars area loss effects and the area loss with bond strength reduction effects, respectively. Early failure of section A is expected when subjected to all different types of corrosion conditions if the degradation of bond strength is considered, while it occurs only in the case of pitting and general corrosion acting simultaneously if steel area loss effect only is taken into account. Differently, the results highlight an early failure of section B for any corrosion attack typology with and without considering bond degradation effects. 6.3 |Moment-curvature diagrams Apart from strength, also ductility of the cross-sections is also a fundamental property for concrete structures located in seismic zones. In seismic design, ductility is an indicator of the capability to reach high level of TABLE 4 Cross-section losses and deteriorated bond strength due to general and pitting corrosion for section Ax General corrosion Pitting corrosion G +P corrosion t(years) A(t) (mm 2 ) Deteriorated bond strength (MPa) A(t) (mm 2 ) Deteriorated bond strength (MPa) A(t) (mm 2 ) Deteriorated bond strength (MPa) 0 804 9.44 804 9.44 804 9.44 20 773 8.32 797 9.2 766 8.08 40 715 6.34 744 7.33 655 4.26 60 668 4.74 665 4.63 529 3.03 80 627 3.44 577 3.23 400 2.53 100 591 3.29 481 2.84 268 2.04 FIGURE 7 Interaction domain my-N of section A due to general corrosion considering (left) and neglecting (right) bond reduction effect 8BARTOLOZZI ET AL. deformation before the failure, avoiding sudden collapse of the structure and, therefore, allowing to intervene in advance. Through the moment-curvature diagram, it is possible to estimate the curvature ductility of a reinforced concrete section The variation of the RC pier ductility along time is assessed through the construction of moment- FIGURE 8 Interaction domain mx-N of section B due to general corrosion considering (left) and neglecting (right) bond reduction effect FIGURE 9 Interaction domain my-N of section A due to pitting corrosion considering (left) and neglecting (right) bond reduction effect FIGURE 10 Interaction domain mx-N of section B due to pitting corrosion considering (left) and neglecting (right) bond reduction effect BARTOLOZZI ET AL.9 9. Coronelli D. Corrosion cracking and bond strength modelling for corroded bars in reinforced concrete. ACI Struct J. 2002;99: 267–76. 10. Lin H, Zhao Y. Effects of confinements on the bond strength between concrete and corroded steel bars. 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Nucl Eng Des. 2008;238(12):3194–202. https://www.sciencedirect.com/science/article/pii/S002954930 8004500?casa_token=nA45SUDQrI8AAAAA:ny8Bo09v_JO0U txzi6CarE-oi_gMT6CJivZexx_FmDeeqrZ396TU0XhpfNohUJE2I WdtXpJBbA AUTHOR BIOGRAPHIES Mara Bartolozzi, Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, Turin, Italy. Email: [email protected] Joan R. Casas, Department of Civil and Environmental Engineering, Universitat Politècnica de Catalunya, Barcelona, Spain. Email: joan. [email protected] Marco Domaneschi, Department of Structural, Geotechnical and Building Engineering, Politecnico di Torino, Turin, Italy. Email: marco. [email protected] How to cite this article: Bartolozzi M, Casas JR, Domaneschi M. Bond deterioration effects on corroded RC bridge pier in seismic zone. Structural Concrete. 2021;1–16. https://doi.org/10.1002/suco. 202000681 16 BARTOLOZZI ET AL.