In the present study, tensile tests were carried out to investigate the tensile behaviors of textile reinforced mortar (TRM) composite specimens. The TRM specimens were composed of one layer of carbon fibers, as the reinforcement, and aluminum cement‑based mortar, as the matrix. The primary parameter of the test specimens was the anchorage method, which was newly developed to improve the tensile behavior of the composite: spreading the ends of fiber filaments, reinforcing the ends of fiber filaments using glass fiber reinforced polymer tabs or steel rebars, and coating the ends of fiber filaments with aluminum oxide powder. From the test results, it was found that most TRM specimens using developed anchorage methods exhibited ductile behavior. Moreover, the use of the developed anchorage methods could increase the cracking strength and peak strength of the composite specimens up to 66.1 and 97.9%, respectively. The failure mode of the test specimens was governed by a partial rupture of carbon fibers, except for the BASE specimen and specimen reinforced with steel rebars. Finally, the tensile stress–strain relationship of TRM speci‑ mens was idealized as bilinear stress–strain response curves following the guidance specified in ACI 549.4R‑13. Keywords: tensile test, carbon fibers, aluminum cement, textile reinforced mortar, anchorage
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The use of carbon textile reinforced mortar (CTRM) offers an innovative alternative for strengthening measures by combining the advantages of light glued CFRP-stripes and the better bond characteristics of an additional concrete layer. Two possible fields of application were investigated and described in the paper: A considerable increase of the shear fatigue strength can be obtained by strengthening the web with CTRM. Furthermore, the static shear capacity also increases considerably due to the CTRM-strengthening, which could also be shown for bridge deck slabs that are CTRM-strengthened in the tension zone. Within the scope of further experimental investigations, the strengthening method is to be optimized. In addition to experimental investigations, a more detailed investigation is required regarding the actual design checks of beams and slabs strengthened with CTRM.
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7. A formula proposed by fib 2010  was used to predict the debonding stress in FRP reinforced for those specimens failed due to debonding of FRP from concrete substrate. This formula was also used to predict the debonding stress of TRM reinforce- ment for those specimens that have same failure mode (i.e. debonding). It was found that this formula is in a good agree- ment with the effective stress calculated based on the experi- mental results providing that TRM properties are obtained from coupon tests. The above-mentioned conclusions should be treated carefully. They are based on a limited number of tests on half-scale beams and specific type of textile fibre materials. More research is required including different types of textile materials and full-scale beams. This would also help to confirm the reliability of existing design models for FRP or the develop- ment of new reliable ones.
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In the case of the post-damage strengthened wall having a small window opening the strategy applied was based on TRM using MapeGrid C170carbon fiber grid and a surface type of anchorage using MapeWrap S Fiocco, a high-strength steel fiber cord. The strategy applied intended to increase the initial load bearing capacity of the element. After repairs, the surface of the wall was polished, 16 mm holes were drilled for the steel fiber cord anchorage, the corners of the opening were rounded about 20 mm and the surface of application was vacuum-cleaned. The cracks from the experimental test of the unstrengthened specimen were injected with epoxy resin (Epojet) using Sika mechanical injection packers, MPS type, 115 mm length. In this case the mortar for the TRM system was Planitop HDM, a two-component, high-strength, cement-based mortar with fine-grained aggregates, special admixtures and synthetic polymers (blended with a liquid, giving high bonding strength. The material consumption here comprised 15 mechanical packers, 2.5 kg epoxy resin for crack injection, 7.95 m steel fiber cord, 6 kg of resin for cord preimpregnation, 6 kg of resin for cord fixing through wall, 23.40 m 2 of carbon fiber grid and 396.5 kg component mortar
The mortar used as Textile Reinforced Mortar systems was BS 5F-U, manufactured by THERMAX Limited. BS 5F-U is a one component thixotropic corrosion resistance fiber reinforced polymer modified repair mortar. In order to determine the compressive strength of mortar, Total 6 cubes (100 x 100 x 100mm) were prepared and then tested under compression at 28 days. The average compressive strength of concrete at 28 days was 22.38 N/mm 2 . The mortar datasheet provided by the
when buildings are to be adaptively reused, it is necessarily required to strengthen the load-bearing structure. If such renovation work is aimed at adaptive reuse, this can often result in higher loads than permitted by the original design. The dominating technology to strengthen buildings is still steel reinforcement. But, this technology significantly increases the dimension of the structure as well as the load. Nowadays, instead of using ordinary steel reinforcement, researchers are introducing and trying out many methods. Recently, textile reinforcement has been introduction in the construction industry as a viable alternative strengthening material, to circumvent problems associated with FRP. The effectiveness of using textile-reinforced mortar as an innovative technique to improve the shear response of reinforced concrete beams has been investigated. The paper comprised of shear strengthening of shear deficient beams using Carbon and Basalt textile reinforced mortars. Test variables of this study were the matrix type namely cementitious mortar and pozzolanic mortar, wrapping configuration viz. U-wrap and Full-wrap and number of layers of textile reinforced mortar layers.
similar fle xu ral stress-deflection behavior in the conventional way of the composites of TRC. The conventional behavior of TRC concrete is conducted in three stages. The first stage represents the linear uncracked state where the cementitious matrix takes the load. Then, as the load increases, the stress transfers from the ce mentitious matrix to the te xtile, which is represented by the mu lti-c racking process of the matrix. At the point or stage where the first crack takes the p lace is called the transition point. Then, the specimens continue to undergo a multi-crac king process, in which all o f the stresses are transferred fro m matrix to te xtile. At this stage, the textile is only carrying until it fa ils by rupturing or by slipping . In Fig. 8 – 10 it can be seen that the fle xural stress -deflection curves greatly depend on the type of mesh size of the reinforc ing carbon text ile. The specimens with a te xt ile of smaller mesh size have higher fle xu ral strength than those with te xt ile of b igger mesh size, due to more d istribution of the yarns in the same thickness size o f co mposite specimens. Furthermore, at the mu ltic racking-formation state, the stiffness of co mposite thin p lates with carbon te xtile of 12x16 mm aperture size is stronger and that can be seen on the crack-widening state in Fig. 8, 9, 10, and 15. Fro m the results obtained, it is apparent that the use of a carbon mesh with an aperture size of 16x12 mm increases ultimate bending strength by 673.65%; a carbon mesh with an aperture size 25 ×25mm increases ultimate bending strength by 258.23% and a carbon mesh with an aperture size 3× 37 mm increases ultimate bending strength by 205.37% co mpared to nonreinforced reference specimens. However, mid -span deflection capacity at the average peak load of the specimens with three different mesh sizes is similar 10.34 mm, 10.25 mm and 10.10 mm, respectively (see Fig. 12 and 13).
This paper presents the development and technological implementation of textile reinforced concrete (TRC) shells with integrated functions, such as il- lumination and light control. In that regard the establishment of material, structural and technological foundations along the entire value chain are of central importance: From the light-weight design idea to the demonstrator and reference object, to the technological implementation for the transfer of the research results into practice. The development of the material included the requirement-oriented composition of a high-strength fine grained con- crete with an integrated textile reinforcement, such as carbon knitted fabrics. Innovations in formwork solutions provide new possibilities for concrete constructions. So, a bionic optimized shape of the pavilion was developed, re- alized by four connected TRC-lightweight-shells. The thin-walled TRC-shells were manufactured with a formwork made of glass-fibre reinforced polymer (GFRP). An advantage of the GFRP-formwork is the freedom of design con- cerning the formwork shape. Moreover, an excellent concrete quality can be achieved, while the production of the precast concrete components is simple and efficient simultaneously. After the production the new TRC-shells were installed and assembled on the campus of TU-Chemnitz. A special feature of the research pavilions are the LED light strips integrated in the shell elements, providing homogeneous illumination.
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Abstract: This paper presents the findings of an investigation on the compressive strength properties of kenaf fiber composite mortar. Water–retted kenaf fibers were used as reinforcement in cement mortar. Fiber contents of 1%, 2% and 3 % (by weight of cement) with varying lengths of 10mm, 20mm and 30mm were used to produce 50mm mortar cubes. The Composite mortars were cured in water for 3, 7, 14, 21, and 28days. A total of 150 mortar cubes were used for the study. Density, water absorption and compressive strength tests were conducted on the composite mortar. Regression analysis was carried out on the compressive strength results using Minitab 15. The results showed that water absorption and density of the composite mortar increased as the volume of fiber and length increased. Compressive strength decreased with increasing fiber volume and length. However, there was increase in compressive strength of between 0.21%-22.3% for composite mortar containing 1-3% volume of fiber with 10mm fiber length. The fitted regression model showed a perfect relationship (R 2 =84.5%) between compressive strength, fiber volume, fiber length and curing age. Therefore, fiber volume, fiber length and curing are useful predictors of the selected model. Model adequacy test reveals that the fitted regression model is highly adequate. There was no statistically significant difference in the compressive strength of the control samples and those containing 1-3% fiber volumes with fiber length of 10mm.
In two tables above is the proportion for 1 m³ of mortar for both the control samples and the mixtures that use stone powder and reinforced fiber. In Table 6 is the amount of cement, water and sand for all samples. The symbol M300-0 is the control sample with the designed strength of 30 MPa without reinforced fiber and stone powder. The symbol C, W and S respectively stand for the amount of cement, water and sand with the unit of C, S is kg/m³ and the unit of W is l/m³. In Table 7 are the samples that use stone powder and reinforced fiber with the amount of cement, water and sand like the controlling. Those samples are added stone powder and reinforced fiber, the symbol GF and CP in the table represent the amount of glass fiber and stone powder in kg/m³. About the symbol of the samples, each symbol has 2 numbers with the first number (a) is the amount of reinforced fiber in % and (b) the second number is the amount of stone powder also in %. This percentage is then converted to the corresponding weight (kg/m³) in the column of GF and CP.
Engineer we all know that Concrete is strong only in Compression and weak in Tension. In order to increase the Tensile strength of the Concrete, it is being reinforced with steel, which unfortunately also has the drawback of being susceptible to corrosion and fatigue. It will further increase the maintenance and repair cost of the structure. And it is clear that we urgently need high performance construction materials to adequately meet our needs. An innovative concept to eliminate these drawbacks is the textile reinforcement of concrete. For past many years leading scientists have been working with the idea of improving the world of concrete by using high performance fibres, developing so called “Textile Reinforced Concrete (TRC)”. The objective of this project is to study the various properties of Textile Reinforced Concrete (TRC). AR-Glass fibre mesh of 145 GSM is used. Specimens were casted with and without the fibres in the range of increase of fibre layers of 3, 4 and 5. Tests were conducted to study the Flexural strength of the beam. Beam specimens were casted using the 500mm×100mm×100mm beam mould. Among 4 beams casted, 3 were casted with fibre mesh and the another beam were casted without fibre mesh i.e. PCC beam. The tests were conducted by the method of three point loading system on the beam. And the interaction between the Cementitious Matrix and the Textile fibre mesh were determined. The results are compared between Textile Reinforced Concrete (TRC) and the Conventional Concrete. In which the PCC beam shows the Modulus of Rupture value as 7.75 N/mm 2 ,
ABSTRACT:Reinforced concrete beams are the important structural element that transmit the load from slab, wall to columns. Due to increasing serviceability requirement and poor construction practice in the past, there is a need to strengthening of beam to resist sudden failure against shear. In this paper, the effectiveness of textile-reinforced mortars (TRMs), for increasing the shear resistance of reinforced concrete beams, is to be investigated experimentally. TRM is a combination of textile bonded to RC member using cementitious mortar. The strength of TRM depends on tensile strength of textile and bonding strength of mortar. Textiles comprise of fabric meshes made of long woven, knitted or even unwoven fiber rovings in at least two (typically orthogonal) directions. TRMs may be considered as an alternative to fiber-reinforced polymers (FRP), providing solutions to many of the problems associated with application of the latter without compromising much of the performance of strengthened members. In the present study, a new type of textile (nylon-based textile) is used as strengthening material. The variation in strength with orientation of fiber and number of layers were studied.
Based on the results of the experimental tests, Abaca fiber-reinforced mortar have a high potential for retrofitting Unreinforced Masonry houses, especially in developing countries. FRM wallets by Abaca fiber-reinforced mortar showed a slightly higher strength because using Abaca fiber as reinforcement in cement composites does not contribute to increasing the strength and bigger deformation capacities than those of URM wallets. FRM with longer fiber (fiber length 80 mm) showed the highest strength as of 4.0 kN and also biggest ductility up to 45 mm, compared to URM and FRM with shorter fibers and FRM with fibers longer than 80 mm.
Flexural strength of a concrete is a measure of its ability to resist bending .The flexural strength results of concrete having addition of 0%, 1%, 2% and 3% textile fabric fibres are presented in Figure 4. The flexural strength generally increases with increase in curing age. At 7 days, increase in the fibre content increases the flexural strength from 3.57 N/mm 2 at 0% to 3.94 N/mm 2 at 1%; 4.12 N/mm 2 at 2% and to 4.5 N/mm 2 at 3% fibre content. At 14 days, there was an increase from 3.82 N/mm 2 , 4.05 N/mm 2 and 5.58 N/mm 2 at 0%, 1% and 2% fibre contents respectively, and then there was a decrease to 4.61 N/mm 2 at 3% fibre content. The trend was similar at 28 days, with an increase from 5.18 N/mm 2 , 5.37 N/mm 2 and 6.41 N/mm 2 at 0%, 1% and 2% fibre contents respectively, and decrease to 5.66 N/mm 2 at 3% fibre content. The increase in flexural strength indicates that the bonding within concrete increases by using textile fabric fibres. Thus helps in the reduction of cracks and enhances durability.
This section presents the result of an axial compression load test of reinforced wallettes fabricated using wood-wool cement panel bonded with normal sand cement mortar. The axial compression load capacity is a significant parameter in order to investigate the actual behaviour of wall under the action of gravity load on the building . The test results can be used as an indicator to determine the maximum vertical load that can safely carry by the walls and its potentiality as the load bearing wall system can be drawn . The reinforced wallettes without surface plaster (NPR) and plastered with 16 mm thickness of mortar (PR) have been observed in term of maximum load carrying capacity, load-vertical displacement behaviour and failure mode of each type of wallettes. A summary of maximum load and displacement at the maximum applied load of NPR and PR are shown in table 3.
dry wall construction has evolved from the traditional Khath-Khuni construction of Himachal Pradesh in which involves the construction technique with wooden members laid horizontally between infill materials generally stone, shingles etc. Due to unavailability of timber these days, an alternative sustainable technique is developed using cement-sand mortar sandwich panels laid in horizontal layers and reinforced galvanized steel wire mesh with provision for expansion joints.In eastern parts of India like Assam, Meghalaya, Tripura, and the rest of the North East, the use of bamboo has been an integral part of the cultural, social, economic traditions of these regions. A mature, cured bamboo of the right species can last a lifetime. Bamboo is used extensively for walls, roof trusses and floors in traditional construction methods. This is because bamboo is available in abundance and also easy to use.
and post installed bars, conducted in the Europe under provisions established by EOTA and in the U.S using ICC-ES. Paper has explained key points such as bond strength, the viability of adhesive delivery system, corrosion resistance and response to tension loading under splitting-critical conditions where shear lag is important. The assessment process, recommendations for harmonization and improvements are also discussed. With the development of new bonding materials, systems may result with significance differences in load-displacement response, bond or splitting test to address shear lag for long embedment as per AC308 is advisable and should be added in Eurocode. However, paper concludes that product could be designed and qualified in accordance with EAD330087 as its performance in cracked concrete is potentially unconservative.Giovacchino Genesio, Roberto Piccinin, John Silva (2017): Paper compares design methods based on Eurocode 2 and ACI 318. It also discusses some case studies where post installed rebar systems are used for the moment resisting connections. Challenges and new opportunities related to post installed connections are discussed. Paper shows multiple methods which could be adopted to satisfy the design requirements of real reinforced concrete moment resisting connections. Paper highlights strong need for a unified approach capable of merging reinforcing to concrete theory.Christph Mahrenholtz, Rolf Eligehausen, Hans-Wolf Reinhardt (2015): Paper highlights the interrelationships that are required for design between material strength parameters. Paper provided the methods of rebar building as cast-in or post installed end anchorage as per EN1992-1 and as CEN / TS 1992-4 bonded anchors. The comparison of both techniques is made using an illustration
In this research, sisal is being used in concrete. Thereby, the mechanical properties such as compressive strength, split-tensile strength, and modulus of rupture of M40 grade concrete and by varying the dosage of fibre content from 0.1%, 0.2%, 0.3%, 0.4%, and 0.5%, by volume of cement with optimum length of 35mm obtained from literature review, were found. The optimum dosage of sisal fibre was found to be 0.3%. The flexural behaviour of reinforced concrete beams with 0.3% sisal fibre was compared with conventional concrete properties of M40 grade.
The test conducted was a cyclic loading test on Reinforced Concrete and textile reinforced concrete beams to find stability points in which the loading started at zero loads and increased to point coinciding approximately with envelope load- deflection curve. The incremental load and deflection were chosen so that the loading curve, in each cycle attained the envelope curve. This is monitoring the incremental load up to yield and incremental deflection after yield in each cycle. The analytical study on the beam is carried out by the application of lateral force. The finite element model is analyzed and the displacement results are observed under half cyclic loading. In the finite element modeling, defining the property is an important process. Defining the property means, defining the material and section properties. Under this section the various fibre properties are applied.
The use of ﬁ ber reinforced polymers (FRP) as externally bonded (EB) reinforcement in shear strengthening of RC members has become very popular over the last two decades. Following the studies of Trianta ﬁ llou 1998  and Khalifa et al.  a big effort was made by researchers worldwide to further investigate or even improve this technique [i.e.3 e 9]; with all the results showing the high effectiveness of using EB FRP in shear strengthening of RC beams. However, the FRP strengthening technique has a few drawbacks mainly associated with the use of epoxy resins, namely high cost, poor performance in high temperatures, inability to apply on wet surfaces, as discussed in Ref. .
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