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The need for repair and rehabilitation is a crucial issue today in order to maintain a safe and efficient transportation network. One of the most recent innovative composite materials that has been proposed to the market is a fabric reinforced cementitious matrix (FRCM) strengthening system. This system consists of two components: a structural rein...
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Context 1
... load-displacement curves are shown in Fig. 7. The experimental results of the ultimate load capacity were compared with predicted results using ACI methodologies, as presented in Table 4. The results indicated that the beam spec- imens failed at approximately twice the estimated load using ACI 318 (ACI 2014) and ACI 549 (ACI 2013). ...
Context 2
... strain reading was between 0.01 and 0.025 mm=mm (in:=in:) in the FRCM system. The percentage increase in the strengthened beam specimens' ultimate load capacity compared to the control beam (B1-0) is pre- sented in Table 4. The strengthened beam specimens with one ply of the FRCM system exhibited a 13, 36, and 15% increase in the ultimate load capacity. ...
Similar publications
This paper presented the results of an experimental study of the behaviour of flexural beams strengthened with the glass fiber reinforced polymer (GFRP-S). This research was carried out to determine the effect of fatigue loads on the flexural capacity of reinforced concrete beams. The specimens were rectangular with a dimension of 150 mm in width,...
Citations
... This shift aims to overcome the challenges posed by epoxies and enhance the overall reinforcement technique [12] [14]. However, the integration of fiber sheets into an inorganic matrix, such as mortar, has presented difficulties, primarily attributed to the granule size of the mortar [15]. Even finely textured mortar struggles to impregnate fiber bundles in the same manner as resins [16]. ...
Renovation, refurbishment, restoration, and retrofitting of existing structures have grown more challenging issues for the construction profession. Construction buildings are susceptible to damage at the time of the earthquake and need strengthening to enhance their strength, stiffness, and ductility. Fabric-reinforced cementitious matrix (FRCM) techniques have been recently introduced to the construction sector as a feasible solution for fiber-reinforced polymers (FRP) in strengthening application. FRCM composed of high strength fabric grids with cement-based material serve as a binder for FRCM matrices. The binder employed for FRCM composed of cement-based mortar along with polymers are added to improve the bond strength properties. The cementitious matrix utilized in FRCM has superior thermal resistance and better compatibility with the concrete surface. The utilization of FRCM matrix for upgrading and restoring the concrete members is gaining more prominence as a replacement to FRP. This work conducts a thorough analysis of the application of FRCM techniques to concrete structural members like beams, columns, slabs, and beam-column joints. This paper primarily aims to present the FRCM process on structural members and to discuss the flexural, shear, and load carrying FRCM materials that are used in the field.
... The application of GFRCM jackets has shown to improve the axial strain and confined compressive strength and decreased the strength degradation of transverse steel bars in columns with different reinforcement ratios and cross-section geometries. Meanwhile, the fatigue performance of FRCMstrengthened RC beams has been investigated [21,22]. The behavior of corrosion-damaged RC beams strengthened in terms of both shear and flexure by FRCM composites has been analyzed [23,24]. ...
The performance of a new fiber-reinforced cementitious matrix (FRCM) system developed using custom-designed mortar and fabrics is investigated in this study. The behavior of this system is evaluated in terms of both the flexural and shear strengthening of reinforced concrete beams. Eight beams are designed to assess the effectiveness of the FRCM system in terms of flexural strengthening, and four specimens are designed to investigate their shear behavior. The parameters investigated for flexural strengthening are the number of layers, span/depth ratio, and the strengthening method. Unlike previous studies, custom fabrics with similar axial stiffness are used in all strengthening methods in this study. In the shear-strengthened specimens, the effects of the span/depth ratio and strengthening system type (fiber-reinforced polymer (FRP) or FRCM) are investigated. The proposed FRCM system exhibits desirable flexural and shear strengthening for enhancing the load capacity, provides sufficient bonding with the substrate, and prevents premature failure modes. Considering the similar axial stiffness of fabrics used in both FRCM and FRP systems and the higher load capacity of specimens strengthened by the former, cement-based mortar performs better than epoxy.
... Since the last fifteen years, both new prefabricated structural elements and the repair and rehabilitation sector have increased their use of textile-reinforced mortar composites [54][55][56][57][58]. Since there are so many different kinds of textile and mortar matrices available, the textile-reinforced mortars have a broad range of mechanical features [59][60][61][62][63][64]. The most common non-metallic materials utilized in textiles include carbon [65][66][67][68][69], alkali-resistant glass [70][71][72], basalt [73][74][75][76], polyphenylene bezobisoxazole (PBO) [77,78], and other natural fibers, like hemp [79][80][81][82], flax [83,84], and sisal. These materials could be coated, dried, or impregnated into the matrix. ...
Construction repairs have used fiber-reinforced cement mortar (FRCM). Concrete and FRCM bond strength usually outweigh mechanical criteria. Nevertheless, testing complex bonds like the FRCM and concrete bond takes time, money, and errors. This study employed fuzzy logic (FL) based on the adaptive neuro-fuzzy inference system (ANFIS) to simplify and reliably estimate the FRCM-to-concrete bond strength (CBS) by modeling complicated and non-linear systems computationally efficiently. The models take six inputs: concrete splice length, stirrup cross-sectional area to spacing, longitudinal tension bar area to effective cross section, compressive strength, relative rib area, and minimum concrete cover. The model outputs concrete steel bar bond strength. The FLANFIS model predicts FRCM-to-CBS using the tensile testing results of the 10 specimens (5 concrete and 5 FRCM). Data instruct the model and measure its precision. This article defines the ANFIS-based FRCM-to-CBS. This research will employ 5 concrete specimens and 5 FRCM specimens, totaling 0.05 m^3 of concrete and FRCM mix. 0.25 kg of adhesive bonds the sample. Grip, control, and data gathering systems are employed with a 1 kN tensile testing equipment. This research comprises preparing concrete and FRCM specimens, bonding with adhesive, and tensile testing. The FL-ANFIS model predicts FRCM-to-CBS with a high coefficient of determination (R2) of 0.995 and a strong correlation coefficient (r) of 0.982 in training. The pattern predicted accurately with RMSE of 0.264 and MAE of 0.196. This paper shows that FL-ANFIS can predict steel bar bond strength in concrete quickly and accurately. The pattern reduces waste, design costs, and time.
... On the other hand, several previous studies that mainly focused on the member-level response have reported that the premature debonding failure mode was frequently noticed in RC members retrofitted with FRCM [18][19][20][21]. This failure mode may occur before attaining the FRCM composite system's ultimate strength, compromising the retrofit technique's effectiveness and reliability. ...
... The steel that used in substructures of bridges or in hydraulic structures in contact with water is subjected to corrosion when it is directly exposed to the natural environmental conditions. On the other hand, the concrete is subjected to cracks as a results of different loads (creep, fatigue, etc.) and these cracks lead to the corrosion of reinforcement bars [1][2][3][4]. As a result of the corrosion phenomena, the capacity of the structural element will decrease to the level that lead to the failure if the required engineering treatment are not taken. ...
... It is necessary to pay attention to the structural detailing that ensure the work of the structural elements as a one unit. The replacement method is a vary labor-intensive repair method [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The lack of available space to add additional supplemental element may be a factor limiting the use of this alternative. ...
... Therefore, it became necessary to search for alternatives that achieve engineering efficiency and lower costs. One of these alternatives is the use of FRP system [4]. FRP consist of fiber and resin, the function of the fiber is to carry the loads, while the functions of the resin are to bond the fibers together, transfer the load among the fibers and provide an external protection to the fibers. ...
The development of the use of advance composites is remarkable, especially in applications that require the materials used to be corrosion resistant. One of the most important of these applications is the structures built inside or under water, especially hydraulic structures. Constant exposure to wet makes materials such as concrete and steel threatened to the high level of corrosion and deterioration. The traditional methods for repairing proved insufficient over time, in addition to being expensive in some cases. Therefore, it became necessary to search for alternatives that achieve engineering efficiency and lower costs. One of these alternatives is the use of fiber reinforced polymer (FRP) system. Until recent years, it was not possible to use FRP system under water as a repair system for hydraulic structures without cofferdam. However, during this period, types of underwater cured resins were produced and underwater FRP system is the best choice for this type of structures. There are no many practical applications for the use of FRP in repairing of hydraulic structures, so it is possible to study its application in marine structure to show the possibility of use it in hydraulic structure. This research highlight the advantages and disadvantages of traditional method in repairing underwater structures. Also present project that considered the underwater FRP as a construction material used in the rehabilitation of deteriorated concrete pile. As a conclusion, using fibers with water activated resin can provide an economical solution for future repair and rehabilitation projects. Also the pre-preg system is efficient for repairing dry zones, while the wet layup system is very effective in repairing splash zones of damaged structural elements.
... Akbari and Nanni [32] applied a cyclic load to an RC beam reinforced with a glass FRCM to determine the ultimate strength, crack pattern, failure mode, bond performance, and fatigue threshold. Aljazaeri and Myers [33] examined the change in stiffness, crack and failure modes, and the energy absorption rate according to the curing conditions, and the sustained load and fatigue load conditions of RC beams when strengthened with FRCM. Aljazaeri and Myers [34] studied the change in stiffness through environmental exposure and fatigue frequency to a bridge exposed to various environments and verified that the resilience of FRCM was high even in the case of severe environmental exposure. ...
Textile-reinforced mortar (TRM) is used to strengthen reinforced concrete (RC) structures using a textile and inorganic matrix. TRM is a part of textile-based composites; the basic structural behaviors, application methods, and methodologies for the extension of actual structures in TRM were studied. However, structural behavior and performance verification which depict the long-term service situation and fatigue is limited. Therefore, this study, verified the flexural behavior of TRM-strengthened beams and their fatigue performances using carbon- and alkali-resistant (AR) glass textiles through 200,000 load cycles. TRM-strengthened beams were applied to an optimization strengthening method which consisted of whether the textile was straightened. According to the test results, the strengthening efficiency of TRM-strengthened beams when subjected to cyclic loading was lower than that of the monotonic loading, except for the straightened carbon textile specimen. The average efficiency of the AR-glass textile (straightened and non-straightened) and carbon (non-straightened) was 0.86 compared to the TRM-strengthened beam subjected to monotonic loading in terms of flexural strength. In the case of deflection, the average efficiency of the AR-glass textile type was similar to the monotonic loading test results, while that of the non-straightened carbon textile was improved. The Ca-S specimen that was used to straighten the carbon textile showed a reliable structural performance with a strength efficiency of 0.99 and a deflection efficiency of 0.97 compared to the monotonic load test. Therefore, TRM strengthening using a straightened carbon textile is expected to be sufficient for the fatigue design of TRM-strengthened beams.
... The steel that used in substructures of bridges or in hydraulic structures in contact with water is subjected to corrosion when it is directly exposed to the natural environmental conditions. On the other hand, the concrete is subjected to cracks as a results of different loads (creep, fatigue, etc.) and these cracks lead to the corrosion of reinforcement bars [1][2][3][4]. As a result of the corrosion phenomena, the capacity of the structural element will decrease to the level that lead to the failure if the required engineering treatment are not taken. ...
... It is necessary to pay attention to the structural detailing that ensure the work of the structural elements as a one unit. The replacement method is a vary labor-intensive repair method [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The lack of available space to add additional supplemental element may be a factor limiting the use of this alternative. ...
... Therefore, it became necessary to search for alternatives that achieve engineering efficiency and lower costs. One of these alternatives is the use of FRP system [4]. FRP consist of fiber and resin, the function of the fiber is to carry the loads, while the functions of the resin are to bond the fibers together, transfer the load among the fibers and provide an external protection to the fibers. ...
The development of the use of advance composites is remarkable, especially in applications that require the materials used to be corrosion resistant. One of the most important of these applications is the structures built inside or under water, especially hydraulic structures. Constant exposure to wet makes materials such as concrete and steel threatened to the high level of corrosion and deterioration. The traditional methods for repairing proved insufficient over time, in addition to being expensive in some cases. Therefore, it became necessary to search for alternatives that achieve engineering efficiency and lower costs. One of these alternatives is the use of fiber reinforced polymer (FRP) system. Until recent years, it was not possible to use FRP system under water as a repair system for hydraulic structures without cofferdam. However, during this period, types of underwater cured resins were produced and underwater FRP system is the best choice for this type of structures. There are no many practical applications for the use of FRP in repairing of hydraulic structures, so it is possible to study its application in marine structure to show the possibility of use it in hydraulic structure. This research highlight the advantages and disadvantages of traditional method in repairing underwater structures. Also present project that considered the underwater FRP as a construction material used in the rehabilitation of deteriorated concrete pile. As a conclusion, using fibers with water activated resin can provide an economical solution for future repair and rehabilitation projects. Also the pre-preg system is efficient for repairing dry zones, while the wet layup system is very effective in repairing splash zones of damaged structural elements.
... Mesticou et al. (2017) performed tensile tests in TRM coupons considering a low cycle fatigue scenario and concluded that whereas the TRM stiffness appears to be increasing with increasing number of cycles, the TRM strength remains constant. Aljazaeri et al. (2016) examined the effect of fatigue loading on the TRM to concrete bond indicating that the TRM strength decreases after approximately 2000000 cycles of applied loading, compared to the quasi-static case. There hence exists a research need for more tests to be conducted in order to quantify the mechanics of TRM bond under fatigue loading and identify the key parameters that regulate the bond between the TRM and the masonry substrate. ...
There is a growing interest in strengthening existing masonry buildings and structures due to their continuous structural deterioration, which is accelerated by the effect of adverse environmental actions, e.g., earthquakes, high-speed winds, heavy rainfalls and the continuous increase of traffic loads. Textile Reinforced Mortars (TRM) have been proven to provide several advantages over more traditional strengthening approaches; they are applicable in low temperatures, provide fire resistance, and are low cost. TRM, that belong to the more general family of Fabric Reinforced Cementitious Matrices (FRCM) - involve high strength fibre textile materials impregnated in inorganic cement or lime-based mortars. As in every externally bonded strengthening technique, one of the key parameters controlling the effectiveness of TRM is the bond between the strengthening material and the substrate. Over the past fifteen years, the mechanics of TRM to masonry bond have been investigated experimentally, analytically, and numerically for the case of quasi-static loading. However, experiments demonstrate a large variability vis-a-vis the anticipated bond strength. Conversely, the case of fatigue loading has not garnered much attention. Experiments conducted on FRP strengthened concrete specimens have demonstrated the detrimental effect of fatigue on the corresponding interfacial properties. With the objective of further investigating the effect of bond and contribute to the state-of-the-art in interface properties, this Thesis provides results from an experimental investigation on the TRM to masonry bond strength under monotonic and cyclic loading conditions. At the first stage, the textile reinforcement tensile properties were determined by carrying out tensile tests on bare textiles. Next, the bond behaviour between TRM and masonry substrate under quasi-static loading was extensively investigated. The investigated parameters were the bond length, the textile-fibre material and the epoxy resin coating. Finally, for the first time, a series of single-lap shear tests under fatigue loading has been conducted on textile fibre TRM bonded to masonry, considering various bond lengths and load ranges. The experimental results establish that TRM and masonry bond behaviour depends on textile materials used and the anchorage lengths. Furthermore, this work highlights the beneficial effect of the epoxy-resin coating compared to the uncoated counterpart specimens; it increases the fibre textiles’ tensile properties, improves the bonding conditions, and alters the failure mode of carbon and glass fibre-textile material. The results of bond behaviour under low cycle fatigue loading tests showed that the load range considerably affects the fatigue life of TRM strengthened components resulting in significantly lower strengths when compared to the quasi-static case.
... [2][3][4][5][6] Within the framework of the joint research project C 3 -Carbon Concrete Composite, 7 structural tests on flexural-strengthened RC members under monotonic and cyclic long-term loading were carried out with varying load levels, load frequencies and load cycles. Although many researchers have investigated this subject, 8-10 a precise analysis of the cross-sectional behavior including calculation parameters and assumptions to determine time-and load-dependent deflections under monotonic and cyclic long-term loading with direct comparison to experimental data is often missing. The topic of deflections is becoming increasingly important as the use of FRP reinforcement often leads to a smaller longitudinal stiffness EA of the reinforcement for the same load-bearing capacity compared to concrete members with reinforcing steel. ...
Strengthening of existing reinforced concrete (RC) structures by means of externally applied fiber-reinforced polymer (FRP) reinforcement was and still is an important research topic. CFRP reinforcement is particularly suitable for infrastructure projects where the actual loads have exceeded the predictions made in the past decades and high chloride input due to de-icing salts is also present. This article presents experimental and theoretical investigations on the structural behavior of RC members strengthened with an externally applied CFRP textile-reinforced concrete layer under monotonic and cyclic long-term loading. A precise analysis of the cross-sectional behavior and the calculation parameters to determine deflections and load-bearing capacities of the strengthened RC members is conducted. It is shown that the load-bearing capacity is not influenced by the preceding monotonic or cyclic long-term loading and despite the many influencing factors, a good agreement between the calculations and experimental data can be achieved.
... TRMs have a diverse variety of mechanical characteristics due to many types of textile and mortar matrices available. Alkali-resistant glass (ARG) [28][29][30], basalt [31][32][33][34], carbon [35][36][37][38][39], polyphenylene bezobisoxazole (PBO) [40,41] and other natural (e.g., flax [42,43], hemp [44] and sisal [45][46][47]) fibres are the most frequent non-metallic materials used in textiles and can be dried, coated or impregnated into the matrix. Figure 1a-f depict images of textiles made from various fibre materials and geometries. ...
Fibre-reinforced cement mortar (FRCM) has been widely utilised for the repair and restoration of building structures. The bond strength between FRCM and concrete typically takes precedence over the mechanical parameters. However, the bond behaviour of the FRCM–concrete interface is complex. Due to several failure modes, the prediction of bond strength is difficult to forecast. In this paper, effective machine learning models were employed in order to accurately predict the FRCM–concrete bond strength. This article employed a database of 382 test results available in the literature on single-lap and double-lap shear experiments on FRCM–concrete interfacial bonding. The compressive strength of concrete, width of concrete block, FRCM elastic modulus, thickness of textile
layer, textile width, textile bond length, and bond strength of FRCM–concrete interface have been taken into consideration with popular machine learning models. The paper estimates the predictive accuracy of different machine learning models for estimating the FRCM–concrete bond strength and found that the GPR model has the highest accuracy with an R-value of 0.9336 for interfacial bond strength prediction. This study can be utilising in the estimation of bond strength to minimise the experimentation cost in minimum time.
