Shear Resistance Capacity Research Articles

Study on the composition and properties of EME-SBS-Nano ZnO high modulus asphalt material

The objective of this research is to address the rut problems in asphalt pavements and to resist the permanent plastic deformation with the increasing heavy traffic loads. In this paper, a new type materials of high modulus asphalt was developed by incorporating styrene–butadiene–styrene (SBS) and zinc oxide nanoparticles (nano ZnO) with an (EME)-type high modulus modifier, guided by the synergistic effects and the preparation methods of High-speed shear. The basic road performance, mechanical response and thermal stability of the new high modulus asphalt materials were analysed through basic physical indicator tests, dynamic shear rheometer tests, thermogravimetric analysis (TGA), the time–temperature superposition principle, the Refutas model, and the Christensen-Andersen-Marasteanu model. The optimal results demonstrate that the optimal blend ratio of the developed asphalt is 12% EME/8% SBS/1.5% ZnO. Under this composition, the road performance indicator values of softening point, penetration and ductility of the modified asphalt met the standard requirements. The dynamic shear rheometer tests demonstrates that the inclusion of SBS and nano ZnO considerably enhanced the shear resistance and recovery deformation capacity of EME, effectively improving the high-temperature deformation resistance of asphalt. Furthermore,the Refutas and the Christensen-Andersen-Marasteanu model fitting results showed that adding SBS and nano ZnO considerably improved the temperature sensitivity of the EME types high modulus modified asphalt and exhibiting low frequency sensitivity. Compared to PR Module-type high modulus modifier(PRM),TGA reveals that the maximum thermal weight loss of EME-SBS-ZnO decreased by 3.5441%, indicating better thermal stability and the major character of SBS,EME and asphalt is physical reaction. Moreover, EME-nano ZnO-SBS high modulus asphalt at 64 °C shows Jnr-diff = 9.5% and passes the "E" extreme traffic grade. Additionally, its cost is 4.67% lower than that of the PRM high modulus modified asphalt, presenting considerable economic benefits.

Performance of channel shear connectors in steel frame with reinforced concrete infill walls

To examine the mechanical properties of channel shear connectors employed in steel frame with reinforced concrete infill wall (SRCW) structures, the improved push-out tests were performed on three specimens of channel shear connectors subjected to the monotonic and cyclic loading. This study investigated the influences of loading protocol and concrete strength on the mechanical behavior of channel shear connectors. After the refined finite element (EF) models of channel shear connectors were validated based on the push-out tests, a systematical parametric analysis was conducted to evaluate the effects of RC infill wall thickness, concrete strength, and channel dimensions on its shear strength of the channel shear connectors. In addition, this study also compared the accuracy of the CSA S16, AISC 360 and GB50017 design code in predicting the shear capacity of channel shear connectors in SRCW structures. The experimental results and parametric studies indicated that the current design equations inaccurately evaluate the shear capacity of channel shear connectors used in SRCW structures. Consequently, an alternative equation was developed to estimate the shear-resistant capacity of channel shear connectors in SRCW structures, which provided the desirable calculation precision for engineering design.

Experimental and Theoretical Study on the Interface Mechanical Performance of Aluminum–Timber Composite Connections

The interface mechanical performance between aluminum alloy and timber is the key to ensure that the two work together. In this study, 11 group connection performance tests were carried out to investigate the influence of connection type (shear bolt connection, epoxy resin adhesive connection, and mixed connection), number and spacing of bolts, thickness, and length (the area of incidence of the adhesive in the structure) of epoxy resin adhesive on the interface shear-resistant capacity of aluminum–timber composite connections. The shear performance of the three kinds of connections were studied via finite element analysis, and the calculation formula for interface shear-resistant capacity of the aluminum–timber composite connection was proposed based on the bond-slip mechanism of adhesive. The analysis results indicate that the mixed connection can avoid the brittle failure characteristics of the shear bolt connection and the epoxy resin adhesive connection, and the shear-resistant capacity is increased by 45.6% and 14.7%, respectively. The results of the calculation formula for interface shear-resistant capacity are in good agreement with the experimental results, indicating that it is suitable for the aluminum–timber composite connection.

Durability of Fe-SMA/steel single-lap joints exposed to hygrothermal environments

Due to the adverse impact of hygrothermal environments and fatigue load, the performance degradation of existing steel structures necessitates repairs to extend their service life. Structures retrofitted by bonding iron-based shape memory alloy (Fe-SMA) have been demonstrated as an active non-destructive repair method. Nevertheless, the deterioration of the adhesives triggered by hygrothermal environments is a crucial challenge in its practical reinforcement applications. In this study, 54 Fe-SMA/steel single-lap joints (SLJs) are aged in 55°C and 98 % relative humidity environments for 30, 60 and 110 days, and tested under shear loads. The long-term performance, failure patterns, load-displacement responses and shear-resistance capacity of the SLJs are investigated, considering the essential parameters of aging time, overlap length and adhesive types. The experimental results exhibit that the failure patterns of aged Fe-SMA/steel SLJs depend highly on the adhesive types. The shear-resistance capacity of Fe-SMA/steel SLJs decreases dramatically with the prolongation of aging time. After 110 days of aging, the shear-resistance capacity of type-C, type-S and type-P SLJs decreases by about 14 %, 39 % and 49 %, respectively. When the overlap length increases from 50 mm to 150 mm, the shear-resistance capacity of type-C, type-S and type-P Fe-SMA/steel SLJs improves by 21 %, 39 % and 22 %, respectively, increasing the overlap length can safeguard the optimal functionality and long-term performance of the retrofitted steel structures. While the environments are relatively aggressive, it is recommended to use type-C adhesive to obtain the satisfactory serviceability of the retrofitted steel structures. The experimental achievements are significant for repairing deteriorated steel infrastructures by bonding Fe-SMA, guaranteeing the long-term performance and normal-use safety of structural reinforcement design, and reducing carbon emissions due to the avoidance of reconstruction.

Shear strength model of FRP-reinforced concrete beams without shear reinforcement

The current design codes for evaluating the shear strength of concrete beams reinforced with fiber-reinforced polymer (FRP) bars predominantly rely on a semi-empirical approach through test data calibration without a robust theoretical background. This approach may lead to either overestimation or underestimation, resulting in significant scattering in strength predictions. This study proposed a modified approach to enhance the existing unified shear-strength model developed for steel-reinforced concrete (RC) beams based on the compression zone failure mechanism, for predicting the shear strength of FRP-RC beams without shear reinforcement. The proposed model integrates strain and stress approaches, accounting for the distinctive characteristics associated with FRP reinforcement. Additionally, the overall shear resistance capacity of the FRP-RC beam is considered as the sum of contributions from the intact concrete of the compression zone and the aggregate interlock mechanism. The reliability of the proposed model is verified by comparing its predictions with a comprehensive database comprising 264 FRP-RC beam specimens without shear reinforcement reported by 41 research groups. Furthermore, the accuracy of the proposed model was assessed through a comparative analysis with existing evaluation methods, encompassing machine learning-based models, empirical models, theoretical models, and design codes. The results indicate that the proposed model satisfactorily predicts the shear strength of FRP-RC beams within a wide range of design parameters. In comparison with machine learning-based models, the proposed theoretical model exhibits a similar level of accuracy in terms of the mean shear strength ratio and coefficient of determination (R2) values but with less scattering, indicated by lower coefficient of variation (COV) and root mean square error (RMSE) values. In addition, the proposed model outperforms existing empirical and theoretical models, as well as current design codes, by significantly enhancing prediction accuracy, demonstrated by lower COV, RMSE, and higher R2 values. Finally, a parametric study was conducted to investigate the effects of the key parameters on the shear strength of FRP-RC beams using both the proposed model and representative existing evaluation methods.

Evaluation of Hysteretic Performance of Horizontally Placed Corrugated Steel Plate Shear Walls with Vertical Stiffeners

Corrugated steel plate shear walls (CSPSWs) have been widely utilized as lateral-resistant and energy-dissipating components in multistory and high-rise buildings. To improve their buckling stability, shear resistance, and energy-dissipating capacity, stiffeners were added to the CSPSW, forming stiffened CSPSWs (SCSPSWs). Evaluating the hysteretic performances of SCSPSWs is crucial for guiding seismic design in engineering practice. In this paper, the dissipated energy values of the SCSPSWs with different parameters were calculated. Based on the obtained dissipated energy values, the elastoplastic design theory of stiffeners was established, and the evaluation of the hysteretic performance of the SCSPSWs was provided. Firstly, a finite element (FE) model for analyzing the hysteretic performance of the SCSPSWs was developed and validated against hysteretic tests of the CSPSW conducted by the authors previously. Subsequently, using the validated FE model, approximately 81 examples of SCSPSWs subjected to cyclic loads were analyzed. Hysteretic curves, skeleton curves, secant stiffness, stress distribution, and out-of-plane displacement were obtained and examined. Results indicate that increasing the bending rigidity of the vertical stiffeners and the thickness of the corrugated steel plates, as well as reducing the aspect ratio of the corrugated steel plates, is beneficial for enhancing the load-carrying capacity, stiffness, and energy dissipation capacity of the SCSPSWs. Finally, the transition rigidity ratio μ0,h was proposed to describe the hysteretic performances. When the rigidity ratio is μ = 50, dissipated energy values of the SCSPSW could achieve 95% of the corresponding maximum dissipated energy. In engineering practice, hence, it is recommended to use stiffeners with a rigidity ratio of μ ≥ μ0,h = 50 to ensure desirable energy-dissipating capacity in the SCSPSW.

Experimental Study on the Flexural and Shear Performance of Concrete Beams Strengthened with Prestressed CFRP Tendons

To investigate the influence of external prestressing with carbon fiber-reinforced polymer (CFRP) tendons on the flexural and shear performance of reinforced concrete beams, a total of six simply supported beams with a length of 3.5 m and two two-span continuous beams with a length of 7 m were studied. The influences of the prestressing level of CFRP tendons, the pattern of straight-line and flexural reinforcement of externally prestressed CFRP tendons, and the existence of initial cracks in the beams on the flexural bearing capacity of the reinforced beams were explored through modeling tests. The calculating equation for anticipating the ultimate flexural bearing capacity of concrete beams reinforced with externally prestressed CFRP tendons was modified based on the test results. The findings indicate that the flexural bearing capacity of the test beams was significantly enhanced through both flexural and straight-line reinforcement. Specifically, the ultimate flexural bearing capacity of the simply supported beams exhibited improvements of approximately 160% and 170%, respectively, whereas the ultimate flexural bearing capacity of the continuous beams was enhanced by approximately 113% through the reinforcement of flexural arrangement. Additionally, the shear resistance capacity of the concrete beams was notably improved through the flexural arrangement reinforcement, and the shear resistance capacity of the beams exhibited a substantial increase as the prestressing level of the CFRP tendons increased. The flexural moments in the vicinity of the support point of the reinforced beam exhibited an increase ranging from 41.7% to 112.5% when the stirrup strains started to escalate rapidly. Additionally, the rigidity of the test beams showed a close correlation with both the prestressing level and the existence of initial cracks.

Continuation of a cleaning process: Application of MNBs-coagulation process to mitigate ultrafiltration membrane fouling

The MNBs-coagulation process as a novel and cleaning enhanced coagulation process has been demonstrated to enhance the removal efficiency of hydrophilic organics. In this study, while continuing the concept of cleaning production, the MNBs-coagulation process was first applied to the ultrafiltration process and was expected to alleviate the ultrafiltration membrane fouling. This study investigated the effect of the involvement of MNBs in coagulation-ultrafiltration process (the MC-UF process) on the fouling behaviour of ultrafiltration membrane based on the calculation of membrane resistance distribution and the fitting of membrane fouling model. In addition, the NOM removal efficiency, floc characteristics analysis and membrane hydrophilicity analysis were used to illustrate the mechanism of mitigating ultrafiltration mebrane fouling by the MC-UF process. The experimental results showed that the involvement of MNBs in the coagulation-ultrafiltration process was able to reduce the irreversible fouling and TMP by 43.1 % and 41.6 % respectively. This phenomenon could be attributed to the involvement of MNBs in the coagulation process to improve the removal efficiency of hydrophilic organics and to enhance the characteristics of flocs, thus reducing the possibility of hydrophilic organics and broken flocs entering and blocking the membrane pores. In addition, the FT-IR spectral changes before and after the floc breakage were analyzed by 2D-COS technique in this study, and it was found for the first time that the participation of MNBs in the coagulation process could change the sequence of functional group transformation within the floc, and promote the generation of hydrogen bonds between flocs by hindering the generation of hydroxyl groups (-OH), and improve the shear resistance and regrowth capacity of flocs while reducing the possibility of broken flocs entering and blocking membrane pores. In summary, the MC-UF process proposed in this study can significantly mitigate ultrafiltration membrane fouling while meeting cleaning production, providing theoretical support for the application of the process to practical engineering.

Experimental and numerical investigation into hysteretic performance of orthogonal double corrugated steel plate shear wall

The orthogonal double corrugated steel plate shear wall (ODC-SPSW) is comprised of two identical corrugated plates that are arranged orthogonally and interconnected through high-strength bolts located at the valleys of the corrugations. Due to the strong axis of one corrugated plate coinciding with the weak axis of the other corrugated plate, the flexural rigidity of each plate can be significantly enhanced in its weak axis, thereby improving its shear resistance. The ODC-SPSW has itself boundary elements in two side and connected only with frame beams at its top and bottom, leading to conveniently moving within the frame. This paper presents experimental and numerical analyses of the shear resistance and the hysteretic performance of ODC-SPSW. Two experimental specimens subjected to cyclic loading were tested, and accordingly finite element (FE) simulations were conducted, both reaching an excellent agreement. Firstly, the test results of two ODC-SPSW specimens under cyclic loading are reported and analyzed. Second, FE models are established to simulate the hysteretic energy-dissipation performance of the test specimens. The numerical results from FE Model agree well with the test results, thus validating the FE models. Moreover, a parametric study was conducted using the validated FE model through changing various geometrical parameters, such as aspect ratio, bolt number and arrangement, corrugation depth, corrugated steel plate thickness, boundary element dimensions of the ODC-SPSWs. It is found that these parameters affect significantly the ultimate shear resistance and hysteretic energy-dissipation capacity of the ODC-SPSW. The numerical result obtained indicated the dimensions of the boundary elements have little effect on the shear resistance and hysteresis performance of the ODC-SPSWs. Finally, some design recommendations are concluded which can provide valuable references for the practical design of ODC-SPSWs.

In-plane seismic behaviour of urm and confined masonry built from vertically perforated blocks and polyurethane glue

Masonry construction using vertically perforated clay blocks with large holes and polyurethane glue is a modern technology designed primarily for low thermal losses. This study aims to evaluate the in-plane seismic behaviour of masonry constructed using unreinforced masonry (URM) and confined masonry construction technology. The experimental methods consist of triplet tests on joints and cyclic shear compression tests on eight full-scale walls, six of which are URM and two of which are confined masonry. Tests on URM walls are performed at three different levels of compressive stress to analyse the effect of compressive stress on the seismic response. The effects of compressive stress on shear resistance and drift capacity are quantified and compared with results from a database. The performance of the tested walls is comparable to what is expected from modern URM walls. Two confined masonry walls were of the same dimensions as the URM walls and are evaluated at the highest compressive stress level used in tests of URM walls. The results indicate that confined masonry should be the preferred technology for seismic regions because of its higher strength, displacement capacity, ductility, and energy dissipation.

Study on Flexural and Shear Behavior of UHPC Rhombus-Strip-Shaped Joint

Accelerated bridge construction (ABC) has many advantages for bridge construction in modern society. While for ABC, the post-cast joint is always the weakest and most critical part. This paper presents a UHPC rhombus-strip-shaped (RSS) joint suitable for ABC. Several model tests were carried out to verify its resistance to flexural and shear. First, large-scale model tests are advanced to confirm its flexural properties. The results show that densified and welded joint interface rebars can significantly improve the ultimate bearing capacity and durability-based cracking stress of the RSS joint beams, and the ultimate bearing capacity can reach 90% of the complete beam. Then the shear-resistance tests were carried out. The results show that the UHPC RSS joint beam has excellent bending-shear mechanical properties and better ductility. Lastly, the ultimate flexural bearing capacity and shear-resistance capacity calculation methods were obtained.

Study on the electronic structures, mechanical properties, and lithium-ion migration of Mo-N co-doped LiFePO4 by first-principles

This article uses first principles to calculate the mechanical stability, electronic structure, and electrochemical performance of Mo-N co-doped LiFePO4. The formation energy of Mo-N co-doped LiFePO4 indicates excellent thermodynamic stability. Electron density of states and effective electron mass calculations demonstrate that co-doping can enhance the electrical conductivity of the system. The de-lithium calculations show that doping the material with Mo-N enhances its cyclic stability. Elastic constant calculations demonstrate that the dopants can enhance the shear resistance and de-lithium capacity of LiFePO4. Additionally, investigations on the material's anisotropy have revealed that Mo-N co-doping tends to promote isotropy in the material. The decrease in the migration barrier of the doped system indicates that co-doping increases the migration rate of lithium ions, thereby enhancing the rate performance of the material.

Numerical investigation of the punching shear resistance capacity of reinforced concrete slab

The article studies the punching shear capacity of reinforced concrete slabs by simulation method. Based on the Concrete Damage Plasticity (CDP) constitute model, the simulation model is established in the Abaqus software. The simulation model was verified by the comparison of punching shear tests. The parametric studies were implemented to investigate the effect of concrete and steel strength on the punching shear resistance capacity of the reinforced concrete slab. The punching shear resistance capacity of reinforced concrete slab was also calculated by the formulas proposed by available standards. Obtained results show that increasing concrete strength leads to a significant increment in the punching shear resistance capacity of slabs while the influence of steel strength is slight.

Shear resistance strengthening of novel castellated key with embedded steel plates for dry joints in precast bridges

The shear performance of the precast segment concrete bridge depends largely on the shear resistance of joints between adjacent segments. However, the current joint structures have the limitation of shear resistance strengthening and the inconvenience of construction. To improve the shear capacity of the joints and achieve quick construction, a novel castellated shear key incorporating embedded steel plates is proposed. A total of fifteen single-keyed dry joints were designed, including two reference joints with a plain concrete key and a reinforced key and thirteen novel keys with embedded steel plates. Monotonic push-off tests of joints with or without shear keys were carried out. The influence of design parameters of the novel shear key, including height-to-thickness ratio, strength, steel ratio of the steel plates and bonding methods between concrete and steel plates on the shear performance of the joints were investigated comprehensively. The results indicated that the reinforcement of the shear capacity of the joints with the novel keys was 8.5%–33.9% higher than that of the joints with plain concrete keys due to the yielding of the steel plates. As expected, the embedded steel plates in shear keys could reach a shear-yielding state when the height-to-thickness ratio was larger than 25 or the yield strength of steel plates was lower than 355 MPa. A prediction formula of shear resistance capacity for the joints with novel shear keys was proposed considering the contribution of concrete and steel plates. It showed good prediction accuracy with an average value of 0.98 for the ratio of predicted to experimental values.

Ferrocement, Carbon, and Polypropylene Fibers for Strengthening Masonry Shear Walls.

This paper describes an experimental investigation into the feasibility of using ferrocement jacketing, polypropylene fibers, and carbon fiber reinforced polymer sheets (CFRP) to enhance the shear resistance of unreinforced brick masonry. The study involved testing 12 wall panels in diagonal compression, three of which were strengthened using each of the above-mentioned techniques. The results showed that all three strengthening techniques led to a significant improvement in the shear resistance and deformation capacity of the unreinforced walls. Furthermore, the results showed that the strengthened walls exhibited a significant improvement in shear resistance and deformation capacity by a factor of 3.3-4.7 and 3.7-6.8, respectively. These findings suggest that ferrocement jacketing is a viable and highly effective method for strengthening masonry structures. Test results can assist in the decision-making process to identify the most suitable design and retrofitting solution, which could indicate that not only new materials, but also traditional methods and materials (ferrocement) could be interesting and effective, also considering their lower initial cost.

Shear-resistant capacity and design of orthogonal double-corrugated-plate shear walls

The orthogonal double corrugated plate shear wall (ODCPSW) is composed of the wall element and the vertical edge members. The wall element consists of two identical corrugated plates installed in an orthogonal pattern, and high-strength bolts are adopted to directly connect them at the corrugation valley regions. The vertical edge members may be installed in two sides of the ODCPSW by employing single steel plates. Since the strong axis of one corrugated plate coincides with the weak axis of the other corrugated plate, the flexural rigidity of each corrugated plate in its weak axis can be improved significantly, thus enhancing its shear resistance. An ODCPSW is connected with frame beams by T-shaped fishplates, leading to characteristic of a flexible layout, standardized design and production, and assembly construction. This paper studies the shear-resistant capacity of the ODCPSW theoretically and numerically to obtain its strength design method. First, the orthogonal double corrugated plates are transformed into orthogonal plates, and accordingly the rigidity constants, including flexural rigidity constants (Dx=Dy) and torsional rigidity constants (H), are defined and introduced as basic feature in investigating its behaviors. Then, the formula for predicting the shear elastic buckling load of ODCPSW is obtained by fitting its elastic buckling coefficient form the elastic buckling analysis results of a large number of examples. Then the normalized height-to-thickness ratio, as a key design parameter, is established from the shear elastic buckling load. Finally, the shear-resistant capacity of the ODCPSWs is investigated by using numerical examples. The shear-resistant capacity of the ODCPSW may be considered to be equal to the superposition of that of the ODCPSW with two vertical sides simply supported and that of the moment-resistant frame formed by two edge members.

Experimental Study of Bearing Capacity of Steel Frame with Portal Steel Plate Shear Wall Member

The steel frame with portal steel plate shear wall unit presented here is a new steel structure by assembling the portal steel plate shear wall into the steel frame through bolt connection. For study of shear resistance and bearing capacity of the structure, it is necessary to conduct experimental research. Three frame specimens are made here, and two geometric shapes and the case of setting stiffeners and not setting stiffeners are considered respectively. The concentrated lateral load is applied in the test and displacements and strain were measured. The results show that the setting of the shear wall element has an obvious effect on improving the lateral stiffness of the steel frame, and the failure also shows obvious plastic deformation characteristics. It is also seen that the connection has no evident failure or deformation, which means the connection construction is effective.

A survey of shear strength behavior of high content fly ash reinforced concrete beams

Fly ash (FA) is a significant industrial byproduct that causes environmental problems. It is utilized in a range of application fields, including as the filling of down regions, mine filling, bricks, and the partial replacement of cement in concrete building, in an effort to lessen the environmental concerns it poses. Numerous studies have been conducted to determine the best way to use FA as a substitute for cement and fine aggregate in concrete and how it affects the mechanical and structural performance of modified concrete. In this view, the current study provides an overview of prior experimental outcomes on the behavior of high content fly ash (HCFA) reinforced concrete (RC) beams under shear. The effect of partially replacing cement in concrete with HCFA ranging from 0% to 70% on several factors pertaining to beam resistance in shear, such as the ratio between shear span and depth of the beam, concrete mix proportions, and concrete reinforcement, has been evaluated. The results on the shear resistance capacity of RC beams under shear at first crack and failure load, as well as deflection at ultimate load, have been presented and discussed. According to the available test results, up to 50% FA can be employed efficiently in concrete construction with no substantial reduction in shear strength. A review of the literature reveals that there is limited data on the influence of HCFA on the shear strength of beams, and more experimental studies are required to understand the shear performance of reinforced concrete members containing FA at the ultimate load and the resulting failure criteria.

Shear behavior of fiber reinforced concrete beams with high fly ash content

The shear behavior of Fiber Reinforced Concrete (FRC) beams with high Fly Ash (FA) content is investigated experimentally. Despite greater understanding of FRC shear behavior for the design of structural elements such as beams, the practicality of FRC with a high FA content has yet to be determined. Despite the fact that substantial study has been undertaken to establish the optimal usage of FA as a cement and fine aggregate replacement in concrete while investigating the shear behavior of conventional concrete, only a few studies have focused on the influence of FA in the FRC on concrete's shear behavior. The findings of shear tests performed on the FRC concrete beams of dimension 900 mm long by 80 mm wide by 120 mm high containing a high FA content up to 50 % are presented in this study. This study's principal goal is to investigate the impact of factors such as FA replacement level with fine aggregate and fiber volume on the shear behavior of concrete beams. Concrete mix with different combinations of 50 % FA by weight, as a replacement for fine aggregate, and steel fiber 1 % by volume is investigated. A four-point loading setup was used to test each of the beams. The results on FRC shear resistance capacity at failure load, as well as the effect of fiber volume and high FA content on ultimate load, have been presented and discussed. Mid-span deflection and crack patterns are also investigated during testing. The test results reveal that FRC overperforms in the presence of FA at a level of 50 % fine aggregate replacement with FA. Fibers, as expected, delayed crack formation and significantly reduced their width. As a result, it can be concluded that 50 % fine aggregate replacement with FA can be used effectively in concrete construction with no significant loss in shear strength, both in the presence and absence of steel fibers.

Effects of metakaolin on the shear capacity of EBFRP RC beams: An experimental and numerical investigation

The main aim of this study is to find the shear resistance capacity of the fiber-reinforced polymer beam with metakaolin. The RC beams used in this work were prepared with the replacement of cement by 35 % metakaolin. The major objective of this study is to understand the overall behavior of metakaolin-based reinforced concrete beams strengthened using fiber-reinforced polymer (FRP) composites. First, several trials were prepared with different dosages of metakaolin, biochar, and eggshell powder for achieving a target cubic compressive strength of 30 MPa. From the developed optimized mix, 12 RC beams were cast and strengthened with different configurations of carbon FRP wrapping. Test results revealed that the RC beam developed with metakaolin and strengthened with full wrapping (CFRP-FW) showed better overall performance in terms of peak strength and ductility. In addition to the experimental program, a detailed non-linear finite element (FE) analysis was performed using the commercial software ABAQUS. The predictions from the FE analyses matched well with the experimental results in terms of peak shear strength and failure patterns. The validated FE model was used for performing a detailed parametric analysis aiming to determine optimum design outputs for external bonding strengthening of metakaolin-based RC beams under shear.