Concrete Jacketing Research Articles

Retrofitting RC beam-column joint subassemblies using UHPC jackets reinforced with high-strength steel mesh

Outdated building codes in seismic zones often did not require seismic detailing on beam-column joints, leaving many existing structures vulnerable to earthquakes. To address this issue, three different ultra-high-performance concrete (UHPC) jackets were proposed for retrofitting seismically-deficient exterior beam-column joints, with variables including construction method (cast-in-place or precast) and inclusion of high-strength steel bar meshes. The effectiveness of these jackets was investigated using cyclic loading tests on beam-column joint subassemblages. The results demonstrated that all three UHPC jackets considerably improved the strength, stiffness, and energy dissipation of the beam-column joint subassemblage, as well as both repairable and collapse drifts. However, the cast-in-place UHPC jacket, when not reinforced with steel meshes, failed to effectively improve the ultimate drift capacity of the original beam-column joint subassemblage. Moreover, retrofitting with precast UHPC jackets using chemical anchors failed to generate sufficient composite action. Only the cast-in-place UHPC jacket, when reinforced with high-strength steel meshes, successfully delayed localized joint shear damage and allowed for effective utilization of beam flexural capacity. It improved the joint shear strength by 66%, initial stiffness by approximately 35%, and total energy dissipation by 140%. Finally, strength models were suggested for evaluating the joint shear strength and beam flexural capacity of UHPC-retrofitted beam-column joints.

Seismic retrofitting of RC columns using stainless steel grid-reinforced UHPC jackets in plastic hinge zone

This study aims to propose a new seismic retrofitting method for reinforced concrete (RC) columns in buildings with insufficient or flawed design in early standards by locally using stainless steel grid-reinforced ultra-high performance concrete (UHPC) jackets in the plastic hinge zone. For this purpose, pseudo-static loading tests were conducted on four rectangular columns with economical reinforcement ratios, including three retrofitted columns and one traditional RC column, and the effects of the number of stainless steel grid layers and the height of UHPC jackets were investigated. Additionally, a fiber-based finite element model was developed for the retrofitted columns and its accuracy was verified. The influence of other parameters not considered in the experiment, such as the axial compression ratio, UHPC jacket thickness and concrete compressive strength on the seismic performance of the retrofitted columns were also analyzed. The results demonstrated that the proposed retrofitting method effectively improves the seismic behavior of RC columns in a quick and cost-effective manner. The combination of stainless steel grids and UHPC jackets provided stable confinement for the internal RC columns, significantly reducing the damage in the plastic hinge zone and the residual displacements. Compared with the RC column, the ductility, bearing capacity and energy dissipation of the retrofitted columns were enhanced. Especially, the ductility coefficient of the specimens using a two-layer stainless steel grid increased by 27.19 %–36.56 %.

Revitalizing Infrastructure: Assessing Concrete Jacketing for Reinforced Concrete Column Rehabilitation

The rehabilitation of deteriorating civil engineering infrastructure, encompassing bridges, buildings, columns, beams, supporting beams, marine structures, and roads, presents a formidable challenge in contemporary engineering practice. As society's demand for upgraded infrastructure escalates, the imperative to address deteriorating structures becomes increasingly urgent. Consequently, the rehabilitation of existing infrastructure has been identified as a paramount concern warranting immediate attention. Among the myriad techniques employed, retrofitting columns with concrete jacketing stands out as one of the most prevalent methods for enhancing column strength. This investigation delves into the efficacy of concrete jacketing as a means of revitalizing reinforced concrete columns. The results evince a substantial augmentation in column capacity following retrofitting, underscoring the potential of such methods to bolster the load-bearing capabilities of reinforced concrete columns. Furthermore, the analysis reveals a more uniform stress distribution in retrofitted columns compared to their unmodified counterparts, thereby mitigating issues related to uneven stress distribution. In summation, the findings underscore the considerable promise of concrete jacketing in fortifying the strength, structural integrity, and longevity of deteriorated infrastructure.

Experimental and numerical investigation on axial behavior of circular and square slender reinforced columns

To investigate the axial performance of slender concrete-filled steel tube (CFST) columns reinforced by outer steel tube and sandwiched concrete jackets, an axial compression test was conducted on 20 circular and square slender reinforced columns. The study aimed to examine the influence of the cross-sectional shape, steel content of the outer tube, the strength of sandwiched concrete, and slenderness ratio on the failure mode, load-displacement curves, and ultimate load. A comparative test on six slender CFST columns was also conducted. The test results showed that the local buckling degree of the outer steel tube in square reinforced columns was greater than that in circular reinforced columns, while the overall bending deformation was smaller. The influence of the sandwiched concrete strength on the load-displacement curve was weaker compared to the influence of the outer tube thickness and slenderness ratio. As the slenderness ratio increased, both the longitudinal and lateral strains of the specimens tended to decrease. The difference in strain between the tension and compression sides was more pronounced in circular reinforced columns than in square reinforced columns. The average SI values of circular and square reinforced specimens were 1.05 and 1.00, respectively, but the gap in SI values between the two types of reinforced columns is reduced as the slenderness ratio increases. Then, a numerical model on the slender reinforced columns was established by the finite element software ABAQUS. A good agreement was obtained between test results and simulation results. The mechanical mechanism of typical slender reinforced columns was further analyzed, including longitudinal stress contour map of concrete, the development of longitudinal stress of steel tube, as well as distribution of transverse confinement stress. A formula was subsequently proposed based on a design code to predict the load-bearing capacity of the retrofitted columns, the prediction results agreed well with the experimental data.

Size effect on axial behavior of stub CFST columns strengthened with square steel tube and sandwiched concrete jackets

The size effect of CFST columns strengthened with square steel tube and sandwiched concrete jackets subjected to axial compression was investigated. Test parameters included specimen size, outer steel ratio and sandwiched concrete grade. The test results showed that the peak nominal stress and ductility index of both CFST and strengthened columns presented a decreasing tendency with the increase of the specimen size. Compared with traditional CFST columns, the size effect on peak stress of retrofitted columns was found to be more significant, while the size effect on ductility index was weaker. The analysis revealed that the level of confinement stress decreased as the size of the confined concrete increased at the peak load. The size effect on the confining stress was much greater than that on the material strength of the sandwiched concrete. Comparison results with four design codes indicated that the existing specifications overestimated the load-bearing capacity of large-size specimens. A formula for calculating the reduction coefficient related to confinement ratio was proposed to consider the size effect on the compressive strength of inner and sandwiched concrete. By introducing the reduction coefficients into formulas of design codes, the trend of overestimating the load-bearing capacity of large-size columns was weakened.

Hybrid strengthening scheme for reinforced concrete beams: Flexural behaviour and large-scale testing

Revision of design standards, new regulations, and planned/unplanned increases in loadings potentially make buildings vulnerable to changes in capacity demands. This may result in some structural components of an existing structure requiring strength or stiffness improvement. Strengthening of capacity deficit members is widely recognised as the preferred and sustainable choice in terms of conserving resources and minimising the carbon footprint. Strengthening techniques such as Reinforced Concrete (RC) jacketing, steel jacketing and Fibre Reinforced Polymer (FRP) wrapping have been explored and widely used. However, when adopted solely, each scheme has its drawbacks. RC jacketing results in a considerable rise in the dead load, influencing the loading on the foundation and restricting the functional space available post-jacketing. Steel jacketing often lacks flexibility as a significant effort is required for installation. FRP improves the flexural strength response but produces low stiffness enhancement and lesser ductility. A hybrid strengthening option, i.e. a combination of the above strengthening methods, presents a viable option to address the limitations cost-effectively. This paper presents a pioneering attempt focused on improving the flexural performance of RC beams using a hybrid strengthening scheme comprising of RC jacketing and FRP. Four large-scale RC beams were prepared, and three of them were strengthened. The first was strengthened by RC jacketing, the second by a combination of RC jacketing and flexural FRP, and the last by the combination of RC jacketing, flexural FRP and FRP ‘U wrap’ in the shear zones. The specimens were tested using the four-point bending test. The flexural behaviour was assessed in terms of the peak moment capacity, flexural stiffness, load-displacement response, crack pattern and failure modes. The test results confirmed that hybrid strengthening leads to strength gain and stiffness gains of 105% and 90% respectively, as compared with the unstrengthened beam. The efficacy of the theoretically predicted strengths against the test strengths is assessed.

Retrofitting Techniques of Columns: A Comprehensive Review of Methods and Materials

Column retrofitting is a critical aspect of structural maintenance and improvement. It ensures that existing structures remain safe, resilient, and adaptable to evolving needs, contributing to the longevity and sustainability of the built environment. It is essential to maintain or enhance the structural integrity of buildings and infrastructure, ensuring their continued safety, resilience, and functionality. In such cases, columns may not meet current safety codes, and it becomes essential to bring them up to contemporary standards and ensure compliance with building codes. The purpose of this paper is to provide a brief overview of the methods of retrofitting, like steel jacketing, wrapping, concrete jacketing and bracing. For these advanced methods materials used in retrofitting techniques and advanced methods for column retrofitting, as it addresses various challenges associated with existing structures. Key Words: Retrofitting, Steel Jacketing, CFRP Wrapping, concrete jacketing.

Concrete Strength Enhancement due to High‐Performance Fibre‐Reinforced Concrete Jacketing Solution

AbstractHigh‐Performance Fibre‐Reinforced Concrete (HPFRC) jacketing technique provides a sustainable solution to the constantly growing infrastructure degradation. This paper investigates the effect of HPFRC jacketing solution on strength enhancement of plain concrete. The experimental work included 23 samples, 15 of which were jacketed with HPFRC, and the remaining 8 were used to measure the unconfined strength. The key parameters were jacket thickness (25 mm, 35 mm, and 45 mm) and pre‐damage level (40% and 80%). The results show that jacketed columns exhibit a ductile behaviour. It is found that a 25 mm HPFRC jacket increases the compressive strength by 31%. Moreover, increasing the jacket thickness further enhances the compressive strength. However, the enhancement rate gradually decreases with increasing the jacket thickness. The results from sensor technology used on each concrete layer revealed that the lateral strain of jacketed concrete at a given axial strain was greater than that of unjacketed concrete, indicating an increased rate of dilation for the jacketed concrete. The results show that strengthening of existing columns at their mid‐service life (i.e., 40% pre‐damaged) is as effective as strengthening of new columns. The obtained knowledge suggests that HPFRC jacketing solution has a great potential to revolutionise infrastructure rehabilitation techniques.

Assessment of Composite Bars and FRP Panels for Seismic Bridge Decks

Seismic Strengthening offers a cost-effective and sustainable solution for constructing bridges in seismic zones. In these rehabilitation interventions, Fiber Reinforced Polymer (FRP) composites are often used instead of steel members due to their lightweight nature, high strength, and excellent corrosion resistance. Researchers are now focusing on creating innovative FRP-concrete hybrid structures. This study specifically investigates the numerical modeling of the response of a hybrid FRP-concrete jacket bridge pier subjected to quasi-static tests. The Finite Element Method (FEM) results demonstrated a significant correlation with the experimental response, particularly in terms of the load-displacement curve failure mode. Once the model was validated, various alternative designs were numerically tested to evaluate the impact of each model on the load-bearing capacity. These designs included altering the height of the CFRP sheet, adjusting the height and congestion of the CFRP bar, and comparing the performance of the concrete jacket with and without the CFRP sheet. After reinforcing the CFRP sheets and incorporating Near-Surface-Mounted (NSM)-CFRP bars, the reinforcement system, along with the new concrete jacket, effectively transferred the integrity of the broken pier area and maintained a constant load-bearing capacity for the bridge pier. However, when the CFRP sheet was added to the aforementioned system, the load capacity of the bridge pier increased by more than 60%. Therefore, it can be concluded that seismic enhancement techniques utilizing CFRP sheets and mounted NSM-CFRP bars are successful in enhancing the strength and resilience of the concrete bridge pier.

Effectiveness of composite jacket strengthening of reinforced concrete columns under eccentric load after fire exposure

This research presents a numerical study of the behavior of reinforced columns with a square cross section subjected to eccentric stress under the influence of fire. As a first step, the study examined the effects of exposing columns to fire with an increasing temperature up to 600°C for 60 minutes under eccentric loading conditions (e/b = 0, 0.1, 0.15, 0.20). As a second step, the columns were strengthened with a 100-mm concrete jacket and shirts supported by a steel structure consisting of vertical angles and horizontal spreaders to determine the effectiveness of the strengthening in increasing the resistance of these damaged columns. After the fire, this type of reinforcement is considered better than reinforcement with concrete shirts, reinforcement with carbon fiber-reinforced polymers, and others because of its advantages. There are many advantages to the ease and speed of implementation. The results showed that the columns that were repaired and strengthened after the fire with the steel structure casing led to a significant increase in resistance. It was found that the greater the thickness of the steel structure, the greater the resistance, and that the greater the eccentricity ratio, the lower the resistance as well as the collapse load.

Comparative evaluation of seismic performance and environmental impact of traditional and dissipation-based retrofitting solutions for precast structures

Seismic rehabilitation is crucial to extend the nominal service life and help reduce the seismic losses of reinforced concrete precast industrial buildings. Along with traditional retrofitting techniques, the latest decades are witnessing a growing use of innovative solutions, the latter including devices that can dissipate the ingoing seismic energy and are characterised by the replaceability after a seismic event. The goal of this work is to compare two retrofitting solutions, respectively of traditional and innovative type, in terms of structural performance enhancement and their own life cycle environmental impact. A case study single-storey precast industrial building was retrofitted firstly adopting a traditional solution with concrete jacketing of columns, and then using two innovative energy dissipation devices, namely a friction rotation damper for beam-to-column connections and a bracing system with dissipative sacrificial elements. A comparative analysis of the seismic response of the structure in its as-built and post-retrofit configurations was undertaken, subjecting three 3D numerical models created in OpenSees to nonlinear static and dynamic analyses in both the main directions. Subsequently, two environmental impact metrics were adopted to compare the life cycle environmental impact of both the traditional and innovative retrofitting solutions, confirming that the one encompassing the dissipation-based devices is expected to be more environment-friendly, under a life cycle perspective, than the traditional concrete jacketing.

Stress-strain behavior of columns confined with bamboo reinforced concrete jacket

ABSTRACT The need for retrofitting of building structures is generally caused by two cases: to repair damaged structures or to improve the structural performance of weak structures. The concrete jacket method is widely chosen to solve the problem due to the more economical and simple procedure compared to other methods. In this study, retrofitting using bamboo-reinforced concrete jacket (BRCJ) was applied on reinforced concrete columns. Bamboo was used to replace steel as the longitudinal and transverse reinforcements of the concrete jacket with the aim of finding an alternative for an environmentally friendly green material and a lower-cost manufacturing process compared to steel. The performance of the jacket was studied by investigating the confinement effectiveness that is influenced by initial column conditions, spacing of bamboo stirrups, and the slenderness of longitudinal reinforcement. The outcomes showed that the bamboo-reinforced concrete jackets were able to strengthen the columns up to 170% and 140% of the initial strength of the undamaged and damaged columns, respectively. The BRCJ is more effective on columns that are still at the pre-peak-strength stage. The confinement effectiveness is also largely affected by the bamboo stirrups spacing. By reducing the spacing of bamboo stirrups to about half that of steel stirrups, the ductility ratio of retrofitted columns increased up to 90% higher than the original columns. Further, the confinement effect of BRCJ can also be increased by increasing the slenderness ratio of bamboo longitudinal reinforcement. Finally, the stress–strain relationship for concrete columns retrofitted with bamboo-reinforced concrete jackets has been proposed which shows great agreement with the experimental data. Overall, BRCJ has shown promising results to be used to strengthen damaged or weak structures.

Rehabilitation of Severely Damaged RC Bridge Piers: Experimental and Numerical Investigation

ABSTRACT This study explored rehabilitation of severely damaged bridge pier models using reinforced concrete jacketing method adopting a plastic hinge relocation technique. The test specimens were tested under cyclic loading. The important seismic performance parameters were evaluated for the rehabilitated specimen. A 3D finite element model was simulated considering concrete-rebar interaction and jacket-pier interface shear. Calibration of the numerically simulated model was done by comparing with experimentally observed responses. Additionally, a parametric study was conducted to investigate the effect of shear connectors on performance of the rehabilitated test specimen.

Eccentric load behaviour of concrete columns retrofitted with engineered cementitious composite jackets via grooving method

The eccentric load behaviour of circular reinforced concrete columns strengthened with a novel engineered cementitious composite jackets reinforced with synthetic macro-fibres and polypropylene was investigated. Furthermore, an innovative method of interface treatment known as longitudinal grooving was used. Twelve test columns were cast, six of which were strengthened with 15 mm thick composite jackets, while three were strengthened with ultra-high-performance fibre-reinforced concrete jackets. In addition, three of the six columns strengthened with the composite jackets were confined with glass-fibre-reinforced polymer warps. The experimental results showed that both methods enhanced load-carrying capacity and energy dissipation with increasing load eccentricity. For example, the specimens strengthened with the composite jackets exhibited increases of 167% and 194% in load-carrying capacity, and enhancements of 92% and 53% at eccentricities of 30 and 60 mm, respectively. Finally, the previously reported model and different codes were used to validate the results, from which interaction diagrams were drawn. This showed a good agreement between experimental and predicted results.

Repairing and strengthening techniques of RC beams: a review

The purpose of this review is to present the techniques for strengthening or repairing of reinforced concrete-beams (RC). The concrete members, like RC beam are might be required to be strengthened to increase the internal strength capacity to resist additional external loads or repaired to increase the design’s structural rigidity and insulate the reinforcement from aggressive conditions. The experimental studies that related to the techniques of repairing and strengthening of RC beams using: external steel plates, fiber reinforced concrete (FRC), reinforced concrete (RC) jacketing, sprayed fiber reinforced polymer FRP, epoxy injection, mortar jackets, near-surface carbon fiber (SNSM-CFRP) strips, near-surface glass fiber (NSM-GFRP) rods, CFRP laminate and sheet; and adding an ultra high performance concrete (UHPC) layer. All the techniques that were discussed showed that there is an improvement in the general behavior of the beams that have been strengthened and repaired, as well as an increase in the maximum load and ductility.

Seismic behaviour assessment and rehabilitation of a masonry three‐arched bridge

AbstractMany existing historical masonry arch bridges used in the road and railway networks are still in service. However, most of them show a structural performance deficit due to several factors. This study deals with the seismic behavior assessment of an existing masonry three‐arched railway bridge through a nonlinear, non‐adaptive static analysis carried out by a three‐dimensional Finite Element model. Input data were collected from a variety of sources. The structural analysis showed a risk index that was not in compliance with the limit values suggested by current European Standards. In order to improve the structural reliability of the masonry arch railway bridge, a traditional structural rehabilitation was proposed and designed. The bottom faces of the arches and the piles of the masonry bridge were strengthened by reinforced concrete thin slabs and reinforced concrete jackets, respectively, all adequately connected to the existing structure by using steel bar connectors. Finally, a nonlinear analysis of the strengthened structure showed that the new risk index satisfied the seismic vulnerability verification. The proposed structural rehabilitation using traditional techniques appears to be a viable but not unique solution to improving structural reliability.

Time–frequency analysis of ultrasonic signals for quality assessment of bonded concrete

In accelerated bridge construction (ABC), 3D-printed concrete and structural retrofitting using concrete jacketing are used to reduce the onsite construction time. Both techniques involve bonded concrete, where a concrete layer is cast on the old substrate. As a result, the interfacial transition zone between these concrete layers is the weakest part of the structure. In this paper, a machine learning-based model is proposed to predict the bond strength between concrete layers from extracted ultrasonic features. Ultrasound tests provide the input parameters, and bi-surface shear test results are the targets for the machine learning model. To validate the method, laboratory testing is performed on 54 concrete specimens with different design mixtures and bond zone conditions. Variational Mode Decomposition (VMD) is applied to the ultrasonic signals, and three intrinsic mode functions (IMFs) are extracted from each signal leading to 21 independent features. Four machine learning algorithms are deployed, namely K-nearest-neighbors, support vector machine, random forest, and XGB regressors. XGB is found to be the most accurate model, and its hyperparameters are tuned to optimize the model performance. To improve the method, the features’ importance values are derived, and the most compelling features for training are identified, which are the third quartile and center frequency of the first IMF’s instantaneous frequency, and the center frequency and kurtosis of the second IMF’s instantaneous frequency. The resulting final model was a tuned XGBoost regression model that obtained an R-squared value of 95.5 percent taking the four features as input. For the four selected features, apparent clustering was found at a bond strength of 3 MPa, ensuring a reliable prediction of quality bond conditions. These results demonstrate the effectiveness of the proposed model in predicting the bi-surface shear strength of concrete layers based on ultrasonic testing.

Strengthening of Reinforced Concrete Columns Using Ultra-High Performance Fiber-Reinforced Concrete Jacket

The use of Ultra-High Performance Fiber Reinforced Concrete (UHPFRC) increased in the field of civil engineering throughout the last few decades. UHPFRC is being used considerably on a large scale in megastructure applications. High compressive and tensile strength permits reconstruction and optimization of the structural members. At the same time, its improved durability properties make it easier to extend the life of the design and can be used as thin layers, cladding, repairs, and column coverings. Although UHPC has an extremely high compressive strength, it exhibits very brittle fracture behavior compared to normal strength concrete (NSC). Since the ductility and fracture toughness of UHPC can be enhanced by adding fibers, the addition of fibers to production adds innovative features to UHPFRC structures and opens up new application areas for UHPFRC. The aim of this study is to investigate the axial behavior of square reinforced concrete (RC) columns strengthened with UHPFRC jackets. Nineteen specimens were cast (1000 mm in height and a cross-sectional area of 150 × 150 mm, whose interface treatment methods were prepared through vertical grooving (VG), horizontal grooving (HG), and without grooving (NG), with the jacket thickness (20 mm and 40 mm) and the number of strengthened sides of the column (two, three, and four sides). The results show a brittle failure for all strengthened specimens. The UHPFRC-reinforced RC columns with vertical grooving (VG) showed a higher ultimate load capacity compared to the columns with horizontal grooving (HG) and the columns without grooving (NG). The horizontal grooving (HG) gives a better result than the jacket without grooving (NG) and increases the cohesion area between the jacket and the column for two and three of the RC columns’ strengthened sides. But, in the case of strengthening the columns on four sides, the effect of confining the jacket to the column appears, and the grooving causes weakness in the body of the original column so that the jacket without grooving (NG) gives a better result than the jacket with horizontal grooving (HG).

Effects of chloride salt erosion and freeze–thaw cycle on interface shear behavior between ordinary concrete and self-compacting concrete

Self-compacting concrete (SCC) has been widely used for concrete jacketing to strengthen RC structures due to its high workability, fluidity, and segregation resistance. In this study, a test was carried out to study the effects of substrate curing including chloride salt erosion and the freeze–thaw cycle on the interface shear strength between ordinary concrete and the SCC. Eighty-four Z-type specimens were designed and tested through direct shear experiments, and the influence of interface treatment (implanting steel bar and cutting groove), concrete type, and substrate curing on the interface shear strength were analyzed. Four calculation models of interface shear strength based on different codes are compared, the applicability of these models is also analyzed. The results show that: For close the substrate concrete and the SCC strength, the effect of chloride salt erosion and freeze–thaw cycle will cause a slight decrease in the interface shear strength compared with the specimen that substrate is not cured, the influence of chloride ion erosion and freeze–thaw cycle on the degeneration of interface shear strength for specimen with implanting steel bar is not more obviously than specimen with cutting groove. Any single code model can not accurately predict the interface shear strength of all specimens with different interface treatments and substrate curing. The fib model can accurately predict interface shear strength of specimens which the average compressive strength of old and new concrete is less than 40 MPa and the substrate is not cured. Whether the substrate is cured or not, EC2 and CSA A23.3–14 models can quite accurately predict the interface shear strength of specimens with an implanting steel bar, but for specimens with cutting groove, the modified AASHTO model can accurately predict the interface shear strength. Except modified AASHTO model, the factor considering the effect of interface treatment should be taken into account when using fib, EC2 and CSA A23.3–14 models to calculate the interface shear strength.

SEISMIC RETROFIT OF SUBSTANDARD RC BRIDGES USING CONTEMPORARY MITIGATION MEASURES

As essential infrastructure components, existing substandard bridges may cause significant economic losses at the urban scale as they are prone to different damage modes under seismic excitations. Due to the large number of existing RC bridges in earthquake-prone regions and the continuous updates in seismic design criteria, there is increasing interest in developing effective seismic retrofit techniques for enhancing the performance of these structures. This study thus investigates the effectiveness of contemporary retrofit measures for upgrading the seismic performance of RC bridges, namely ultra-high-performance concrete (UHPC) jackets and self-centering energy dissipating (SCED) braces. Detailed fiber-based numerical models are developed for scaled RC bridge substructures retrofitted with the adopted mitigation measures. The hysteretic behavior of the bridge substructures from quasi-static cyclic loading experiments conducted in previous studies is utilized to verify the developed fiber-based models. The validated modeling approaches of retrofit strategies are then applied to an old benchmark bridge located in a medium seismicity zone. The inelastic response of the benchmark bridge substructure before and after the retrofit with different mitigation measures is assessed using the verified fiber-based numerical models. The results demonstrate that the retrofit measures increased the lateral strength of the bridge bent by 37.5%. Also, 10% improved ductility was observed in the UHPC retrofitted bent. This performance assessment study enabled the selection of effective measures to mitigate the vulnerability of substandard bridge members to ensure their post-earthquake functionality.