Structural Performance of Ferrocement Beams Incorporating Longitudinal Hole Filled with Lightweight Concrete (original) (raw)
Related papers
Construction and Building Materials, 2018
The main objective is to studying the flexural behaviour of ferrocement beams with lightweight cores and types of mesh reinforcement. Cores were made of autoclaved aerated lightweight brick, extruded foam, and lightweight concrete cores; and are reinforced with expanded metal mesh, welded wire mesh and fibre glass mesh. Flexural behaviour including first crack loads and deflections, ultimate loads and deflections, ductility index, strain characteristics, crack pattern and failure mode were investigated. Effect of different types of core materials and mesh reinforcement on the flexural behaviour of studied beams was investigated. Ferrocement beams of light weight cores may be promising as an alternative to conventional beams especially for low cost residential buildings. a b s t r a c t Sixteen reinforced concrete beams having the cross-sectional dimensions of 100 Â 200 Â 2000 mm and clear span of 1800 mm were cast and tested until failure under a single mid-span concentrated load. Ferrocement beams in this research contained either an Autoclaved Aerated lightweight brick Core (AAC), Extruded Foam Core (EFC), or a Lightweight Concrete Core (LWC); and were reinforced with either Expanded Metal Mesh (EMM), Welded Wire Mesh (WWM) or Fibre Glass Mesh (FGM). Structural behaviour of studied beams, including first crack, ultimate load, deflection, ductility index, strain characteristics , crack pattern and failure mode were investigated. Experimental work results showed that ferrocement beams exhibited higher ductility indices than those of the control normal and lightweight test beams to different degrees. Ferrocement beams made of EFC core generally gave the lowest ductility index while the highest ductility index was found for beams made of AAC and LWC cores. Ferrocement beams demonstrated better crack control and did not undergo spalling as opposed to the conventional beams. Specimens reinforced by EMM showed better ductility than those reinforced by WWM and even after increasing the reinforcement ratio of WWM, the situation did not change. Specimens reinforced by FGM had the lowest ductility compared to specimens reinforced by steel mesh. Cracks were found to develop more rapidly in beams reinforced by EMM, while beams reinforced by FGM exhibited the least amount of cracks. The results of this research showed that ferrocement beams of light weight cores may be promising as an alternative to conventional beams and may be viable alternatives especially for low cost residential buildings.
The main objective is to studying the flexural behaviour of ferrocement beams with lightweight cores and types of mesh reinforcement. Cores were made of autoclaved aerated lightweight brick, extruded foam, and lightweight concrete cores; and are reinforced with expanded metal mesh, welded wire mesh and fibre glass mesh. Flexural behaviour including first crack loads and deflections, ultimate loads and deflections, ductility index, strain characteristics, crack pattern and failure mode were investigated. Effect of different types of core materials and mesh reinforcement on the flexural behaviour of studied beams was investigated. Ferrocement beams of light weight cores may be promising as an alternative to conventional beams especially for low cost residential buildings.
Experimental and FE simulations of ferrocement columnsincorporating composite materials
Structural Engineering and Mechanics, 2017
In this study, 10 ferroconcrete concrete (FC) beams with lightweight cores reinforced with welded steel mesh as a shear reinforcement were evaluated under three-point bending tests along with two conventionally normal-weight concrete (NWC) beams. Expanded polystyrene and lightweight aerated autoclaved brick wastes were used to create lightweight core concrete. The main factors include the type of lightweight concrete used for the core, beam concrete type, the form and number of holes, the existing steel mesh fabric, the hollow, and the hole placement. This study was done on the tested beams' ductility index, failure modes, first cracking loads and associated deflections, and ultimate loads besides corresponding deflections. Experimental results showed that the use of FC, various filling materials, and welded steel meshes in place of traditional stirrups enhanced the ultimate load by 36.6-107.3%, the ultimate deflection by 6-272%, and the ductility by 89-1155% when referenced to a control NWC beam. When the holing ratio increased from 10 to 20%, the ductility of FC beams was enhanced by 307.7%. Proposed equations were developed to predict the ultimate load and bending moment capacity of FC beams while taking into account the compressive strength of the beam body and filling material, the holing ratio, the tensile reinforcement ratio, and the volume fraction of the steel mesh. Highlights • This study is focusing on structural performance of ferrocement beams with lightweight cores reinforced with steel mesh fabric as a shear reinforcement. • Lightweight core concrete with steel mesh fabric reinforcement was made either using lightweight aerated autoclaved brick aggregate (LAABA) or expanded polystyrene (EP). • Impact of core lightweight concrete type, shape/number of holes, existing steel mesh fabric, concrete type, existing hollow core, positioning of hole on structural performance of the beams were performed. • Structural performance factors such ductility index, failure mechanism, first cracking loads and deflections and ultimate loads and deflections were studied.
International Journal of Concrete Structures and Materials, 2014
This paper presents the results of an investigation aimed at developing reinforced concrete beams consisting of precast permanent U-shaped reinforced mortar forms filled with different types of core materials to be used as a viable alternative to the conventional reinforced concrete beam. To accomplish this objective, an experimental program was conducted and theoretical model was adopted. The experimental program comprised casting and testing of thirty beams of total dimensions 300 9 150 9 2,000 mm consisting of permanent precast U-shaped reinforced mortar forms of thickness 25 mm filled with the core material. Three additional typical reinforced concrete beams of the same total dimensions were also cast to serve as control specimens. Two types of single-layer and double-layers steel meshes were used to reinforce the permanent U-shaped forms; namely welded wire mesh and X8 expanded steel mesh. Three types of core materials were investigated: conventional concrete, autoclaved aerated lightweight concrete brick, and recycled concrete. Two types of shear connections between the precast permanent reinforced mortar form and the core material were investigated namely; adhesive bonding layer between the two surfaces, and mechanical shear connectors. The test specimens were tested as simple beams under three-point loadings on a span of 1,800 mm. The behavior of the beams incorporating the permanent forms was compared to that of the control beams. The experimental results showed that better crack resistance, high serviceability and ultimate loads, and good energy absorption could be achieved by using the proposed beams which verifies the validity of using the proposed system. The theoretical results compared well with the experimental ones.
Behavior of Composite Ferrocement Reinforced Concrete Beams
Journal of Advanced Sciences and Engineering Technologies, 2021
The Ferrocement is a type of thin reinforcement concrete made of cement- sand mortar mixture with closely spaced of relatively small diameter wire meshes with or without bars of small diameter called skeletal bar. The purpose of the current study is to identify the behavior of the composite fibrocement and reinforced concrete beams. The main variables of the current study are the number of layers of wire mesh, the casting time for the second layer ( Normal concrete) , and the effect of the presence or absence of the skeletal bars. The current study included the casting of two reference beams with a different reinforcing ratio (2φ8 mm), and (3φ8 mm). The study also included the casting of eight composite beams of fibrocement and reinforced concrete. The results show that the use of fibrocement layer, with (4,6,8) layers of wire meshes, skeletal bar, and the first casting period (1.5 hr) leads to increase the ultimate load by (17.142%, 21.42%,and 22.85%) also the cracking load increas...
Flexural behaviour and theoretical prediction of lightweight ferrocement composite beams
Case Studies in Construction Materials
Sixteen full-scale simply supported composite beams of the same dimensions, breadth=100 mm, thickness, 200 mm, and length of 2000 mm, subjected to flexural loading, were experimentally tested and their structural parameters, namely, pre-crack stiffness, serviceability loads, post-cracking loads, energy absorption, ultimate load-to weight ratio, and compressive strains were investigated. In addition, theoretical prediction of ultimate loads was carried out to adopt a theoretical approach as a design methodology for ferrocement elements. Experimental results showed that pre-crack stiffness, maximum service loads, maximum values of energy absorption and ultimate loads to weight ratios of ferrocement beams are higher than that of lightweight control beam by up to 46%, 32%, 64.4% and 32.8%, respectively. Higher postcracking loads were exhibited by beams reinforced by expanded metal mesh, compared to those reinforced by welded wire mesh regardless of the core filling type. For post cracking load indicator, confinement with expanded metal mesh was the decisive factor affecting the postcracking load capacity. Beams reinforced with expanded metal mesh showed higher energy absorption than those of the other beams reinforced with welded wire mesh or fiberglass mesh. Increasing the amount of mesh reinforcement results in higher energy absorption for beams made of Autoclaved Aerated Lightweight Brick Core (AAC). Generally, the maximum compressive strains of the ferrocement composite beams were generated at higher loads compared to those of the control beams. Theoretical calculations, based on the assumption of strains and forces distribution block, results in acceptable prediction of the ultimate loads. The ratio of experimental to theoretical ultimate loads ranges from 0.91 to 1.26. This study showed that ferrocement composite beams may be used as an alternative to traditional reinforced normal or lightweight concrete beams after careful choice of the combination of core and mesh types to suit the application in question.
Ferrocement, also referred to as ferro concrete or reinforced concrete, a mixture of Portland cement and sand applied over layers of woven or expanded steel mesh and closely spaced small-diameter steel rods rebar. Retrofitting techniques are used in field and out of all plate bonding technique is considered as the best. In this technique, the plates of different materials are bonded to the surface of structural member to increase its strength. Ferrocement sheets are most commonly used as retrofitting material these days due to their easy availability, economy, durability, and their property of being cast to any shape without needing significant formwork. In the present work, effect of wire mesh orientation on the strength of stressed beams retrofitted with Ferrocement jackets has been studied. The beams are stressed up to 75 percent of safe load and then retrofitted with Ferrocement jackets with wire mesh at different orientations. The results show that the percent increase in load ...
Impact Resistance of Reinforced Concrete Beams Encased By Ferro cement
2018
Strengthening reinforced concrete beams by a thin layer of ferrocement gives favourable properties such as smaller crack spacing and width, greater toughness which increases their impact load capacity, excellent bond in contact surface, and superfluity of formwork. The purpose of the experimental program in the present work is to show the effect of combination of conventional reinforced concrete beam encased by a thin layer of ferrocement. In this work, the first part of the experimental program covers the effect of some variables that affect the application of ferrocement in strengthening of reinforced concrete beams that are subjected to impact loads. The effect of number of layers of wire mesh, thickness of ferrocement, shape of encasement, amount, fastening and distribution of skeletal steel, mortar strength and nature of bond between concrete and ferrocement are considered. In addition, two reinforced concrete beams were constructed with low compressive strength to investigate ...
Structural Behavior of Ferrocement Concrete Plates Subjected to Flexural and Dynamic Loadings
Journal of Engineering Research and Reports, 2021
Ferrocement is one of the structural materials, widely used due to its advantages from its particular behavior such as mechanical properties, and impact strength. This paper deals with the impact studies and energy absorption properties of ferrocement slabs. For these studies, 11 different ferrocement slabs of size 50 mm X 500 mm X 25 mm were cast with alteration in the combinations of mesh layers and test results are analyzed to find the different crack patterns .The test specimens were loaded by 3.10 kg under its height 1.20 m in the center of plates. The ferrocement plates were divided into 4 groups reinforced with steel mesh, steel mesh with steel bars, percentage of rubber and fiber. The impact energy at initial cracking stage and at failure was determined for all the slabs. Results of reinforced ferrocement plates emphasized that increasing the number of the steel mesh layers in the ferrocement forms increases the first cracking load, ultimate load and energy absorption. Using steel bars with steel meshes led to higher energy absorption than that obtained when using mild steel bars only. Using rubber and fiber achieved high impact energy.
Shear behavior of light weight ferrocement concrete slabs
ERJ. Engineering Research Journal
The objective of the work presented in this research was to develop light weight composite slab subjected to punching load by using column slab connection at the center of the slab which comprises polystyrene block of thickness 80 mm reinforced with welded galvanized steel mesh or expanded steel mesh. The use of expanded metal mesh and welded steel mesh was proposed as a viable alternative to ordinary steel bars in reinforcing ferrocement plates, also it was proposed to use it with ordinary steel bars to enhance the mechanical behavior of the composite slab. For light weight sandwich elements, light weight polystyrene of density 12Kg/m3 is used as a core material and welded wire meshes or expanded steel meshes are to be used as steel reinforcement at the two thin skin layers. Twelve squares composite light weight slabs were developed having the dimensions of 1200mm x 1200mm and overall thickness of 140mm were tested simply supported along all four sides under central column slab connection until failure. This research presents the behavior of ferrocement lightweight slabs under punching shear. The effects of various types of reinforcing materials were investigated. Using such lightweight materials will contribute to decreasing the weight of the elements and consequently decreasing the overall dead load of the building. Moreover, the study aimed at improving some other characteristics like flexural strength,