Cementitious Composite Panels Research Articles

Corrigendum to “Semi-dry technology-mediated coir fiber and scots pine particle-reinforced sustainable cementitious composite panels” [Constr. Build. Mater. vol. 305 (2021) 124816

Corrigendum to “Semi-dry technology-mediated coir fiber and scots pine particle-reinforced sustainable cementitious composite panels” [Constr. Build. Mater. vol. 305 (2021) 124816

Experimental and numerical investigations of hybrid-fibre engineered cementitious composite panels under contact explosions

In this study, the blast response of hybrid-fibre engineered cementitious composite (HFECC) panels with 1.75% polyvinyl alcohol and 0.58% steel fibres (by volume) is experimentally and numerically evaluated for the first time. For blast testing, HFECC and normal reinforced concrete (NRC) panels were tested under contact explosions generated by Plastic Explosive 4 (PE4) on a demolition range. The crater diameter, spalling diameter and fragment size were measured and compared. The averaged crater and spalling diameters of the NRC panels were 173.55 mm and 272.87 mm, respectively, while those of the HFECC panels were 91.16 mm and 178.93 mm, respectively. The fragment size of the HFECC panels was larger than 19 mm, whereas the fragments of the NRC panels had a wide size distribution ranging from < 1.7 mm to > 19 mm. An effective finite element model is also developed to reproduce the responses of the HFECC and NRC panels under blast loads. In the numerical model, a dynamic increase factor formula newly developed by the authors is incorporated to describe the rate sensitivity of HFECC in tension. A particle-based approach is employed, for the first time, to explicitly model the blast load applied on the concrete panels. The efficiency and accuracy of the numerical model are validated by comparing the numerical prediction with the experimental data. The validated model is then used to explore the blast resistance of a reinforced HFECC panel. It is found that the crater and spalling diameters obtained for the reinforced HFECC panel are decreased by 53.6% and 41.1% compared with those of the NRC panel. The damage distribution in the reinforced HFECC panel becomes less localised with the increase of the ductility of HFECC. The numerical results also show that the blast resistance of the distal surface relies more on the ductility of the matrix than that of the proximal surface.

Semi-dry technology mediated lignocellulosic coconut and energy reed straw reinforced cementitious insulation panels

Sustainable cementitious composite panels are gaining interest as efforts to reduce environmental burdens increase. This study investigated the possibilities and reinforcement effects of developing composite panels from coconut husk derived materials (CM) and reed straw (RS) particles in the presence of Ordinary Portland cement (OPC). Five composite panels with 1200 kg/m3 densities and 400 × 400 × 8 mm3 dimensions were produced. The proportion of lignocellulosic materials for energy reed and coconuts were 100:0, 60:40, 50:50, 40:60 and 0:100%, respectively. Other ingredients like OPC, Na2SiO3, and cement stone were kept constant. The panels were produced by utilizing energy efficient semi-dry technology, a novel fabrication technology that requires less water to make the slurry. The investigations – thermal conductivity, mechanical, physical, FTIR (Fourier transform infrared spectroscopy) and morphological – were conducted after 28 days of curation in a standard laboratory atmosphere. The test obtained the following results: the thermal properties of cementitious coconut and reed panels show that the thermal conductivity of the mixture expresses the excellent insulating properties of the panels. The thermal conductivity coefficient ranged from 0.11 to 0.15 W/(mK), with reed-only boards attaining superior values. Mechanical properties such as flexural strength and internal bonding strength showed an increasing trend as the amount of coconut increased. The panel containing coconut materials only achieved the best values – 5.13 MPa (flexural strength) and 0.31 MPa (internal bonding strength). The morphological images displayed the presence of lignocellulosic materials in the composite structures, whereas the FTIR study provides evidence of successful chemical interactions between the OPC and reinforcements. The results reveal a novel, eco-friendly and green composite panel fabrication technology that can facilitate panel manufacturers, especially in the construction and building sectors.

Combined Effect of Pressurized Water and Sustained Load on Self-Healing of Engineered Cementitious Composite Panels

Combined Effect of Pressurized Water and Sustained Load on Self-Healing of Engineered Cementitious Composite Panels

Experimental investigation of strengthening of masonry-infilled RC frames using prefabricated engineered cementitious composite panels

Cement-based composite materials such as engineered cementitious composites (ECCs) are appropriate for retrofitting buildings because of their high tensile strength and strain. This research evaluated the lateral behavior of strengthened masonry-infilled reinforced concrete (RC) frames reinforced with prefabricated engineered cementitious composite (PECC) panels. The goals of the proposed technique were to increase the energy absorption capacity and the lateral capacity of infilled RC frames and protect the stability of the masonry infills after cracking and brittle failure in the out-of-plane direction, which can contribute to the seismic vulnerability of a structure. The mechanical characteristics of the ECC materials, such as the tensile strength and strain and multiple cracks, were first determined. Then, nine diagonal compression tests were done on masonry panels strengthened with PECC panels. In these tests, two types of connection were compared and the best one was selected. Next, an existing one-story RC moment frame with one bay was scaled down for testing under lateral cyclic loading. The results indicated that the strength, deformation, stiffness, and energy absorption of the RC frames increased considerably. Additionally, the effects of the precast panel thickness, performance of the connections, and type of damage sustained were compared between the different types of tests. Overall, the PECC panels connected to the infill wall with the proposed connections improved the lateral behavior of the system in the in-plane direction and markedly mitigated the risk of collapse by confining the masonry infill wall.

Semi-dry technology-mediated coir fiber and Scots pine particle-reinforced sustainable cementitious composite panels

The demand for natural fiber-reinforced sustainable products is increasing continuously worldwide. The technology to produce lignocellulosic fiber-reinforced cementitious materials is currently limited; hence, new routes for composite development are being explored. The current study presents an innovative semi-dry technology implemented on lignocellulosic material (coir fiber and Scots pine particle) reinforced composite panels. Composite panels of 12 mm thickness and 1200 kg/m3 nominal densities were prepared from lignocellulosic materials and OPC (Ordinary Portland cement). Measurements determined the dimensions of the lignocellulosic materials to be the following: coir fibers were within 0.1 to 1.25 mm in length while Scots pine particles ranged from 0.355 to 1.6 mm in length. The lignocellulosic materials were loaded in different proportions (100% Scots pine, 60% Scots pine/40% coir, 50% Scots pine/50% coir, 40% Scots pine/60% coir, and 100% coir) to produce five composite panels. The proportions of water glass additive and OPC remained constant. A cheaper and more convenient novel fabrication approach (semi-dry technology) was utilized to produce the composite panels via pressing implementation (3.2 to 7.1 MPa). Finally, the thermal, physical, morphological, and mechanical properties of all the composite panels were tested. The experimental results were significant and could facilitate composite manufacturers with potential and sustainable products possessing superior performance characteristics. The most promising finding of this research is the increased thermal and mechanical properties of the composites along with significant dimensional stability against moisture with the increase in loading of coir fibers in the matrix system. The SEM (scanning electron microscopy) and SEM-mediated EDX (energy-dispersive X-ray spectroscopy) also provided the morphological and elemental analysis of the fibers, cements, and associated composites. The FTIR (Fourier transform infrared spectroscopy) study also further confirmed the successful reinforcement of the lignocellulosic materials and OPC. Moreover, the perceived thermal conductivity of the composite materials also indicates promising routes toward the development of insulation materials using renewable lignocellulosic materials.

Mechanical and durability performance of textile reinforced cementitious composite panels

Textile reinforced cementitious composites (TRCC) consist of technical textile and matrix material. A potential use of these new composite materials involves panels used as both a facade and strengthening material. As the use of these materials becomes widespread, the determination of their strength and durability properties becomes vital. In this study, textile reinforced cementitious composite panels were prepared by using a newly developed PPR (Pull pour roll) technique and machine. A polymer modified cementitious mortar was designed as matrix material and different textile materials were selected for the production of composite panels. Mineral admixtures, defoamer and superplasticizer materials were also used in the matrix mixture to obtain desired workability and mechanical properties. The influence of three different textile materials (Alkali Resistant Glass, Basalt and Polyvinylalcohol (PVA)) and the number of textile layers on the performance of composite panels were comparatively investigated. To simulate the outdoor environment composite panels will be exposed, wetting–drying curing regime was applied. Pull-off tests were carried out on composite panels before and after wetting–drying curing. In addition, diagonal compression tests were performed on infill walls strengthened with panels applied to one or double faces. Contribution of composite panels bonded to infill walls was investigated in terms of shear strength, shear modulus, ductility under shear and failure modes. Comprehensive experimental studies have shown that there is great potential for use of textile reinforced composite panels in the strengthening of infill walls.

Strengthening of reinforced concrete frames with engineered cementitious composite panels

Infill walls in reinforced concrete frames are susceptible to failure owing to their brittle nature. Their interaction with boundary columns during earthquakes may also cause shear damage in the columns. It is crucial to employ effective seismic strengthening strategies in order to mitigate the seismic risk induced by the infill walls. In this study, a new strengthening technique, conducted by bonding engineered cementitious composite (ECC) precast panels onto infill walls, was investigated. Three reinforced concrete frames, termed bare frame, infilled frame and strengthened frame, were tested by using the pseudo-dynamic testing method. The test specimens were three-storey, three-bay, half-scaled frames with the central bay having hollow clay brick infill walls. The specimens were subjected to three consecutive ground motions scaled to represent earthquakes with return periods of 144, 475 and 2475 years. The experimental results were compared to observe the influence of the infill walls on the reinforced concrete frames, and to demonstrate the performance of the proposed strengthening technique. It was found that application of ECC panels significantly increased the frame strength and stiffness while allowing the system to have a displacement ductility of about four.

Thermal insulation materials based on water hyacinth for application in sustainable buildings

The constant increase in environmental pollution and consumption of energy has prompted the construction industry to focus on thermal insulation. Non-renewable resources are commonly used for the production of thermal insulation materials. Therefore, a number of issues arise relating to the reuse or recycle of such materials. Also, a huge amount of energy is required for their production. Yet, another major issue of concern in India is the aquatic weed infestation in water bodies. Invasive weeds such as water hyacinth (WH) are posing severe environmental as well as economic issues. A potential remedy for these waste disposal and high dependence on non-renewable materials are the conversions of these aquatic weeds into sustainable construction material. The primary objective of this paper is to explore the utilization of WH petioles as a raw material resource for the production of thermal insulation material. The methodology to design the water hyacinth cement composite panel and its properties such as bulk density, water absorption, thermal conductivity, and flexural strength areincluded in this paper. The WH was collected; petioles were separated, sun-dried, milled into smaller particle sizes, and blend with a homogenous paste of cement and water. The homogenous mixture was poured into a mould and was compacted to produce the thermal insulation boards. The panel boards were made with water hyacinth particles that pass through 2.36 mm sieve. Water to water hyacinth ratio (w: WH) and the water hyacinth-cement ratio (WH: cement) used in the present work are 1.75 and 60: 40 respectively. In this paper, a comparative study between the thermal insulation materials made from WH with agro-waste based panel board and conventional thermal insulation materials are also included. This study indicates that WH biomass resources are a very good candidate for developing thermal insulation material and the correct combination of WH is absolutely comparable with conventional materials.

Uso potencial de la fibra de curauá (ananas acutifolius) para la fabricación de compuestos cementicios

This study aimed to characterize and evaluate the performance of the Amazonian plant fiber curaua (Ananas erectifolius) as reinforcement in the cementitious composite panels’ production process. For the production of these panels were determined extractives content and bulk density of the fibers. The panels were produced with curaua fibers, varying the contents (5%, 10% and 20%). Also, as a methodology, vegetable fibers were treated through immersion in cold water for 24 hours, immersion in hot water for 6 hours, and finally immersed in NaOH solution for 2 hours at a concentration of 1%. The panels were manufactured in the dimensions of 500x500x15 mm, a nominal bulk density of 1.60 g/cm 3 and kept under pressure (4 MPa) for 24 hours. After pressing the panels were conditioned for 28 days for cement cure. As a result, it was observed that the incorporation of 10% curaua fibers is possible as reinforcement in the cementitious matrix, in the manufacture of wood-concrete panels. It was also found that the chemical treatment of the fibers provided the improvement in the physical properties of the composites.

Axial compression behaviour of reinforced wallettes fabricated using wood-wool cement panel

Wood-wool cement composite panel (WWCP) is one of wood based composite material that produced in a stable panel form and suitable to be used as building wall system to replace non-ecofriendly material such as brick and other masonry element. Heavy construction material such as brick requires more manpower and consume a lot of time to build the wall panel. WWCP is a lightweight material with a density range from 300 kg/m3 to 500 kg/m3 and also capable to support an imposed load from the building. This study reported on the axial compression behaviour of prefabricated reinforced wallettes constructed with wood-wool cement panel. A total of six specimens were fabricated using two layers of cross laminated WWCP bonded with normal mortar paste (Portland cement) at a mix ratio of 1:3 (cement : sand). As part of lifting mechanism, the wallettes were equipped with three steel reinforcement (T12) that embedded inside the core of wallettes. Three replicates of wallettes specimens with dimension 600 mm width and 600 mm length were fabricated without surface plaster and with 16 mm thickness of surface plaster. The wallettes were tested under axial compression load after 28 days of fabrication until failure. The result indicated that, the application of surface plaster significantly increases the loading capacity about 35 % and different orientation of the panels improve the bonding strength of the wall.

Experimental Investigation on the Blast Resistance of Fiber-Reinforced Cementitious Composite Panels Subjected to Contact Explosions

This study investigates the blast resistance of fiber-reinforced cementitious composite (FRCC) panels, with fiber volume fractions of 2%, subjected to contact explosions using an emulsion explosive. A number of FRCC panels with five different fiber mixtures (i.e., micro polyvinyl alcohol fiber, micro polyethylene fiber, macro hooked-end steel fiber, micro polyvinyl alcohol fiber with macro hooked-end steel fiber, and micro polyethylene fiber with macro hooked-end steel fiber) were fabricated and tested. In addition, the blast resistance of plain panels (i.e., non-fiber-reinforced high strength concrete, and non-fiber-reinforced cementitious composites) were examined for comparison with those of the FRCC panels. The resistance of the panels to spall failure improved with the addition of micro synthetic fibers and/or macro hooked-end steel fibers as compared to those of the plain panels. The fracture energy of the FRCC panels was significantly higher than that of the plain panels, which reduced the local damage experienced by the FRCCs. The cracks on the back side of the micro synthetic fiber-reinforced panel due to contact explosions were greatly controlled compared to the macro hooked-end steel fiber-reinforced panel. However, the blast resistance of the macro hooked-end steel fiber-reinforced panel was improved by hybrid with micro synthetic fibers.

Response of Steel Fiber Reinforced Cementitious Composite Panels Subjected to Extreme Loading Conditions

Application of steel fiber reinforced cementitious composites (SFRCC) in the construction of protective structures against extreme loading conditions, such as high-velocity impact and blasts, is an active area of research. It is a challenging task to capture the material behavior under such harsh conditions where strain rate of loading exceeds beyond 104 s−1. In this paper, an effort is made to simulate numerically the multihits of short projectiles on SFRCC panels. A total of 90 numbers of SFRCC panels consist of various core layer materials, thicknesses, fiber volumes, and angle of obliquity, are tested under high-velocity impacts of short projectiles. In numerical simulations, the boundary conditions and impact loading sequence are maintained, similar to that used during impact tests. In order to carry out a realistic numerical simulation, in-service munitions and ammunitions are used. The numerical response is found to corroborate with experimental results. It is observed that, if two consecutive hits are made within a distance of ten times the diameter of the projectile, then it is considered a case of multihit, else, it is considered as single hit case. The damage contours based on effective plastic strain are found to correlate with impact-tested SFRCC panels.

Investigations on Steel Fibre Reinforced Cementitious Composite Panels under High Velocity Impact of Short Projectiles

Response of steel fibre reinforced cementitious composite (SFRCC) panels subjected to high velocity impact of short projectiles have great significance in designing protective structures. Numerical investigation carried out to determine the high velocity impact responses of SFRCC (300 mm square) panels is presented. In order to model the high velocity impact behaviour of SFRCC in the post peak region, the constitutive model of Riedel, Hiermaier and Thoma (RHT) is used with suitable modification in damage parameters. The numerical studies presented in this paper are validated using the experimental investigations carried out by the authors. The influences of steel fibrevolumes (0, 2, 4, 6, 8, and 10%) and thickness of panels (50, 60, 75, 100 mm), on depth of penetration (DOP) and crater dimensions is also investigated. Based on the numerical simulations, the important phenomenon like scabbing and perforation in the SFRCC panels are predicted for the chosen in-service ammunition (7.62 mm calibre) and munitions (AK - 47 rifle).

Comparative assessment of failure characteristics on fiber-reinforced cementitious composite panels under high-velocity impact

Abstract The effectiveness of fiber-reinforced cementitious composite (FRCC) panels with several blended short fibers for impact resistance was assessed. Impact tests were performed by striking the FRCC panels with a spherical steel projectile at high velocities. Impact tests were also performed on non-fiber reinforced cementitious composite (NCC) panels for comparison. The fibers helped control local damage in the FRCCs by bridging cracks in the panels. Critical failure by modes such as scabbing and perforation of the FRCC panels was suppressed, regardless of the fiber type, over the range of impact velocities under which the NCC panels were destroyed by perforation failure. Furthermore, the penetration path of the projectile was significantly observed in the cross-section of FRCC panels. This behavior is an obvious difference in the failure characteristic between FRCCs and NCC panels under high-velocity impact.

Fabrication and mechanical behaviors of cementitious composites reinforced by 3D woven lattice sandwich fabrics

Glass fibers were firstly woven to form three-dimensional (3D) woven lattice sandwich fabrics (WLSFs) which then were applied to reinforce cementitious foams and mortars to fabricate novel ductile cementitious composites. Failure behaviors of WLSF reinforced cementitious composite structures were studied through compression and three-point bending experiments. The WLSF greatly enhances the strength of cementitious foams at a level of four times. For cementitious mortars, compression strength of WLSF reinforced blocks is a little greater for the fraction of the textile is small as well as the compression strength of the textile pillars is not strong. But in flexure, excellent stretching ability of the glass fiber textiles greatly improves the flexural behavior of WLSF reinforced cementitious composite panels. Load capacity and ultimate deflection of these composite panels were greatly enhanced. Flexural capacity of the WLSF reinforced beam is four times greater. Reinforced by WLSF, failure of the cementitious composite is ductile.

Development of New Prefabricated Wall Constructed Using Wood-wool Cement Composite Panel

Sustainability in construction industry has brought new materials to be used as a wall element in building construction in Malaysia. Wood-wool cement composite panel (WWCP) is the wood based product which manufactured from renewable resources, less embodied carbon emission, lightweight, easy to process and fabricate and available to the construction industry to replace less eco-friendly materials such as common brick and other masonry element. In Malaysia, there are increasing interest in using WWCP as a wall element in building construction, however the structural performance under imposed load and the installation technique using this material still not well established. Therefore, this study aims to improve the sustainability in building construction with the development of new prefabricated wall constructed using wood-wool cement composite panel. Two types of fabrication techniques are considered in fabricating prefabricated wallettes with dimension of 1200mm x 1200mm (± 30mm). The wallettes type W1 is the current practiced technique, meanwhile wallettes type W2 is the new proposed fabrication technique. Three replicates of each type of wallettes were then tested under axial compression load in order to investigate their structural performance. The results of experimental testing showed that, the wallettes fabricated using the new fabrication technique significantly increased two times in load carrying capacity compared to wallettes with current practiced technique.

Numerical investigation on steel fibre reinforced cementitious composite panels subjected to high velocity impact loading

Abstract Steel fibre reinforced cementitious composite (SFRCC) panels are numerically investigated for their performances under high velocity impact of short projectiles. Numerical responses are obtained using advanced constitutive material model of Riedel–Hiermaier–Thoma (RHT) for cementitious materials and adopting appropriate modelling techniques. Effects of steel fibre volume and the thickness of panels on the impact performance are mainly highlighted in this paper. Various characteristics phenomenon during impact on cementitious composite panels namely, spalling, cracking, scabbing and perforation, are captured which is a difficult task. Scabbing is likely to occur when tensile stresses at the back face of the panel exceed dynamic tensile strength of the material. Various critical aspects in numerical modelling like boundary conditions, material input parameters, and handling severe distortion of the Lagrangian based finite elements are appropriately explained. Design chart is also developed to determine optimum fibre volume and thickness for an impact energy level up to 2.2 kJ. The numerically predicted impact responses are found to corroborate well with experimental results.

Axial Compression Behaviour of Wallettes Constructed Using Wood-Wool Cement Composite Panel

This paper reports on the investigation of the structural behavior of wallettes made from wood-wool cement composite panel (WWCP). Initially, a series of experimental test were carried out to investigate the mechanical properties of WWCP namely density, bending properties (MOR and MOE), compressive strength and tensile strength for two thicknesses of WWCP (50 mm and 100 mm). Then, the axial compression capacity of WWCP was investigated using wallettes. In the fabrication of wallettes, there are two types of panel arrangement considered and denoted as W1 and W2. For W1, 100 mm thick WWCP was used and cut into size of 300 mm width and 600 mm length. The cut panels were then stacked vertically (two layer) in running bond pattern to form a 600 mm x 600 mm wallettes. The top and bottom panels were connected together with 10 mm thick mortar paste and three vertical steel bars were inserted between panels. In addition to this, an enhancement has been made by fixed two U-Nail at the connection area on each side of wallettes. For W2, a new panel arrangement technique has been proposed by integrating two layers of 50 mm thickness of WWCP (cut into size of 300 mm width and 600 mm length) with different orientation of panel arrangement to form a 600 mm x 600 mm wallettes. The front side of the panels has been arranged in the longitudinal direction, whereas back side in transverse direction. The front and back side panels were bonded together using either adhesive or mortar mix with different thicknesses to form approximately 100 mm (± 15 mm) thick wall. For mechanical properties of WWCP, it was found that, the strength properties of the panel decreases with the increased in panel thickness. For the axial compression test of wallettes, the results showed that, a new proposed of panel arrangement technique with mortar mix significantly improved the stability as well as increased load carrying capacity of wallettes.

Response Simulation of a Micro Reinforced Concrete Target Under Ballistic Impact

The response of concrete structures subjected to impact loading has received extensive attention in both civil and military applications. Research on improving the shock resistance of concrete has led to the development of cementitious composites. Micro Reinforced Concrete (MRC), a type of cementitious composite, is a concrete matrix embedded with multilayered steel wire meshes. This paper presents 3D hydrocode simulations of MRC panels subjected to impact under a ballistic range. A finite element model based on Lagrange formulation is used to represent both a 300 mm × 300 mm × 100 mm target with 30 layers of wire mesh and a 5.56 × 45 mm projectile in simulations. Penetration depth and damage patterns of the MRC mesh cement composite panel are numerically compared with those of the field experiment. The results show a relatively good agreement.