Comparative Study Between Flowable High Strength Mortar and Flowing High Strength Concrete

This paper presents the results of an investigation aimed to evaluate the comparison between high strength flowing concrete (HSFC) and high strength flowable mortar (HSFM) from the view of density, compressive strength and flexural strength at the age of 7 and 28 days. The results illustrate that the use of Silica fume (10 % as a partial replacement of cement) and superplasticizer (1.6- 2.2% of cementitious materials) gives the properties of high flowability with the high strength for each of concrete and mortar mixes. Besides, the compressive strength and flexural strength for each of mortar and concrete have been enhanced by the inclusion of silica fume

The Development Of Fibres Reinforced Flowable High Strength Mortar And Concrete As Repair Materials (Abstract)

Kajian tentang konkrit kekuatan tinggi mudah alir dan mortar sebagai bahan pembaikan telah dijalankan untuk memahami tabiat bahan-bahan ini di kawasan-kawasan pembinaan. The study of Flowable high strength concrete and mortar as repair materials was carried out to understand the behaviour of these materials on construction sites

Production of durable high strength flowable mortar reinforced with hybrid fibers

This study deals with the production of durable high strength flowable mortar (HSFM). Firstly, the optimum percentage of silica fume was determined due to Pozzolanic Activity Index (P.A.I) test. Secondly, the selected mortar reinforced by different percentages of steel fibers or hybrid fibers of  steel fibers , palm fibers and synthetic fibers (Barchip) to prepare HSFM mixes. Such mixes were tested in compressive strength, splitting tensile strength, static modulus of elasticity, flexural strength, toughness indices determination, and impact load for all the mixes. Lastly, the effects of seawater exposure on the properties of HSFM have been observed. The results show that the use of 10% silica fume as a partial replacement of cement indicate the best P.A.I. On the other hand, the hybridizations of such fibers enhance the performance of HSFM mixes. In addition, the hybrid fibers reduce the permeability of HSFM leading to significance improvement against seawater exposure

Effectiveness of high performance mortar reinforced with fibers as a repair material

The present work deals with engineering properties of high performance mortar (HPM) to be used as a repair material. The experimental study was conducted on HPM reinforced with mono steel fibers and hybrid fibers consist of steel and polypropylene fibers. The economical efficiency of the designed mono and hybrid fibers reinforced mortar were presented. The results indicate that the hybridization of 1.8% steel fibers and 0.2% polypropylene fibers is very beneficial to decrease the production cost of fiber reinforced mortar for large scale construction project applications. The combined system of substrate concrete with different mixes of HPM was used to study its bond strength properties. The experimental tests are: two-part bond strength tests in additional to three part-bond strength tests. It was found that HPM reinforced by hybrid fibers has the best performance when two-part bond strength is required. On the other hand, in three parts bonding, the combined system of NC with epoxy has the best bond strength while HPM reinforced fibers show a better failure mode

The Influence of Hybrid Fibers and Nanomaterials (Nano Glass with Nano Slag) on the Behavior of Reactive Powder Concrete

The new production for reactive powder concrete (RPC) has become an interesting topic due to the dramatic properties that such materials can give. Thus, this study has been prepared to observe the properties of RPC mixes reinforced with micro steel fibers (MSF) by the order of 2% volumetric fractions (vol.). As well, hybrid fibers from MSF, sisal fiber (SIF), and also human hair fibers (HHF) have been included in the RPC mix in the order of 1.5% MSF plus 0.5% SIF, 1.5% MSF plus 0.5% HHF, and 1.5% MSF plus 0.25% SIF plus 0.25% HHF, respectively. Besides, the inclusion of two different nanomaterials combination by 2.5% from Nano glass powder (NG) and 2.5% Nano Iron slag powder(NS) was performed into that reinforced RPC. The preparation of these different RPC mixes was followed by testing them to investigate the performance of such RPC based on the properties of flowability, compressive strength, tensile strength, flexural strength, flexural toughness, and static modulus of elasticity. The results showed that the incorporation of 2%MSF increases the compressive strength, tensile strength, and flexural strength by 6.76%, 12.45%, and 14.34%, respectively, at 90 days. Whereas, the reinforcing of RPC by 1.5% micro steel fibers(MSF) with 0.25% sisal fibers (SIF) and 0.25% human hair fibers(HHF) rises the values of compressive strength, tensile strength, and flexural strength by 5.38%, 11.59%, and 14.05%, respectively, at age of 90 days. Moreover, the uses of nanoparticles as 2.5%NG with 2.5%NS in addition to 2%MSF increase the compressive strength, tensile strength, and flexural strength by 33.09%, 36.05%, and 43.68% at age of 90 days, respectively. The use of 1.5% MSF  plus 0.25% SIF plus 0.25% HHF with the mentioned nanoparticles(2.5%NG and 2.5% NS) boosts the best performance by converting such concrete from brittle material to ductile material. &nbsp

Production of High Performance Mortar Containing Metakaoline and Silica Fume

The utilization of Pozzolanic materials is fundamental in producing low cost construction materials for utilization in growing nations. This paper elaborates on the effect of Silica fume (SF) and Metakaolin (MK) mixture as a partial replacement of cement in mortar. The using of the high range water reducer (superplasticizer) gives higher quality than plane mixes. (SF) is a ‘‘very fine noncrystalline silica produced in electric arc furnaces as a by-product of production of elemental silicon or alloys containing silicon’’. The fundamental physical effect of (SF) in concrete is that of filler, because of its fineness can fill the voids between (OPC) particles in the same way that fine aggregate fills the voids between coarse aggregates. This research shows the result of an experimental program carried out to find the suitability of (SF) and (MK) combination to produce High Performance Mortar (HPM). The optimal doses of (SF) and (MK) in combination were found to be 9% and 11% (by weight) respectively, when used as partial replacement of (OPC). 

Quaternary Blended Cement Mortars Containing Wood Ash, Glass and Slag Powders

A quaternary supplementary cementitious materials as partial replacement of ordinary Portland cement decreases CO2 emission. This paper has investigated the properties of mortars made from different quaternary blends of wood ash, steel slag powder and glass powder with ordinary Portland cement at different replacement levels of 0, 24, 25, and 30% by weight of the binder. The blended mortar mixtures tested for flow, compressive strength and density. The results showed that the flow of mortars is decreased with the combined use of steel slag powder, glass powder, and wood ash compared with control mix. Compressive strength reduced with the combination of steel slag powder, glass powder and wood ash but this reduction effects is acceptable especially at 24% replacement contain super-plasticizer compared with the ecological benefit

Proportioning of Lightweight Concrete by the Inclusions of Expanded Polystyrene Beads (EPS) and Foam Agent

This paper illustrates the performance of lightweight concrete using various amounts of expanded polystyrene beads (EPS) and different amounts of foam agent to produce lightweight concrete. The objective of this paper is to produce lightweight concrete with good workability and strength, by different mix proportion of foam agent (0.4, 0.6, 0.8, 1, 1.2 kg/m3) and varying water cement ratio (w/c) depending on the flow. Besides, various proportions using different percentages of EPS in order of volume fractions are used. The flow range used in the study is 110-130%. Each mix proportion is tested for compressive strength, modulus of rupture, density and voids ratio. The results gives acceptable ranges of strength for lightweight concrete produced by the inclusions of EPS beads and foam concrete. Therefore, the lightweight concrete produced in this work can be used for structural applications like multistory building frames, floors, bridges and prestressed or precast elements. </p

The stability of gabion walls for earth retaining structures

The stability of earth retaining structures in flood prone areas has become a serious problem in many countries. The two most basic causes of failure arising from flooding are scouring and erosion of the foundation of the superstructure. Hence, a number of structures like bridges employ scour-arresting devices, e.g., gabions to acting on the piers and abutments during flooding. Research was therefore undertaken to improve gabion resistance against lateral movement by means of an interlocking configuration instead of the conventional stack-and-pair system. This involved simulating lateral thrusts against two dimensionally identical retaining wall systems configured according to the rectangular and hexagonal gabion type. The evolution of deformation observed suggested that the interlocking design exhibits better structural integrity than the conventional box gabion-based wall in resisting lateral movement and therefore warrants consideration for use as an appropriate scour-arresting device for earth retaining structures

Production of geoploymer mortar reinforced with sustainable fibers

Geopolymer has been presented as new evolution in the concrete technology world, where cementitious materials such as ceramic powder and Slag have been replaced by high percentages of cement used in construction. Thus, the activation of such materials was performed by highly alkaline solutions in order to be acted as a binder in the mix. Therefore, the selection of suitable ingredients proportion of geopolymer mortar to achieve desired strength at required workability has been intended in this study. The experimental Program has been implemented for the preparation of geopolymer mortar mixes. The concentration of sodium hydroxide solution was kept constant in the order of 12 M throughout the experiment. The ratio of Water to geopolymer binder ratio was 0.35, alkaline solution-to- cementitiuos materials ratio was 0.30 and sodium silicate-to-sodium hydroxide ratio was 1.85 by mass. Workability of geopolymer mortar was measured by flow table apparatus and cubes of 50 mm side were cast and tested for compressive strength after 28 days of normal water curing. The study concludes that the combination of ceramic powder and Slag up to 40% (by weight), in the total binder material, can be used for developing the geopolymer mortar. Continuously, the use of 1% steel fibers or 1% steel fiber with 0.5% sisal fibers promotes the level of cement replacement by such cementitous materials (slag and ceramic powder) up to 60%