To see the other types of publications on this topic, follow the link: Fiber Reinforced Cementitious Matrix (FRCM).
Journal articles on the topic 'Fiber Reinforced Cementitious Matrix (FRCM)'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Fiber Reinforced Cementitious Matrix (FRCM).'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Incerti, Andrea, Mattia Santandrea, Christian Carloni, and Claudio Mazzotti. "Destructive In Situ Tests on Masonry Arches Strengthened with FRCM Composite Materials." Key Engineering Materials 747 (July 2017): 567–73. http://dx.doi.org/10.4028/www.scientific.net/kem.747.567.
Full textAbstract:
In the last few decades, fiber reinforced polymer (FRP) composites have been widely employed in several strengthening and rehabilitation applications of existing masonry buildings. Fiber reinforced cementitious matrix (FRCM) composites are a newly-developed strengthening technique comprised of high strength fibers embedded in a cementitious matrix. FRCMs usually offer several advantages such as the high resistance to fire and high temperatures or vapor permeability with masonry substrate, therefore they appear to be a promising alternative to traditional FRP strengthening systems. In this experimental work, the results of destructive in situ tests performed on existing masonry arches strengthened with FRCM composites are reported. FRCM strips consist of a balanced bi-axial mesh made of basalt fibers embedded in a cementitious grout. Three different configurations of the strengthening system have been considered. Load responses and failure modes are presented.
2
D'Antino, Tommaso, Carlo Pellegrino, Christian Carloni, Lesley H. Sneed, and Giorgio Giacomin. "Experimental Analysis of the Bond Behavior of Glass, Carbon, and Steel FRCM Composites." Key Engineering Materials 624 (September 2014): 371–78. http://dx.doi.org/10.4028/www.scientific.net/kem.624.371.
Full textAbstract:
In recent decades, the construction industry has witnessed a rapid growth of interest in strengthening and retrofitting of existing reinforced concrete (RC) and masonry structures. Fiber reinforced polymer (FRP) composites have gained great popularity, and several studies are now available in the literature on their use in strengthening and retrofit applications. Promising newly-developed composite materials are represented by the so-called fiber reinforced cementitious matrix (FRCM) composites. FRCM composites are comprised of high strength fibers embedded within a cementitious matrix that is responsible for the stress transfer between the existing structure and the strengthening material. FRCM composites are still in their infancy, and very limited results are available in the literature on RC and masonry strengthening applications. This study presents an experimental campaign conducted on different FRCM composites comprised of glass, carbon, or steel fibers embedded within two different cementitious matrices and applied to concrete prisms. The single-lap direct-shear test was used to study the stress-transfer mechanism between the FRCM composite and the concrete substrate. Two different composite bonded lengths were investigated. Debonding occurred at the matrix-fiber interface for some of the composites tested and at the concrete-matrix interface for others. This work contributes to the study of the bond behavior of FRCM composites, which represents a key issue for the effectiveness of FRCM composite strengthening.
3
Bilotta, Antonio, and Gian Piero Lignola. "Effects of Defects on Bond Behavior of Fiber Reinforced Cementitious Matrix Materials." Materials 13, no. 1 (January 1, 2020): 164. http://dx.doi.org/10.3390/ma13010164.
Full textAbstract:
High-strength fibers embedded in inorganic matrix i.e., Fiber Reinforced Cementitious Mortar materials (FRCM) are commonly used as strengthening technique for existing masonry structures, due to the low sensitivity to debonding phenomena between substrate and matrix. Nevertheless, the use of lime or cement-based matrix instead of epoxy adhesive implies that attention has to be paid to the bond behavior between the fibers and the matrix, since sliding phenomena and cohesive failures in the mortar matrix can occur. The paper aims to investigate the effect of the mechanical properties of fiber and matrix on the FRCM efficiency, and potential geometrical defects, typical of real applications. The aim is to analyze the mechanical behavior of the FRCM system by simulating hypothetical bond tests, as they are usually performed in laboratories. The bond test has a significant role, as it is used for the qualification of the material, providing sometimes very scattered results. Hence, it is particularly important and greatly discussed in the scientific community and among manufactures and practitioners. The purpose is to understand where this variability could derive from and possibly how to contain it, to improve the characterization of FRCM systems. A mechanical model has been proposed to simulate the usual bond test to focus and stress the way in which each fiber slips out of the matrix as the load increases; and this has been recognized as the main reason for scattered results in bond tests. The model was then applied to the typical cases of PBO-FRCM and Glass-FRCM, hence considering different ratios for the fiber and matrix properties.
4
D'Antino, Tommaso, Francesca Giulia Carozzi, Pierluigi Colombi, and Carlo Poggi. "A New Pull-Out Test to Study the Bond Behavior of Fiber Reinforced Cementitious Composites." Key Engineering Materials 747 (July 2017): 258–65. http://dx.doi.org/10.4028/www.scientific.net/kem.747.258.
Full textAbstract:
Fiber reinforced cementitious matrix (FRCM) composites are gaining increasing popularity in the civil engineering community. FRCM composites are comprised of high-strength fiber textiles embedded within inorganic matrices that are responsible for the stress-transfer mechanism between the composite and the substrate. Failure of FRCM composites including one layer of textile is generally reported to be debonding of the fibers from the embedding matrix. Therefore, the bond behavior of the matrix-fiber interface is of critical importance for these types of composites.This paper presents the results of an experimental campaign carried out to investigate the bond behavior of an FRCM composite comprising PBO fibers. Specimens were tested using a newly-developed pull-out test set-up. The results obtained are compared with those obtained by different authors on single-lap direct-shear tests with the same FRCM composite.
5
Al-Lami, Karrar, Tommaso D’Antino, and Pierluigi Colombi. "Durability of Fabric-Reinforced Cementitious Matrix (FRCM) Composites: A Review." Applied Sciences 10, no. 5 (March 2, 2020): 1714. http://dx.doi.org/10.3390/app10051714.
Full textAbstract:
Strengthening and rehabilitation of masonry and concrete structures by means of externally bonded fabric-reinforced cementitious matrix (FRCM) (also referred to as textile reinforced mortar (TRM)) composites was proposed as an alternative to the use of fiber-reinforced polymer (FRP) composites due to their good mechanical properties and compatibility with the substrate. However, quite limited studies are available in the literature regarding the long-term behavior of FRCM composites with respect to different environmental conditions. This paper presents a thorough review of the available researches on the long-term behavior of FRCM composites. Namely, (i) test set-ups employed to study the FRCM durability, (ii) conditioning environments adopted, and (iii) long-term performance of FRCM and its component materials (mortar and fiber textile) subjected to direct tensile and bond tests, are presented and discussed. Based on the available results, some open issues that need to be covered in future studies are pointed out.
6
Gonzalez-Libreros, Jaime, Tommaso D'Antino, and Carlo Pellegrino. "Experimental Behavior of Glass-FRCM Composites Applied onto Masonry and Concrete Substrates." Key Engineering Materials 747 (July 2017): 390–97. http://dx.doi.org/10.4028/www.scientific.net/kem.747.390.
Full textAbstract:
The use of Fiber Reinforced Polymer (FRP) composites has become a popular solution for retrofitting and strengthening of existing concrete and masonry structures. However, some drawbacks of this technique, mainly associated with the use of organic resins, have been reported. To overcome such drawbacks, the development of composite materials in which the organic resins are replaced with inorganic matrices has recently caught the attention of the civil engineering industry. Among these newly developed systems, Fiber Reinforced Cementitious Matrix (FRCM) composites, which are comprised of high strength fibers embedded within an inorganic matrix, have shown promising results. However, research on this topic is still limited and important aspects, such as the bond behavior between the composite and the substrate, are not fully understood and require further study. This paper presents the results of an experimental campaign aimed at investigating the influence of the type of matrix and substrate on the bond behavior of FRCM composites. Glass-FRCM composite strips were applied onto concrete and masonry substrates and then tested by means of a classical push-pull single-lap direct-shear test set-up. A cementitious and a lime-based matrix were employed to apply the same type of fiber on concrete and masonry substrates, respectively. FRCM-concrete and FRCM-masonry joints reported the same failure mode. However, higher values of the peak load were obtained for the lime-based glass-FRCM composite applied onto masonry substrates than with the cementitious glass-FRCM composite applied onto concrete substrates.
7
Blikharskyy, Z., K. Brózda, and J. Selejdak. "Effectivenes of Strengthening Loaded RC Beams with FRCM System." Archives of Civil Engineering 64, no. 3 (September 1, 2018): 3–13. http://dx.doi.org/10.2478/ace-2018-0025.
Full textAbstract:
AbstractThe composite materials as FRP (Fiber Reinforced Polymers), which are characterized by benefits resulting from the combination of high strength reinforcement (as carbon, glass, steel or aramid fibers) with synthetic matrix are increasingly used to reinforce existing structures. Reinforcing System as FRCM (Fibre Reinforced Cementitious Matrix), which includes, among others, Ruredil X Mesh Gold System, is much less commonly used. However, the uniform and practical methods for calculating composite reinforced structures are not determined. Especially when considering the real conditions of structure exploitation, which requires further research in this field. In the paper the initial loading level influence on the efficiency of reinforced concrete beams strengthen using system Ruredil X Mesh Gold was investigated.
8
Santandrea, Mattia, Gilda Daissè, Claudio Mazzotti, and Christian Carloni. "An Investigation of the Debonding Mechanism between FRCM Composites and a Masonry Substrate." Key Engineering Materials 747 (July 2017): 382–89. http://dx.doi.org/10.4028/www.scientific.net/kem.747.382.
Full textAbstract:
Fiber reinforced cementitious matrix (FRCM) composites have recently become a hot topic in Europe as an alternative to traditional fiber reinforced polymer (FRP) composites for several strengthening applications of existing masonry buildings. The terrific success of this new retrofitting system is mainly due to some advantages that it offers when compared to FRP, such as the possibility of application of the composite to wet surfaces and the vapor permeability featured by the inorganic matrix. In this work, the stress transfer between FRCM composites and a masonry substrate is investigated. FRCM strips comprised of ultra-high-strength steel fibers embedded in a cementitious grout are externally bonded to masonry blocks. Single-lap direct shear tests are performed. Parameters studied are bonded length and density of the steel fibers. Load responses are presented and failure modes are discussed. Change in the bond behavior and load carrying capacity with increasing bonded length is analyzed to determine the effective bond length.
9
Santandrea, Mattia, Giovanni Quartarone, Christian Carloni, and Xiang Lin Gu. "Confinement of Masonry Columns with Steel and Basalt FRCM Composites." Key Engineering Materials 747 (July 2017): 342–49. http://dx.doi.org/10.4028/www.scientific.net/kem.747.342.
Full textAbstract:
The rehabilitation of existing masonry elements by means of jacketing of columns using composite materials is becoming a remarkable technique in several applications that aim to increase the strength of existing masonry buildings. Fiber reinforced cementitious matrix (FRCM) composites are a newly developed strengthening system that consist of high-strength fibers embedded in a cementitious grout and externally bonded to the substrate. High resistance to fire and high temperatures, ease of handling during application, and vapor permeability with the substrate are some of the characteristics that make FRCMs a promising alternative to traditional organic composites such as fiber reinforced polymer (FRP) composites. This work presents the results of an experimental study carried out to understand the behavior of masonry columns with a square cross-section confined by steel and basalt fiber sheets embedded in a mortar matrix subjected to monotonic concentric compressive load. The effectiveness of the confinement is studied in terms of load-bearing capacity with respect to unconfined columns. The effect of corner radius for columns confined with basalt fibers is investigated.
10
Carloni, Christian, Claudio Mazzotti, Marco Savoia, and Kolluru V. Subramaniam. "Confinement of Masonry Columns with PBO FRCM Composites." Key Engineering Materials 624 (September 2014): 644–51. http://dx.doi.org/10.4028/www.scientific.net/kem.624.644.
Full textAbstract:
The overarching goal of this work is to provide a fundamental understanding of the behavior of solid brick masonry columns confined with fiber reinforced cementitious matrix (FRCM) composites. FRCM is a newly-developed type of composite material comprised of a cementitious inorganic matrix (binder) and embedded fibers that are usually bundled to improve the bond between the matrix and the fibers. Compression tests were carried out to investigate the influence of the FRCM confinement and the brick patterns on the load-carrying capacity of the confined columns. Compression tests were conducted on brick masonry columns with different brick configurations. Digital image correlation measurements on the surface of the composite and on the surface of the brick for the control specimens were attempted in order to understand the role of the mortar joints and the arch effect across the section of the columns due to the confinement. The experimental results indicate that FRCM composites can effectively increase the load-carrying capacity of brick masonry columns and the failure mode could be different from the one observed for masonry columns confined with fiber-reinforced polymer (FRP) composites.
11
Pekmezci, Bekir Yılmaz, and Ali Çopuroğlu. "Mechanical Properties of Carbon-Fabric-Reinforced High-Strength Matrices." Materials 13, no. 16 (August 9, 2020): 3508. http://dx.doi.org/10.3390/ma13163508.
Full textAbstract:
Fabric-reinforced cementitious matrices (FRCM) are promising technologies that respond to today’s architectural approaches. However, due to their high strength and ductility, they are starting to be implemented in buildings as strengthening systems. In this experimental study, the amount of fiber along the load direction in high-strength cementitious matrices and the effects of the fiber orientation on FRCM mechanical properties were studied. A total of four different composites were produced with two fabrics and two matrices. Tensile and flexural tests were carried out on composites. Within the scope of microstructure studies, scanning electron microscope micrographs were obtained and analyzed, along with microtopography sections. The main result obtained from the study indicates that as the fiber area in the direction of the load increases, the load order carried in this direction increases. However, this increase does not have to be proportional to the fiber area used in the direction of the load. The fiber coating and coating matrix interface play important roles in a composite’s performance. The carbon fibers can be used more efficiently by using them along the load direction and the loads in the matrix can be transferred to the carbon fibers by creating a larger fiber–matrix interface area.
12
Ombres, Luciano, Antonio Iorfida, and Salvatore Verre. "FRCM/SRG - Masonry Joints: Experimental Investigation and Numerical Modelling." Key Engineering Materials 817 (August 2019): 3–8. http://dx.doi.org/10.4028/www.scientific.net/kem.817.3.
Full textAbstract:
The results of single-lap shear tests, performed on specimens with Fiber Reinforced Cementitious Matrix (FRCM) or Steel Reinforced Grout (SRG) composite strips bonded to masonry unit, are presented in this paper. This study indicates a different type of failure modes occur in PBO FRCM and SRG – masonry joints, respectively. The PBO-FRCM exhibited the typically telescopic failure mode while the SRG shows a slippage of the fibers and fracture of the external matrix layer at the fiber-matrix interface for both the composite systems investigated. Moreover, a 3D numerical model by the commercial code ABAQUS was realized, it is calibrated on the results present in this study. The macro model approach was used with two different bond-slip relationships present in literature. The validity of the numerical model is verified by the comparison with the experimental results in terms of the applied load-global slip and the crack patterns.
13
Murgo, Francesco Saverio, Francesca Ferretti, and Claudio Mazzotti. "A discrete-cracking numerical model for the in-plane behavior of FRCM strengthened masonry panels." Bulletin of Earthquake Engineering 19, no. 11 (May 28, 2021): 4471–502. http://dx.doi.org/10.1007/s10518-021-01129-6.
Full textAbstract:
AbstractIn this paper, the structural behavior of masonry panels strengthened with a system made up of composite fiber grids embedded in a cementitious matrix (FRCM) is presented. The non-linear behavior of the unreinforced and reinforced panels is numerically simulated by means of a simplified micro-modelling approach. This approach concentrates all the non-linearities and failures in the joints and in potential crack surfaces within the bricks, placed vertically in the middle of each brick. The FRCM strengthening system is discretized by a continuous bi-directional fiber grid constituted by trusses embedded into a cementitious matrix. A calibrated bond-slip relationship is applied between the fibers and the mortar matrix assuming an idealized bilinear law. The typical experimental load–displacement curve for a FRCM strengthened panel shows three principal phases that correspond to different failure mechanisms: masonry cracking, mortar matrix cracking and ultimate failure of the panel. The non-linear numerical analyses show a good agreement with experimental results and the modeling approach is found to be adequate to reproduce the described experimental behavior. The results of a parametric study on both the material and the geometrical properties of the FRCM system are also presented.
14
Lee, Sugyu, Kinam Hong, Yeongmo Yeon, and Kyusan Jung. "Flexural Behavior of RC Slabs Strengthened in Flexure with Basalt Fabric-Reinforced Cementitious Matrix." Advances in Materials Science and Engineering 2018 (2018): 1–12. http://dx.doi.org/10.1155/2018/2982784.
Full textAbstract:
This paper presents both experimental and analytical research results for predicting the flexural capacity of reinforced concrete (RC) slabs strengthened in flexure with basalt fabric-reinforced cementitious matrix (FRCM). A total of 13 specimens were fabricated to evaluate the flexural behavior of RC slabs strengthened with basalt FRCM composite and were tested under four-point loading. The fiber type, tensile reinforcement ratio, and the number of fabric layers were chosen as experimental variables. The maximum load of FRCM-strengthened specimens increased from 11.2% to 98.2% relative to the reference specimens. The energy ratio and ductility of the FRCM-strengthened specimens decreased with the higher amount of fabric and tensile reinforcement. The effective stress level of FRCM fabric can be accurately predicted by a bond strength of ACI 549 and Jung’s model.
15
Jung, Kyusan, Kinam Hong, Sanghoon Han, Jaekyu Park, and Jaehyun Kim. "Shear Strengthening Performance of Hybrid FRP-FRCM." Advances in Materials Science and Engineering 2015 (2015): 1–11. http://dx.doi.org/10.1155/2015/564876.
Full textAbstract:
The effectiveness of a hybrid fiber reinforced polymer- (FRP-) fabric reinforced cementitious matrix (FRCM) for shear strengthening was investigated though an experimental study. FRP materials of FRCM are usually fabricated in the form of a fabric to enhance the bond strength between the FRP material and the cementitious matrix. The hybrid FRP fabric used in this study consisted of carbon FRP (CFRP) and glass FRP (GFRP) in warp and weft directions, respectively. A total of 11 beams were fabricated and 8 beams among them were strengthened in shear with externally bonded hybrid FRP-FRCM. The number of plies, the bond types, and the spacing of the hybrid FRP fabric were considered as experimental variables. Additionally, a shear capacity model for a FRCM shear strengthened beam was proposed. The values predicted by the proposed model were compared with those by the ACI 549 code and test results. It was confirmed from the comparison that the proposed model predicted the shear strengthening performance of the hybrid FRP-FRCM more reliably than the ACI 549 code did.
16
Bencardino, Francesco, Mattia Nisticò, Luciano Ombres, and Salvatore Verre. "Mechanical Behavior and Failure Modes of Two Different Steel-FRCM Systems on Masonry Substrate: Experimental Investigation." Key Engineering Materials 817 (August 2019): 466–71. http://dx.doi.org/10.4028/www.scientific.net/kem.817.466.
Full textAbstract:
The results of single-lap shear tests, carried out on specimens with Steel Fabric Reinforced Cementitious Matrix (S-FRCM) composite strips bonded to masonry units, are presented in this paper. The S-FRCM composite system represents a newly developed promising technique for strengthening the masonry structures. The S-FRCM composite was comprised of steel fiber strip embedded within two layers of inorganic matrix. Two kinds of steel fibers can be used: ultra-high tensile strength steel galvanized micro-cords and/or stainless steel strands. The main differences between the two fibers are: E modulus with a ratio of 2.58 and tensile strength with a ratio of 2.04. This experimental investigation was carried out in order to obtain the information on the fundamental behavior of the bond between masonry and the two types of S-FRCM composites, which is the critical phenomenon in structural strengthening applications due to a slip of the fibers and fracture of the external matrix layer at the fiber-matrix interface. The results were analyzed and showed in terms of failure modes, failure loads, load-global slip curves, and other parameters.
17
Grzymski, Filip, Dorota Marcinczak, Tomasz Trapko, and Michał Musiał. "FRCM composites mesh anchorage – a way to increase strengthening effectiveness." MATEC Web of Conferences 251 (2018): 02044. http://dx.doi.org/10.1051/matecconf/201825102044.
Full textAbstract:
FRCM (Fabric Reinforced Cementitious Matrix) composites are the next stage of development of composite structural reinforcement after FRP (Fibre Reinforced Polymers) composites. The main element that distinguishes the newer FRCM system is the matrix of the composite – mineral matrix instead of epoxy resin. Changes in the structure of the composite, resulting from the change of the matrix, have a big impact on its work mechanisms. This paper discusses FRCM composites and shows its effectiveness in reinforced concrete elements strengthening. The basic information on FRCM mesh fibres material differences and composite failure modes are given. Current trends and directions of composite structural strengthening and the latest research in the area of increasing FRCM composite strengthening effectiveness, that are being conducted by the authors, are presented.
18
Ombres, Luciano. "Confinement Effectiveness in Eccentrically Loaded Masonry Columns Strengthened by Fiber Reinforced Cementitious Matrix (FRCM) Jackets." Key Engineering Materials 624 (September 2014): 551–58. http://dx.doi.org/10.4028/www.scientific.net/kem.624.551.
Full textAbstract:
Abstract.The paper is devoted to the analysis of the effectiveness of the Carbon Fiber Reinforced Cementitious Matrix (C-FRCM) as confinement system of the masonry and the characterization of the structural response of masonry column confined by C-FRCM jackets, accounting for all geometrical and mechanical involved parameters. At this aim, tests on confined masonry column under eccentric axial load were carried out. Five masonry column having an overall length of650 mm, with rectangular cross-section,250 x250 mm, were eccentrically loaded until collapse; two specimens were un-confined and used as control specimens, two specimens were confined with one layer of C-FRCM and one specimen was confined with two layers of C-FRCM. The eccentricity values considered weree/H=0ande/H=0.20, being H the height of the section. Failure modes and load-strain diagrams were considered to analyze test results and to evaluate the effectiveness of the confinement both in terms of strength and ductility.
19
Calabrese, Angelo Savio, Tommaso D’Antino, Pierluigi Colombi, Christian Carloni, and Carlo Poggi. "Fatigue Behavior of PBO FRCM Composite Applied to Concrete Substrate." Materials 13, no. 10 (May 21, 2020): 2368. http://dx.doi.org/10.3390/ma13102368.
Full textAbstract:
Several reinforced-concrete (RC) structural elements are subjected to cyclic load, such those employed in highway and railroad bridges and viaducts. The durability of these elements may be reduced as a consequence of fatigue, which mainly affects the steel reinforcement. The use of externally bonded (EB) fiber-reinforced cementitious matrix (FRCM) composites allows the moment capacity to be shared by the internal reinforcement and the EB composite, thus increasing the fatigue life of the strengthened RC member. The effectiveness of EB FRCM composites is related to the composite bond properties. However, limited research is currently available on the effect of fatigue on the bond behavior of FRCM-substrate joints. This study provides first the state of the art on the fatigue behavior of different FRCM composites bonded to a concrete substrate. Then, the fatigue bond behavior of a polyparaphenylene benzo-bisoxazole (PBO) FRCM is experimentally investigated using a modified beam test set-up. The use of this set-up provided information on the effect of fiber-matrix interface shear and normal stresses on the specimen fatigue bond behavior. The results showed that fatigue loading may induce premature debonding at the matrix-fiber interface and that stresses normal to the interface reduce the specimen fatigue life.
20
Verre, Salvatore, Alessio Cascardi, Maria Antonietta Aiello, and Luciano Ombres. "Numerical Modelling of FRCMs Confined Masonry Column." Key Engineering Materials 817 (August 2019): 9–14. http://dx.doi.org/10.4028/www.scientific.net/kem.817.9.
Full textAbstract:
The Fabric Reinforced Cementitious Matrices (FRCMs) are promising strengthening solution for existing masonry since the inorganic matrix is considerably compatible with historical substrates. Nevertheless, the matrix is responsible for the stress-transfer in composites so, in case of poor-quality mortar, the effectiveness of the strengthening can be limited or even compromised. For this reason, a few studies have been targeted to this aspect in the recent past, while numerical investigations are still limited. The present paper refers to a Finite Element (FE) analysis of masonry columns confined with FRCM composites developed by Abaqus-code and based on the macro-model approach. At this scope, available experimental results were used for the calibration regarding different types of the matrix (lime and cement based) for FRCM-confinement. The model was performed by using the Plastic (P) and the Concrete Damage Plasticity (CDP) material constitutive laws. The FRCM-strengthened system was preliminary modeled as a homogenous elastic material until failure. Typical failures of FRCM-systems are the detachment of the matrix from the substrate, slippage of the fibers within the embedding matrix, detachment of the composite strip at the fabric-matrix interface and fiber rupture. In this study, a perfect bond was considered for the interaction between the masonry column and the external reinforcement according to the experimental observations (calibration specimens). The parametric analysis allowed to evidence the influence of the mechanical and geometrical parameters on the structural performances of the FRCM-system in confining column.
21
Al-Lami, Karrar, Tommaso D’Antino, and Pierluigi Colombi. "Study of the Bond Capacity of FRCM- and SRG-Masonry Joints." CivilEng 2, no. 1 (January 10, 2021): 68–86. http://dx.doi.org/10.3390/civileng2010005.
Full textAbstract:
Fiber-reinforced cementitious matrix (FRCM) and steel-reinforced grout (SRG) have been increasingly applied as externally bonded reinforcement to masonry members in the last few years. Unlike fiber-reinforced polymer (FRP), FRCM and SRG have good performance when exposed to (relatively) high temperature and good compatibility with inorganic substrates, and they can be applied to wet surfaces and at (reasonably) low temperatures. Although numerous studies investigated the mechanical properties and bond performance of various FRCM and SRG, new composites have been developed recently, and their performance still needs to be assessed. In this study, the bond behavior of three FRCM composites and one SRG composite applied to a masonry substrate is investigated. Sixteen single-lap direct shear tests (four tests for each composite) are performed. The FRCM studied comprised one layer of carbon, PBO (polyparaphenylene benzobisoxazole), or alkali-resistant (AR)-glass bidirectional textile embedded within two cement-based matrices. The SRG composite comprised one layer of a unidirectional stainless-steel cord textile embedded within a lime-based matrix. The results show a peculiar bond behavior and failure mode for each composite. Based on these results, the behavior of the carbon and PBO FRCM is modeled solving the bond differential equation with a trilinear cohesive material law (CML).
22
Al-Lami, Karrar, Tommaso D’Antino, and Pierluigi Colombi. "Study of the Bond Capacity of FRCM- and SRG-Masonry Joints." CivilEng 2, no. 1 (January 10, 2021): 68–86. http://dx.doi.org/10.3390/civileng2010005.
Full textAbstract:
Fiber-reinforced cementitious matrix (FRCM) and steel-reinforced grout (SRG) have been increasingly applied as externally bonded reinforcement to masonry members in the last few years. Unlike fiber-reinforced polymer (FRP), FRCM and SRG have good performance when exposed to (relatively) high temperature and good compatibility with inorganic substrates, and they can be applied to wet surfaces and at (reasonably) low temperatures. Although numerous studies investigated the mechanical properties and bond performance of various FRCM and SRG, new composites have been developed recently, and their performance still needs to be assessed. In this study, the bond behavior of three FRCM composites and one SRG composite applied to a masonry substrate is investigated. Sixteen single-lap direct shear tests (four tests for each composite) are performed. The FRCM studied comprised one layer of carbon, PBO (polyparaphenylene benzobisoxazole), or alkali-resistant (AR)-glass bidirectional textile embedded within two cement-based matrices. The SRG composite comprised one layer of a unidirectional stainless-steel cord textile embedded within a lime-based matrix. The results show a peculiar bond behavior and failure mode for each composite. Based on these results, the behavior of the carbon and PBO FRCM is modeled solving the bond differential equation with a trilinear cohesive material law (CML).
23
Ferretti, Francesca, Andrea Incerti, Barbara Ferracuti, and Claudio Mazzotti. "FRCM Strengthened Masonry Panels: The Role of Mechanical Anchorages and Symmetric Layouts." Key Engineering Materials 747 (July 2017): 334–41. http://dx.doi.org/10.4028/www.scientific.net/kem.747.334.
Full textAbstract:
The use of fiber reinforced composite materials for the retrofitting of existing masonry buildings is investigated in this paper. Indeed, they represent a great alternative to traditional strengthening techniques for the improvement of the seismic performance of masonry walls. Focusing on the in-plane behavior of masonry, an experimental campaign is here presented with the objective of studying the efficiency of different strengthening solutions. Diagonal compression tests were conducted on single-leaf masonry panels reinforced with Fiber Reinforced Cementitious Matrix (FRCM) using different fibers typologies and layouts. Glass or carbon fiber grids embedded in a lime-based mortar matrix were applied on one or both sides of masonry panels, with or without mechanical anchorages. The comparison of the different strengthening techniques is analyzed in terms of failure mode, strength and ductility. The results are then discussed considering the provisions and design formula proposed for FRP strengthening by the Italian CNR Guidelines.
24
D'Antino, Tommaso, and Carlo Poggi. "Stress Redistribution in Glass Fibers of G-FRCM Composites." Key Engineering Materials 817 (August 2019): 520–27. http://dx.doi.org/10.4028/www.scientific.net/kem.817.520.
Full textAbstract:
Fiber reinforced cementitious matrix (FRCM) composites are increasingly adopted as a strengthening technique for existing masonry structures. Among the different fibers that can be employed in the reinforcing open-mesh textiles, which are embedded within cement- and lime-based matrices, glass fibers are gaining popularity due to their low price and promising performances observed so far. However, the stress redistribution between the glass fiber filaments within the textile is often uneven, which strongly affects the performance of the FRCM when subjected to external forces. In this paper, the stress redistribution between the glass fiber filaments is studied on the basis of tensile tests on a glass fiber textile left bare and impregnated with organic and inorganic matrices. The parameters studied are the fiber textile tensile strength and elastic modulus. Different systems, including the digital image correlation (DIC) technique, were employed to measure the specimen tensile strain. The results obtained shed light on the tensile strength of the glass textile, which is a key parameter in the design of glass FRCM strengthening.
25
de Carvalho Bello, Claudia Brito, Antonella Cecchi, Emilio Meroi, and Daniel V. Oliveira. "Experimental and Numerical Investigations on the Behaviour of Masonry Walls Reinforced with an Innovative Sisal FRCM System." Key Engineering Materials 747 (July 2017): 190–95. http://dx.doi.org/10.4028/www.scientific.net/kem.747.190.
Full textAbstract:
An experimental and numerical investigation on an innovative composite reinforced with sisal fibers for masonry strengthening is presented in this paper. A FEM numerical approach is also developed, based on diagonal compression test results, to simulate the shear in-plane response of unreinforced masonry panels (URM) and masonry strengthened with a Fibre Reinforced Cementitious Matrix (FRCM) composite system made with sisal fibers (RM-SISAL).
26
Baietti, Giulia, Tommaso D’Antino, and Christian Carloni. "Some Key Aspects in the Mechanics of Stress Transfer Between SRG and Masonry." Applied Sciences 10, no. 20 (October 19, 2020): 7303. http://dx.doi.org/10.3390/app10207303.
Full textAbstract:
The use of composite materials to strengthen masonry structures has become common practice within the civil engineering community. Steel-reinforced grout (SRG), which comprises high-strength steel fibers embedded in a mortar matrix, is part of the family of the fiber-reinforced cementitious matrix (FRCM) composites that represent a suitable alternative to fiber-reinforced polymer (FRP) composites for strengthening existing structures. Although studies on FRCMs have already reached a certain level of maturity, some key issues remain open, such as the role of matrix type and layout, substrate properties, and test rate. This paper focuses on some of these issues. The results of single-lap direct shear tests on masonry blocks strengthened with SRGs are presented to analyze the bond behavior between the composite material and the substrate. Four aspects are considered: (1) the change in the width of the SRG mortar matrix while keeping the width of the fiber sheet fixed; (2) the type of mortar used for the SRG; (3) the influence of the test rate, and (4) the type of substrate (i.e., concrete vs. masonry). The results obtained indicate the active role of the matrix layout and the importance of the test rate, encouraging further investigations to clarify these aspects.
27
Valdés, Monica, Giovanna Concu, and Barbara de Nicolo. "FRP Strengthening of Masonry Columns: Experimental Tests and Theoretical Analysis." Key Engineering Materials 624 (September 2014): 603–10. http://dx.doi.org/10.4028/www.scientific.net/kem.624.603.
Full textAbstract:
Structural rehabilitation involving upgrading of existing structures and buildings conservation has becoming increasingly important. In this paper an experimental campaign on natural stone masonry columns axially confined by fiber reinforced polymers (FRP) is presented and discussed. Two different FRP wrapping system have been used: CFRP (carbon-fiber-reinforced polymer) embedded in epoxy resin, and FRMC (fiber-reinforced-cementitious matrix) embedded in two layers of a special mortar acting as bonding agent. A comparison between the two systems has been carried out. Results show that the ultimate load, stiffness and ductility significantly increase compared with unreinforced columns. Pre-damaged columns strengthened with CFRP and FRCM recover their load bearing capacity and improve their ductility. In addition, experimental results have been compared to theoretical strength previsions provided by literature analytical models, and findings have been analyzed and discussed.
28
Tilocca, Anna Rosa, Andrea Incerti, Alessandro Bellini, and Marco Savoia. "Influence of Matrix Properties on FRCM-CRM Strengthening Systems." Key Engineering Materials 817 (August 2019): 478–85. http://dx.doi.org/10.4028/www.scientific.net/kem.817.478.
Full textAbstract:
During the last decades, widespread seismic events in the Southern European zone have significantly damaged the masonry built heritage. Designers and researchers studied different techniques to increase the performance of masonry panels subjected to horizontal actions due to seismic phenomena. In particular, two of the most common strengthening systems are Fiber Reinforced Cementitious Matrix (FRCM) and Composite Reinforced Mortar (CRM). These systems are usually applied on both surfaces of the load-bearing elements in order to increase their shear strength properties. This work aims at analyzing the effects of three different matrices, comparing FRCM and CRM systems applied on double-leaf masonry panels subjected to diagonal compression test in displacement control (ASTM E519). Compressive strength and thickness of the matrices applied on the masonry substrate were investigated in order to evaluate the relationship between the performance of matrices used within composite strengthening systems (FRCM or CRM) and the density of fiber grids adopted (basalt and glass). The mechanical characterization of the different strengthening systems was performed by means of tensile and bond tests on masonry prisms. Finally, the experimental results obtained were analyzed in terms of failure modes and maximum capacity attained by strengthened panels.
29
Calabrese, Angelo Savio, Pierluigi Colombi, and Tommaso D'Antino. "A Bending Test Set-Up for the Investigation of the Bond Properties of FRCM Strengthenings Applied to Masonry Substrates." Key Engineering Materials 817 (August 2019): 149–57. http://dx.doi.org/10.4028/www.scientific.net/kem.817.149.
Full textAbstract:
Existing masonry and reinforced concrete structures are characterized by a wide use of structural and non-structural masonry members such as structural walls, infill walls, arches, vaults etc. All these members are characterized by high vulnerability when subjected to seismic events, since unreinforced masonry has a negligible tensile strength. The use of fiber reinforced polymers (FRP) composites has become a common practice and it represents a light-weight, easy, fast, and non-invasive solution for rehabilitation of existing masonry structures. Fabric reinforced cementitious matrix (FRCM) are relatively newly developed composite materials, representing a valid alternative to FRP in strengthening and retrofitting of existing reinforced concrete and masonry structures. Despite of the numerous advantages guaranteed by the inorganic matrix, the bond-behavior between the fibers and the embedding matrix is still under investigation. Different set-ups have been proposed in the literature to study the bond behavior of FRCM composites. Among them, single-and double-lap shear tests are the most commonly used. In this paper, the bond behavior of a polyparaphenylene benzobisoxazole (PBO) FRCM composite applied to masonry elements is studied using a bending and a single-lap shear test set-up. The bond capacities obtained by the two set-ups are analyzed and discussed.
30
D'Antino, Tommaso, Jaime Gonzalez, Carlo Pellegrino, Christian Carloni, and Lesley H. Sneed. "Experimental Investigation of Glass and Carbon FRCM Composite Materials Applied onto Concrete Supports." Applied Mechanics and Materials 847 (July 2016): 60–67. http://dx.doi.org/10.4028/www.scientific.net/amm.847.60.
Full textAbstract:
In recent decades the growing need for strengthening and retrofitting existing structures has led to the development of innovative strengthening materials. Fibre reinforced composites have been shown to be an effective strengthening solution for flexural and shear strengthening and for confinement of axially/eccentrically loaded elements. Fibre Reinforced Cementitious Matrix (FRCM) composites, comprised of high-strength fibres and an inorganic matrix, are a newly-developed type of composite that has better resistance to high temperature and compatibility with the substrate than traditional fibre reinforced polymer (FRP) composites. This paper investigates the behaviour of FRCM composites comprised of a glass or carbon fibre net tested using single-lap direct-shear tests. Observations regarding the load response and failure mode of FRCM-concrete joints with different geometrical and mechanical characteristics are provided.
31
D'Anna, Jennifer, Giuseppina Amato, Jian Fei Chen, Giovanni Minafò, and Lidia La Mendola. "On the Use of Digital Image Correlation (DIC) for Evaluating the Tensile Behaviour of BFRCM Strips." Key Engineering Materials 817 (August 2019): 377–84. http://dx.doi.org/10.4028/www.scientific.net/kem.817.377.
Full textAbstract:
Fibre Reinforced Cementitious Matrix (FRCM) composites are becoming largely adopted for retrofitting masonry structures. These materials offer several advantages in comparison to Fibre Reinforced Polymer (FRP) composites, such as good resistance to fire and high temperatures, vapour permeability, possibility to be applied on wet surfaces, higher compatibility with the masonry substrate. However, the tensile behavior of FRCM materials is more complex compared to FRP composites, due to the limited tensile strength of the cement-based matrix. For this reason, FRCM materials require appropriate tensile characterization and, in this context, the use of non-conventional measurement systems, such as the Digital Image Correlation (DIC), can offer numerous advantages. This work presents an experimental study on the application of the DIC technique for the tensile characterization of Basalt Fibre Reinforced Cementitious Matrix (BFRCM) strips. Tensile tests were carried out on three series of specimens reinforced with one, two or three layers of basalt grid in order to investigate the effect of the reinforcement ratio on the tensile response of the composite strips. The test setup and the calibration of the DIC analyses are discussed. It is shown as the DIC allows obtaining detailed information on the tensile response, including the evaluation of the full strain field on the surface of the BFRCM strips and the location of cracks. Results are discussed also in terms of stress-strain curves and failure modes.
32
Alecci, Valerio, Francesco Focacci, Luisa Rovero, Gianfranco Stipo, Giovanni Mantegazza, and Mario de Stefano. "FRCM Composites for Strengthening of Brick Masonry Arches." Key Engineering Materials 747 (July 2017): 174–81. http://dx.doi.org/10.4028/www.scientific.net/kem.747.174.
Full textAbstract:
This paper examines the structural behavior of masonry arches strengthened at the intrados with fabric reinforced cementitions matrix (FRCM) composites. Textiles made of poliparafenilenbenzobisoxazole (PBO) and carbon fibers are considered. The experimental results are compared with those obtained on un-strengthened arches and arches strengthened with a carbon fiber reinforced polymer (C-FRP) composite. The tested arches are analyzed with the approach of the limit analysis of the collapse mechanisms.
33
Ombres, Luciano, Antonio Iorfida, and Salvatore Verre. "Confinement of Masonry Columns with PBO and Basalt FRCM Composites." Key Engineering Materials 817 (August 2019): 392–97. http://dx.doi.org/10.4028/www.scientific.net/kem.817.392.
Full textAbstract:
A new generation of composite materials in the form of Fiber Reinforced Cementitious Matrix (FRCM) was recently used to strengthen the masonry structures. Six small scale masonry columns were tested under monotonic concentric load until collapse; three columns were confined with PBO (short of polyparafenilenbenzobisoxazole)-FRCM jackets, two with basalt–FRCM jackets while an unconfined column was used as a control specimen. The masonry columns investigated have a rectangular cross section 250x250 mm among the overall length equal to 770 mm, and the corners were rounded to a radius of 20 mm. The analysis was conducted varying the confinement ratio i.e. the number of fabric layers for each FRCM system. Obtained results allow evidencing the effectiveness of the confinement and the effect n-layer on the structural response of the masonry columns.
34
Bellini, Alessandro, Marco Bovo, Andrea Incerti, and Claudio Mazzotti. "An Alternative Approach for FRCM Matrix Tensile Strength Evaluation." Key Engineering Materials 817 (August 2019): 365–70. http://dx.doi.org/10.4028/www.scientific.net/kem.817.365.
Full textAbstract:
Structural retrofitting with composite materials proved to be an effective technique for rehabilitation of degraded or damaged masonry and concrete buildings. Nowadays, Fiber Reinforced Cementitious Matrix (FRCM) composites are widely used as externally bonded strengthening systems thanks to their high performance, low weight and easiness of installation. Several experimental tests and numerical studies are currently available concerning the tensile and bond behavior of FRCM systems, but a debated and still open issue concerns the methods for the mechanical characterization of the mortar used as matrix within the strengthening system. The present paper analyses and compares different test methods for determining the matrix tensile strength. Pure tensile and flexural tests have been carried out on different mortar matrix samples. In order to evaluate which is the most suitable value to be considered for a correct interpretation and modeling of the composite system, the experimental results obtained through flexural tests on standard mortar specimens have been compared with the outcomes obtained from direct tensile tests on FRCM coupons. The present study represents only a first step for the definition of the most appropriate test method for the mechanical characterization of the matrix used within FRCM strengthening systems.
35
Crisci, Giovanni, Giancarlo Ramaglia, Gian Piero Lignola, Francesco Fabbrocino, and Andrea Prota. "Effects of the Mortar Matrix on the Flexural Capacity of Masonry Cross Sections Strengthened with FRCM Materials." Applied Sciences 10, no. 21 (November 8, 2020): 7908. http://dx.doi.org/10.3390/app10217908.
Full textAbstract:
The strengthening intervention strategies that exist for masonry buildings are based on the use of thin composites and are a recent activity used in structural engineering. Nowadays, mortar matrices are frequently found instead of epoxy resins, since the fiber reinforced cementitious matrix (FRCM) composites are more compatible with masonry than fiber reinforced plastic (FRP) ones. The mortar matrix in FRCM composites is not comparable to the epoxy resin, and therefore its contribution is different not only in traction but above all on the compression side. Due to its larger thickness, if compared to the epoxy resin, the impact of the mortar matrix on the flexural response of strengthened cross sections is not negligible. This paper aimed to investigate the influence of the contribution of the mortar matrix on the compression side on the flexural capacity of strengthened cross section. As such, p–m interaction domains and bending moment–curvature diagrams were evaluated to understand the influence of several mechanical properties of fiber and mortar matrices on FRCM efficiency, typical of real applications. Hence, the impact of several constitutive relationships of composites (linear and bilinear behavior) was considered for the structural analysis of the strengthened cross section. The presented results are all completely in a dimensionless form; therefore, independent of geometry and mechanical parameters can be the basis for developing standardized design and/or verification methodologies useful for the strengthening systems for masonry elements.
36
Di Tommaso, Angelo, Francesco Focacci, and Francesco Micelli. "Strengthening Historical Masonry with FRP or FRCM: Trends in Design Approach." Key Engineering Materials 747 (July 2017): 166–73. http://dx.doi.org/10.4028/www.scientific.net/kem.747.166.
Full textAbstract:
Over the past two decades, composite materials, in forms of Fiber Reinforced Polymers (FRP), have been widely spread worldwide in the field of civil and monumental construction. Design guidelines and provisions were developed and provided by national and international institutions. In the last years, a new generation of materials, named Fabric Reinforced Cementitious Matrix (FRCM) were introduced as strengthening devices for concrete and masonry structures. Their application in the field of historical masonry has grown as a result of the recent Italian earthquakes. In this paper, starting from a retrospective on what has been done in recent years in the field of FRP applications, insights will be discussed for future research and applications of FRP and FRCM in heritage buildings. Some differences between FRP and FRCM materials will be highlighted, in terms of fiber-matrix interface and delamination mechanisms. The different micromechanical behavior in terms of fracture energy will be highlighted, and the macro-mechanical implications in terms of ductility will be pointed out, as a first attempt to quantify this complex problem. By considering the last innovative and pioneering applications of FRP/FRCM in heritage buildings, criteria for structural enhancement will be shown and discussed. This is done with a special focus on the ability, shown by these new technologies, to inhibit failure mechanisms in masonry artifacts.
37
Turk, Ahmet Murat. "Seismic Response Analysis of Masonry Minaret and Possible Strengthening by Fiber Reinforced Cementitious Matrix (FRCM) Materials." Advances in Materials Science and Engineering 2013 (2013): 1–14. http://dx.doi.org/10.1155/2013/952497.
Full textAbstract:
This paper presents the analytical study on the dynamic response of a natural stone block masonry minaret of a historical mosque located in Istanbul, Turkey. A three-dimensional finite element model of the whole minaret, adjusted with former in situ ambient vibration test results, was used in order to get probable lateral displacements, stresses, and understanding of failure modes under seismic loading. Particularly, FEM has been used to evaluate the seismic safety of the minaret in present-day condition and after the application of a proposed strengthening method. In this method, by utilizing the fiber reinforced cementitious matrix (FRCM) material, the critical cross-sections were jacketed. The appearing damage for the bare minaret obtained from FEM analyses was located at the boot and transition part of the minaret. After FRCM material was wrapped around these critical cross-sections, the analytical results indicated that such method appears effective in terms of the seismic response. It also appears less invasive in terms of the conservation of historical heritage like minarets without causing aesthetic conflict on the existing structure when compared to other available techniques.
38
Donnini, Jacopo, Francesca Bompadre, and Valeria Corinaldesi. "Tensile Behavior of a Glass FRCM System after Different Environmental Exposures." Processes 8, no. 9 (September 1, 2020): 1074. http://dx.doi.org/10.3390/pr8091074.
Full textAbstract:
The use of Fabric-Reinforced Cementitious Matrix (FRCM) systems as externally bonded reinforcement for concrete or masonry structures is, nowadays, a common practice in civil engineering. However, FRCM durability against aggressive environmental conditions is still an open issue. In this paper, the mechanical behavior of a glass FRCM system, after being subjected to saline, alkaline and freeze–thaw cycles, has been investigated. The experimental campaign includes tensile tests on the fabric yarns, compression and flexural tests on the matrix and tensile tests (according to AC434) on FRCM prismatic coupons. The effects of the different environmental exposures on the mechanical properties of both the constituent materials and the composite system have been investigated and discussed. Ion chromatography analysis has also been performed to better understand the damage mechanisms induced by environmental exposures and to evaluate the ions’ penetration within the inorganic matrix. Alkaline exposure was shown to be the most detrimental for Alkali-Resistant (AR) glass fiber yarns, causing a reduction in tensile strength of about 25%. However, mechanical properties of the FRCM composite seemed not to be particularly affected by any of the artificial aging environments.
39
Bove, Martino, Anna Castellano, Aguinaldo Fraddosio, Jacopo Scacco, Gabriele Milani, and Mario Daniele Piccioni. "Experimental and Numerical Analysis of FRCM Strengthened Parabolic Tuff Barrel Vault." Key Engineering Materials 817 (August 2019): 213–20. http://dx.doi.org/10.4028/www.scientific.net/kem.817.213.
Full textAbstract:
This work focuses on an experimental and numerical study of a tuff barrel vault first damaged by differential vertical settlements of the abutments without rotations, then reinforced with a FRCM system composed by a fiber-reinforced mortar embedding a basalt fiber net, and finally subjected to a concentrated load on a generatrix (still ongoing). The geometry of the vault (polycentric near parabolic shape) and the masonry material (Apulian tuff) have been chosen in order to be representative of some masonry vaults common in rural constructions of Apulia region; also, a load representative of the infill weight has been applied during all the experimental tests. In parallel to the experiments, numerical simulations by a heterogeneous FE Abaqus model calibrated on the experimentally determined mechanical properties of materials have been performed. This model aims at reproducing the settlement phase and to accurately predict the load bearing capacity of the reinforced structure. To this aim, Concrete Damage Plasticity model has been used for modeling mortar joints and cementitious matrix, whereas tuff bricks have been assumed linearly elastic; finally, the basalt fiber net used in the FRCM reinforced has been described by suitable equivalent elasto-damaging trusses.
40
Kanakubo, Toshiyuki, Saki Echizen, Jin Wang, and Yu Mu. "Pullout Behavior of Bundled Aramid Fiber in Fiber-Reinforced Cementitious Composite." Materials 13, no. 7 (April 9, 2020): 1746. http://dx.doi.org/10.3390/ma13071746.
Full textAbstract:
The tensile performance of fiber-reinforced cementitious composite (FRCC) after first matrix cracking is characterized by a tensile stress–crack width relationship called the bridging law. The bridging law can be obtained by an integral calculus of forces carried by individual bridging fibers considering the effect of the fiber inclination angle. The main objective of this study is to investigate experimentally and evaluate the pullout behavior of a single aramid fiber, which is made with a bundling of original yarns of aramid fiber. The bundled aramid fiber has a nonsmooth surface, and it is expected to have good bond performance with the matrix. The test variables in the pullout test are the thickness of the matrix and the inclined angle of the fiber. From the test results, the pullout load–slip curves showed that the load increases lineally until maximum load, after which it decreases gradually. The maximum pullout load and slip at the maximum load increase as the embedded length of the fiber becomes larger. The pullout load–crack width relationship is modeled by a bilinear model, and the bridging law is calculated. The calculated result shows good agreement with the experimental curves obtained by the uniaxial tension test of aramid–FRCC.
41
Trapko, Tomasz. "The deformability of compressed concrete elements strengthened with FRCM composite materials." Budownictwo i Architektura 12, no. 1 (March 11, 2013): 163–70. http://dx.doi.org/10.35784/bud-arch.2188.
Full textAbstract:
In the paper the results of experimental studies performed on compressed concrete elements strengthened with composite fabric of FRCM (Fibre Reinforced Cementitious Matrix) technology are presented. In the studies the influence of temperature, the number of composite fabric layers and the length of ending overlap on the value and distribution of circumferential limit strains was analyzed.
42
Angiolilli, Michele, Amedeo Gregori, and Marco Vailati. "Lime-Based Mortar Reinforced by Randomly Oriented Short Fibers for the Retrofitting of the Historical Masonry Structure." Materials 13, no. 16 (August 6, 2020): 3462. http://dx.doi.org/10.3390/ma13163462.
Full textAbstract:
Recent seismic events prompted research to develop innovative materials for strengthening and repair of both modern and historic masonry constructions (buildings, bridges, towers) and structural components (walls, arches and vaults, pillars, and columns). Strengthening solutions based on composite materials, such as the Fiber Reinforced Polymers (FRP) or the Fiber Reinforced Cementitious Matrix (FRCM), have been increasingly considered in the last two decades. Despite reinforcement made of short-fibers being a topic that has been studied for several years from different researchers, it is not yet fully considered for the restoration of the masonry construction. This work aims to experimentally investigate the enhancement of the mechanical properties of lime-based mortar reinforced by introducing short glass fibers in the mortar matrix with several contents and aspect ratios. Beams with dimensions of 160 mm × 40 mm × 40 mm with a central notch were tested in three-point bending configuration aiming to evaluate both the flexural strength and energy fracture of the composite material. Then, the end pieces of the broken beams were tested in Brazilian and compressive tests. All the tests were performed by a hydraulic displacement-controlled testing machine. Results highlight that the new composite material ensures excellent ductility capacity and it can be considered a promising alternative to the classic fiber-reinforcing systems.
43
Kim, Min-Jun, Hyeong-Gook Kim, Yong-Jun Lee, Dong-Hwan Kim, Min-Su Jo, and Kil-Hee Kim. "Evaluation of Bond Properties of a Fabric-Reinforced Cementitious Matrix for Strengthening of Concrete Structures." Applied Sciences 10, no. 11 (May 29, 2020): 3767. http://dx.doi.org/10.3390/app10113767.
Full textAbstract:
In the present study, pull-out and pull-off tests were conducted to examine the bond strength between an inorganic cement adhesive (hereinafter referred to as the “matrix”) and a textile, which composed a fabric-reinforced cementitious matrix (FRCM). The matrix was developed by mixing slag and short fibers in an attempt to improve the alkali resistance and compressive strength. The developed matrix was examined with regard to its alkali resistance, water resistance, and void distribution. Bond tests were conducted in two parts: a pull-out series and pull-off series. The type of textile (carbon or basalt) and the weaving methods were selected as test parameters. These tests were performed in accordance with the methods described in ISO10406-1 (pull-out) and ASTM C1583 (pull-off). The test results showed that the developed matrix was superior to existing mortar methods in terms of alkali resistance, water resistance, and compressive strength. Additionally, the FRCM in which carbon textiles were used exhibited excellent bond performance.
44
A. Mousa, Mohammed. "Tensile Behavior of Alternative Reinforcing Materials as Fiber Reinforced Cementitious Mortar FRCM." International Journal of Engineering & Technology 7, no. 4.20 (November 28, 2018): 239. http://dx.doi.org/10.14419/ijet.v7i4.20.25933.
Full textAbstract:
The adoption of new reinforcing and retrofitting materials provide an alternative and affordable techniques that can be utilized in low-income communities. FRCM is comprised of a broad spectrum family of reinforcing materials such that it allowed utilizing affordable local alternatives such as fishing net FN and welded wire steel mesh WWSM. The composite effectiveness stems from the compatible inorganic matrix properties which have similar properties to the substrate unlike other composites such as FRP. The tensile response of FN and WWSM and their mortar composites has been experimentally studied to characterize their strength, deformation, and the bonding between the reinforcement and the mortar. Experimental investigations on dog-bone composites specimens with their materials samples subjected to uniaxial tensile load were performed. The experimental campaign included testing 12 composite specimens taking into account multiple parameters like material, thread thickness, and the layer effect. The results show comparable strengths and high deformation capacity (12.5 times) of FN to the WWSM. Finally, the SEM imaging shows a well-impregnation between the mortar and the reinforcement of both materials. The tensile response of the composite emphasizes its potential as structural retrofitting and hazard mitigation technique for local builders and house owners in developing countries.
45
Gonzalez-Libreros, Jaime, Mariano Angelo Zanini, Flora Faleschini, and Carlo Pellegrino. "Confinement of low-strength concrete with fiber reinforced cementitious matrix (FRCM) composites." Composites Part B: Engineering 177 (November 2019): 107407. http://dx.doi.org/10.1016/j.compositesb.2019.107407.
Full text
46
Donnini, Jacopo, Giovanni Lancioni, Tiziano Bellezze, and Valeria Corinaldesi. "Bond Behavior of FRCM Carbon Yarns Embedded in a Cementitious Matrix: Experimental and Numerical Results." Key Engineering Materials 747 (July 2017): 305–12. http://dx.doi.org/10.4028/www.scientific.net/kem.747.305.
Full textAbstract:
The use of inorganic cement based composite systems, known as Fiber Reinforced Cementitious Matrix (FRCM), is a very promising technique for retrofitting and strengthening the existing masonry or concrete structures. The effectiveness of FRCM systems is strongly related to the interface bond between inorganic matrix and fabric reinforcement, and, since the major weakness is often located on this interface, the study of stress-transfer mechanisms between fibers and matrix becomes of fundamental importance.FRCM are usually reinforced with uni-directional or bi-directional fabrics consisting of multifilament yarns made of carbon, glass, basalt or PBO fibers, disposed along two orthogonal directions. The difficulty of the mortar to penetrate within the filaments that constitute the fabric yarns and the consequent non-homogeneous stress distribution through the yarn cross section makes difficult to access the characterization of the composite material. The use of polymer coatings on the fibers surface showed to enhance the bond strength of the interface between fibers and mortar and, as a consequence, to improve the mechanical performance of the composite. The coating does not allow the mortar to penetrate within the filaments while is able to improve the bond between the two materials and to increase the shear stress transfer capacity at the interface.An experimental session of several pull out tests on carbon yarns embedded in a cementitious matrix was carried out. Different embedded lengths have been analyzed, equal to 20, 30 and 50 mm. The carbon yarns object of this study were pre-impregnated with a flexible epoxy resin enhanced with a thin layer of quartz sand applied on the surface.A variational model was proposed to evaluate the pull-out behaviour and failure mechanisms of the system and to compare numerical results to the experimental outcomes. Evolution of fracture in the yarn-matrix system is determined by solving an incremental energy minimization problem, acting on an energy functional which account for brittle failure of matrix and yarn, and for debonding at the yarn-matrix interface. The model was able to accurately describe the three phases of the pull-out mechanism, depending on the embedded length.
47
Ferretti, Francesca, Andrea Incerti, Anna Rosa Tilocca, and Claudio Mazzotti. "Grout Injection Effect on the Shear Behavior of FRCM Strengthened Stone Masonry Panels." Key Engineering Materials 817 (August 2019): 552–59. http://dx.doi.org/10.4028/www.scientific.net/kem.817.552.
Full textAbstract:
During the last decades, several seismic phenomena have shown the high vulnerability of existing stone masonry structures subject to horizontal actions. Innovative composite materials, such as Fiber Reinforced Cementitious Matrix (FRCM), can be adopted for the retrofitting of masonry structures. The use of these innovative FRCM systems is usually combined with a more traditional retrofitting technique: grout injection. It allows to restore or improve the transversal connection between wall leaves, ensuring a monolithic behavior of the structural element. The objective of this research was to analyze the effect of the quality of the grout injection on the shear response of FRCM strengthened stone masonry panels. Results from an experimental campaign, where stone masonry specimens were subject to diagonal compression tests, are therefore presented in this paper. Two samples were subject to grout injection and one of them was strengthened with Steel Reinforced Grout (SRG). Comparisons between the experimental results showed that grout injection alone, if correctly executed, could determine a significant improvement in the shear capacity of masonry panels. The application of the FRCM strengthening system could further enhance the behavior of the samples, especially influencing the failure mode. Comparisons with analytical formulations for the evaluation of the capacity of strengthened walls are also presented.
48
Urso, Santi, Houman A. Hadad, Chiara Borsellino, Antonino Recupero, Qing Da Yang, and Antonio Nanni. "Numerical Modelling of FRCM Materials Using Augmented-FEM." Key Engineering Materials 817 (August 2019): 23–29. http://dx.doi.org/10.4028/www.scientific.net/kem.817.23.
Full textAbstract:
The use of externally-bonded composite materials for strengthening and rehabilitation of existing structures is among the most popular reinforcement techniques. Technologies, such as Fabric Reinforced Cementitious Matrix (FRCM) have been recently developed to address some of the issues of Fiber Reinforced Polymers (FRP), such as sensitivity to elevated temperatures and UV, impermeability, restricted application in presence of moisture or uneven substrate. For a detailed strengthening design with FRCM composites, the mechanical properties of the materials are required. Analytical models in literature discuss the interaction between the FRCM matrix and fabric using a fracture mechanics approach. These analytical laws were simplified using a trilinear curve in which a constant branch correlated to the friction is added. In the United States, “Acceptance Criteria AC434” includes the test methods to evaluate the mechanical properties of the FRCM through a direct tensile test which uses clevis grips. The material characterization per AC434 is in harmony with ACI 549.4R design guidelines. This study deals with the analysis of FRCM materials using 2D Augmented-Finite Element Method (A-FEM) approach. Constitutive material behaviors were used to implement on A-FE model, which can predict the failure modes of the composite material. The damage of the mortar was described by a trilinear curve, and the number and position of the cracks were fixed preliminarily. The fabric was modelled as a continuum layer attached to the mortar with no-thickness cohesive elements. The cohesive law between fabric and mortar was taken from the literature. The tensile test on the FRCM coupon with one layer of fabric was numerically modeled and compared to the experimental stress-strain curves. Results show that the numerical curves matched the experimental ones and capture the three branches of the FRCM constitutive law as well as the failure mode. This modelling tool will allow researchers to predict the constitutive law of an FRCM mater
49
Rizzo, Valeria, Antonio Bonati, Francesco Micelli, Marianovella Leone, and Maria Antonietta Aiello. "Influence of Alkaline Environments on the Mechanical Properties of FRCM/CRM and their Materials." Key Engineering Materials 817 (August 2019): 195–201. http://dx.doi.org/10.4028/www.scientific.net/kem.817.195.
Full textAbstract:
Fabric Reinforced Mortar (FRCM) used as Externally Bonded Reinforcements (EBR), provide a sustainable solution for retrofitting and repair of existing masonry structures. They are commonly made by fibrous meshes embedded in a cementitious/hydraulic lime matrix. This technique represents a valid alternative to the well-known FRP (Fiber Reinforced Polymer) composites, which show some limitations in heritage masonry applications. In this scenario, a new system known as CRM (Composite Reinforced Mortar) has been developed in the last years. In this system, a pre-cured FRP grid is utilized as internal reinforcement in a mortar layer. The system reproduces the traditional technique of reinforced plaster, where the steel grid is substituted by a non-metallic one. In masonry applications high compatibility with the substrate, sustainability and removability are commonly required in heritage construction. These goals are not easily achieved by using fibers immersed into a polymeric resin. Moreover, the inorganic matrix ensures the transpiration of substrates and consequently a higher durability of the whole strengthened system is expected. On the other hand, the recent use of these new materials in civil engineering needs appropriate design guidelines. The proposed paper focuses attention on the initial results of a large experimental study on the durability of FRCM/CRM systems and their single components (dry glass fibers, resin, pre-cured FRP grid and mortar). In particular, the influence of three alkaline environments solutions was studied. Exposure conditions were stressed by increasing the temperature of the three aqueous solutions. The mechanical retention of tensile properties was measured by performing direct tensile tests after different exposure times.
50
Leone, Marianovella, Valeria Rizzo, Francesco Micelli, and Maria Antonietta Aiello. "Experimental Analysis on Bond Behavior of GFRCM Applied on Clay Brick Masonry." Key Engineering Materials 747 (July 2017): 542–49. http://dx.doi.org/10.4028/www.scientific.net/kem.747.542.
Full textAbstract:
External bonded reinforcements (EBR), made by fibrous meshes embedded in a cementitious/hydraulic lime mortar, are getting a great deal of attention, mostly for strengthening, retrofitting and repair existing structures. In this context, the interest versus the FRCM (Fiber Reinforced Cementitious Matrix) is growing. The mechanical performance of these mortar-based reinforcements is not well known at the date and it needs to be investigated in terms of bond and tensile strength, strain and stiffness, in relation to the type of both substrate and fibers. The present work reports the results of an experimental study, still in progress, on different pre-cured GFRP grids embedded in inorganic matrices and applied on clay brick masonry. First, the mechanical properties of both pre-cured GFRP grid and GFRCM reinforcements were obtained through tensile tests. Then, the experimental investigation on bond behavior was carried out by direct shear bond test. The test results were collected and processed to evaluate bond strength, failure mode, load-slip relationship.