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In this study, ten shear walls were experimentally tested to examine behaviour of ferrocement hollow shear walls subjected to axial and lateral loads. Ferrocement mortar (FM) was used to build eight walls, while normal concrete (NC) was used to build two controls. Walls were lateral reinforced using conventional stirrups, two layers of welded wire mesh (WWM), and expanded steel mesh (ESM). Two specimens lacked lateral reinforcement except for one transverse web in the center of the inner hole. Two symmetric groups of five walls each were created by dividing the walls. While the other group was loaded laterally, one group was loaded axially. In each group, the load–displacement relationship, maximum load and associated displacement, stiffness, ductility, and failure mechanism of FM and NC walls were compared. The results showed that FM walls provided with ESM and WWM had ultimate axial loads that were, respectively, 36% and 19% higher than NC control walls. Ultimate lateral loads and related ultimate drifts of FM walls reinforced with two layers of WWM and ESM were, respectively, 68% and 39%, 96% and 43.5%, larger than control NC wall. For lateral loads greater than those applied to the NC control wall, stiffness increase ratios for FM walls ranged from 2.5% to 89.5%, and for axial loads, they ranged from 20% to 150.5%. The ductility of FM walls increased when compared to NC walls by 58.5% and 158.8% for axial and lateral loading, respectively, when two layers of WWM were utilized to lateral reinforce FM walls. When two layers of ESM were applied to laterally reinforce FM walls in comparison to an NC wall, this increased the walls' ductility under axial and lateral loads by 110.5% and 214.7%, respectively. [ABSTRACT FROM AUTHOR]

In our investigation, we subjected eleven reinforced concrete beams to a four-point bending system to explore the impact of varying fibre and ferrocement contents on their structural behaviour. These beams, measuring 1.7 m in length, featured a rectangular cross-section with dimensions of 150 mm by 300 mm. Our study focused on three key variables: steel fibre content (at levels of 0.5%, 1%, and 1.5%), glass fibre content (also at 0.5%, 1%, and 1.5%), and ferrocement content (evaluated with one or two layers of welded or expanded wire mesh). Our findings revealed that incorporating fibres with minimal shear reinforcement significantly enhanced the beams' performance. Specifically: The specimen reinforced with 1.5% steel fibres exhibited the highest ultimate failure load, surpassing the control beam by an impressive 41.87%. The 0.5% glass fibre specimen experienced the least deflection at the ultimate load compared to the control beam. The 1.5% glass fibre specimen demonstrated superior energy absorption compared to the control specimen. Notably, using two layers of welded wire mesh proved most effective in enhancing the ultimate failure load when compared to both the control specimen and other ferrocement-strengthened beams. [ABSTRACT FROM AUTHOR]

The incorporation of high-strength steel wire mesh and polyurethane cement (HSSWM–PUC) has been identified as an effective approach for enhancing existing reinforced structures. This study comprehensively examined the flexural performance of reinforced concrete (RC) T-beams fortified with HSSWM–PUC composite material, proposing an accurate formula to calculate flexural capacity. This formula took into account various factors such as the strengthening ratio of HSSWM, laminate thickness, the type of bonding anchorage material, the presence of end anchorage, and the degree of initial damage. Flexural tests were conducted on one contrast beam and six reinforced beams within the scope of this research. Subsequent analyses revealed that the application of HSSWM–PUC significantly elevates the flexural capacity of both damaged and undamaged beams. This indicates that the load-bearing capacity correspondingly improves as the PUC thickness increases. With an increase in PUC thickness from 20 to 30 mm, the reinforced beam showed a 34% improvement in ultimate load and a 31.7% increase in yield load. Compared under similar parameters, beams strengthened with HSSWM–PUC showed a 43% higher cracking load than HSSWM–PM, especially with eight longitudinal high-strength steel wire ropes and a 20-mm-thick PUC layer. Additionally, using a U-shaped anchorage at the end provided a 20% advantage. A further merit of the HSSWM–PUC approach lies in its capability to both restrain the formation of concrete cracks and retard the progression of such defects, thereby fortifying the structural integrity. The observed failure mode was predominantly flexural, distinctly avoiding the common peeling failure witnessed between strengthening laminates and concrete. This suggests that HSSWM–PUC stands as a credible solution for amplifying the durability and lifespan of RC structures. [ABSTRACT FROM AUTHOR]

Starting with the premise that the choice of the optimal method for strengthening reinforced concrete (RC) structures is a complex task and that ferrocement strengthening is comparable to other advanced strengthening technologies due to its cost-effectiveness, ease of construction, and durability, this paper presents a comparative study of the flexural bearing capacity of RC beams strengthened with ferrocement strips applied by gluing. An overview of the life cycle assessment (LCA) based on embodied energy or CO2 is presented in the introduction, based on the existing literature review. The research includes tests of 15 RC beams of identical cross-sections (150/250 mm) and a span of 3000 mm. Strengthening was conducted by applying four types of ferrocement strips (different widths and wire mesh layers). Two factors were examined: the verification of the comprehensive FEM numerical model against the experimental results and the applicability of existing simplified calculation methods for sufficiently accurate results which could be used in regular practice. The results show that the failure forces obtained from numerical models and experimental models differ by no more than 3.94%. The increase in the bearing capacity of the strengthened models is up to 21.4%. The transformed area method for the cracked section showed good results when compared to the FEM and experimental models. The analytically calculated failure force is contingent upon the partial factor for variable action, which was explored within the 1.5–1.7 range. [ABSTRACT FROM AUTHOR]

Numerical and regression modelling of 21 undamaged, fire-damaged and repaired fire-damaged circular reinforced concrete (RC) columns was undertaken. The columns were exposed to temperatures of 300°C, 500°C and 900°C and tested for axial residual capacity. It was found that the concrete lost strength after exposure to a temperature of 300°C or above. Fire-damaged columns were then repaired using various composite confinement techniques. Strength was regained when carbon-fibre-reinforced polymer (CFRP) confinement was applied to the fire-damaged columns but it also increased the deformation and thus reduced the stiffness, which is undesirable. As an alternative, steel wire mesh, filled with cement–sand mortar and wrapped with CFRP was employed. A numerical model to predict the residual capacity of these columns was developed. The development of numerical techniques, including material properties, geometry, elements, loading, boundary conditions and contact algorithms for undamaged, fire-damaged and repaired fire-damaged columns is reviewed and summarised. Analytical equations were developed using linear, multiple and quadratic regression modelling. The results obtained using the proposed model and regression equations showed that these models offer a better alternative to experimental testing for the prediction of the post-fire performance of damaged and repaired RC columns. [ABSTRACT FROM AUTHOR]

The electrical resistivity tomography (ERT) method is often challenged by the presence of reinforced concrete (RC) in urban and industrial environments, because the embedded metallic wire mesh can severely distort the distribution of subsurface currents. We investigate one typical scenario in real applications, in which an RC floor overlays the natural topsoil or rock. Our synthetic forward simulations show that the embedded wire mesh behaves like a local good conductor in data of small source‐receiver separations and acts like an equal‐potential object that keeps the potential from decaying at large source‐receiver separations. Routine ERT inversions that ignore the RC cannot work properly because the thin and highly conductive wire mesh may be manifested as large uninterpretable low‐resistivity anomalies in the imaging results. Two remedies are adopted to improve the ERT resolution in such cases. First, we find a top layer with high conductivity in our model to adequately represent the wire mesh; then, we initiate the inversion with the top‐layer model as the starting and reference model. This warm‐start approach overcomes the difficulty of recovering the large conductivity contrast between metallic objects and regular earth materials. Second, underground electrodes are added to the survey array, so more information from depth can be obtained to fight against the dominance of current channelling in the wire mesh. Finally, our strategies are used to invert a real ERT dataset from an indoor manufacturing plant, where RC covers the entire floor of the building and electrodes are in contact with the soil through open holes in the floor. Our simulation and field data inversion verify our findings and demonstrate the effectiveness of our solutions in improving the resolution of ERT when the survey is carried out over RC floor in urban and industrial environments. [ABSTRACT FROM AUTHOR]

A novel strengthening scheme of high-strength stainless steel wire rope (HSSSWR) meshes reinforced engineering cementitious composite (ECC) jacket was used to strengthen the reinforced concrete (RC) short columns in this paper. The seismic performance of short columns after being strengthened was investigated, considering the changes in the strengthening scheme, and the spacing of lateral HSSSWRs. The failure mode, hysteresis behavior, envelope curve, ductility, energy dissipation, stiffness degradation, and strength degradation were introduced specifically based on the analysis of six full-scale short columns. The test results show a significant enhancement in the seismic performance of the strengthened short columns, especially in ductility and energy dissipation, which were increased by 49.4–98.4 %, and 149.3–713.2 %, respectively. The placement of HSSSWRs in ECC jacket proved to be effective in enhancing the strengthening effect of the jacket. A prediction model for the shear capacity of the strengthened columns was proposed using the Modified Compression Field Theory (MCFT), and the predicted results were in good agreement with the test results presented in this paper and in relative study. • The RC short columns were strengthened by different ECC jacket and corresponding cyclic loading tests were conducted. • The influence of different ECC jackets on seismic improvement of short columns was revealed. • The prediction model based on the MCFT was proposed to predict the shear capacity of strengthened columns. [ABSTRACT FROM AUTHOR]

• A total of fifteen one-way slabs were tested in four-point bending scheme. • Nine slabs were strengthened with ferrocement jackets, three were strengthened with CFRP, and two were strengthened with GFRP jackets. • The study focused on preventing debonding of the strengthening layers, employing either mechanical or chemical anchors. • The use of chemical anchors demonstrated a superior ability to delay debonding and enhance ductility compared to mechanical anchors. • The orientation of the wire mesh also played a crucial role, with parallel orientation to the longitudinal axis of slabs yielding better performance. Existing research lacks focus on the structural behavior of reinforced concrete (RC) one-way slabs reinforced with ferrocement, and there's a notable absence of comparative studies between fiber-reinforced polymers (FRPs) and ferrocement strengthening methods for these slabs. Given the cost-effectiveness and widespread use of ferrocement in structural reinforcement, this study aimed to address these gaps through an experimental program. Three sizes of wire mesh, categorized as Type-I (small), Type-II (medium), and Type-III (large), were employed in this study. Chemical or mechanical anchors were used to attach ferrocement jackets. Moreover, 6, 12, or 18 anchors were used to assess the effect of anchor configuration. The goal was to enhance the structural performance of slabs and compare them with slabs reinforced using FRP jackets. The study focused on preventing debonding of the strengthening layers, employing either mechanical or chemical anchors. All slabs exhibited ductile failure with flexural cracks. The peak load and ultimate deflection were enhanced by up to 49.00% and 109.07%, respectively, by the application of ferrocement jackets, whereas the dissipated energy was increased by up to 174.00 %. Notably, the use of chemical anchors demonstrated a superior ability to delay debonding and enhance ductility compared to mechanical anchors. Slabs reinforced with glass FRP (GFRP) showed delayed debonding relative to carbon FRP (CFRP) reinforced slabs, indicating the superior performance of chemical anchors with GFRP layers. Moreover, the type and size of wire mesh significantly influenced performance, with small and medium-sized mesh configurations enhancing ductility, while large-sized mesh exhibited relatively earlier debonding. The orientation of the wire mesh also played a crucial role, with parallel orientation to the longitudinal axis of slabs yielding better performance. [ABSTRACT FROM AUTHOR]