Properties and durability of concrete with olive waste ash as a partial cement replacement

Tayeh, Bassam A.,Hadzima-Nyarko, Marijana,Zeyad, Abdullah M.,Al-Harazin, Samer Z. Techno-Press 2021 Advances in concrete construction Vol.11 No.1

This research aims to study the utilization of olive waste ash (OWA) in the production of concrete as a partial substitute for cement. Effects of using OWA on the physical and mechanical properties of concrete mixtures have been investigated. This is done by carrying out tests involving the addition of various percentages of OWA to cement (0%, 5%, 10% and 15%). For each percentage, tests were performed on both fresh and hardened concrete; these included slump test, unit weight test and compressive strength test after 7, 28 and 90 days. Durability tests were investigated in solutions containing 5% NaOH and MgSO4 by weight of water. In addition, resistance to high temperatures was tested by subjecting the cubes to high temperatures of up to 170℃. The results of this research indicate that a higher percentage of OWA gives a lower compressive strength and lower workability but higher performance in terms of durability against both different weather conditions and high temperatures.

Influence of substrate roughness and bonding agents on the bond strength between old and new concrete

Magbool, Hassan M.,Tayeh, Bassam A. Techno-Press 2021 Advances in concrete construction Vol.12 No.1

This research aims to study factors affecting the strength of adhesion between old concrete and new concrete. Among the factors that have been studied in this research are the type of bonding material and the roughness of the surface adhesion, four types of bonding materials (EPICHOR-1768, C-Latex, SikaBond-T21, EPICHOR-500) have been selected because they are available in local markets. A wire brush is used in order to increase the roughness of sample surfaces. The pull-off and slant shear tests have been adopted to assess the bonding strength between the test the old and new concrete. 30 cylindrical samples (7 cm diameter) have been examined by pull-off test, also slant shear test was conducted on 40 samples (10 cm×10 cm×30 cm). The obtained results showed that there is an active role for the bonding material as well as the surface roughness to increase the strength of adhesion between the old and new concrete. Also, it showed that the best of these bonding materials is EPICHOR-1768 because of its significant impact in increasing the strength of the adhesion between the old and new concrete where the percentage of increase 124% in the pull-off test and 48% in slant shear test, compared to the reference sample for each test. As well, as a result of roughening the surface by brush, the strength of adhesion reaches 4% increase in the pull-off test and 23% in the slant shear test compared with the reference sample for each test, which demonstrates the importance of surface roughness to increase the bonding strength between the old and new concrete.

Combined effect of lightweight fine aggregate and micro rubber ash on the properties of cement mortar

Ibrahim, Omar Mohamed Omar,Tayeh, Bassam A. Techno-Press 2020 Advances in concrete construction Vol.10 No.6

Exterior walls in buildings are exposed to various forms of thermal loads, which depend on the positions of walls. Therefore, one of the efficient methods for improving the energy competence of buildings is improving the thermal properties of insulation plaster mortar. In this study, lightweight fine aggregate (LWFA) and micro rubber ash (MRA) from recycled tires were used as partial replacements for sand. The flow ability, unit weight, compressive strength, tensile strength, thermal conductivity (K-value), drying shrinkage and microstructure scan of lightweight rubberized mortar (LWRM) were investigated. Ten mixtures of LWRM were prepared as follows: traditional cement mortar (control mixture); three mixes with different percentages of LWFA (25%, 50% and 75%); three mixes with different percentages of MRA (2.5%, 5% and 7.5%); and three mixes consisting both types with determined ratios (25% LWFA+5% MRA, 50% LWFA+5% MRA and 75% LWFA+5% MRA). The flow ability of the mortars was 22±2 cm, and LWRM contained LWFA and MRA. The compressive and tensile strength decreased by approximately 64% and 57%, respectively, when 75% LWFA was used compared with those when the control mix was used. The compressive and tensile strength decreased when 5% MRA was used. By contrast, mixes with determined ratios of LWFA and MRA affected reduced unit weight, K-value and dry shrinkage.

Effectiveness of bond strength between normal concrete as substrate and latex-modified sand concrete reinforced with sisal fibers as a repair material

Oday Z. Jaradat,Karima Gadri,Bassam A. Tayeh,Ahmed M. Maglad,Abdelhamid Guettala Techno-Press 2023 Advances in concrete construction Vol.15 No.6

This study investigated the use of latex-modified sand concrete reinforced with sisal fibers (LMSC) as a repair material. Notably, no prior research has explored the application of LMSC for this purpose. This paper examines the interface bond strength and the type of failure between LMSC as a repair material and the normal concrete (NC) substrate utilising four different surfaces: without surface preparation as a reference (SR), hand hammer (HA), sandblasted (SB), and grooved (GR). The bond strength was measured by bi-surface shear, splitting tensile, and pull-off strength tests at 7, 28, and 90 days. Scanning electron microscopy analysis was also performed to study the microstructure of the interface between the normal concrete substrate and the latex-modified sand concrete reinforced with sisal fibers. The results of this study indicate that LMSC has bonding strength with NC, especially for HR and SB surfaces with high roughness. Therefore, substrate NC surface roughness is essential in increasing the bonding strength and adhesion. Eventually, The LMSC has the potential to repair and rehabilitate concrete structures.

Credit Impact on Firm Profitability in Iraqi, Jordanian, and Kuwaiti Stock Markets

MAHDI, Dalal Salih,AL-NAIMI, Adnan Tayeh Korea Distribution Science Association 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.3

In this paper, the relationship between the profitability level of an enterprise and the credit policy adopted by an enterprise was measured. A sample of industrial firms listed on the stock exchanges of Iraq, Jordan, and Kuwait was analyzed. Five industrial firms were randomly selected from each exchange with a condition of having at least 5 year-activity. The total sample size was 15 industrial firms. The study financial data was imported from the sample firms' websites. The financial data was for the financial year 2017. The Regression Analysis was adopted to measure the impact of trade credit on the profitability of an enterprise using the SPSS software. It was found that the receivable accounts have a proportional relationship with the turnover property rights rate. Similarly, the statistical results showed that the turnover property rights rate increased with an increase in the turnover receivable accounts rate and the percentage of investment in receivable accounts. The influence of trade credit on the enterprise profitability percentage in the Iraq stock exchange, Amman stock exchange, and Boursa Kuwait were 0.938, 0.200, and 0.089, respectively. The results showed that the three secondary assumptions were incorrect, while the zeroth assumption, i.e., trade credit has no influence on profitability, was correct.

Novel approach to improve nano green mortar behaviour using nano-paper waste with nano-metakaolin

Radwa Defalla Abdel, Hafez,Bassam A., Tayeh,Raghda Osama Abd-Al, Ftah,Khaled, Abdelsamie Techno-Press 2022 Advances in concrete construction Vol.14 No.5

Treatment of solid waste building materials is a crucial method of disposal and an area of ongoing research. New standards for the treatment of solid waste building materials are necessary due to multisource features, huge quantities, and complicated compositions of solid waste. In this research, sustainable nanomaterial mixtures containing nano-paper waste (NPW) and nano-metakaolin (NMK) were used as a substitute for Portland cement. Portland cement was replaced with different ratios of NPW and NMK (0%, 4%, 8%, and 12% by weight of cement) while the cement-to-water ratio remained constant at 0.4 in all mortar mixtures. The fresh properties had a positive effect on them, and with the increase in the percentage of replacement, the fresh properties decreased. The results of compressive strength at 7 and 28 days and flexural strength at 28 days show that the nanomaterials improved the strength, but the results of NMK were better than those of NPW. The best replacement rate was 8%, followed by 4%, and finally 12% for both materials. The combination of NMK and NPW as a replacement (12% NMK + 12% NPW) showed less shrinkage than the others because of the high pozzolanic reactivity of the nanomaterials. The combination of NMK and NPW improved the microstructure by increasing the hydration volume and lowering the water in the cement matrix, as clearly observed in the C-S-H decomposition.

Role of expanded clay aggregate, metakaolin and silica fume on the of modified lightweight concrete properties

Tawfik Taher A.,AlSaffar Doha M.,Tayeh Bassam A.,Metwally Khaled Ali,ElKattan Ibrahim M. 한국자원공학회 2021 Geosystem engineering Vol.24 No.3

This investigation aimed to assess the effect of micro-cementitious materials on the mechanical properties and sulphate resistance of modified eco-efficient lightweight concrete (MDLWC). A modified lightweight concrete (MDLWC) was produced by mixing Light-expanded clay aggregate (LECA) with normal coarse aggregate (dolomite cushed rock). The impact of using different percentage of micro-cementitious materials which was micro silica fume (5–20%) and metakaolin(10–35%) on the mechanical properties (compressive strength, splitting tensile and flexural strength), waves transmission velocity of the ultrasonic pulses and sulphate resistivity of MDLWC was studied. The overall results illustrated that the use of micro-cementitious materials in MDLWC caused an enhancement on MDLWC properties. However, the MDLWC specimens containing micro silica fume showed better results than metakaolin. The best results were observed while using samples containing 10% micro silica fume and 30 % metakaolin individually or combined. In addition, the usage of combined mixture of 10% micro silica fume and 30% metakaolin MDLWC mix showed the best improvement rate in compressive, splitting tensile and flexural strengths by 25, 53.3 and 66.6%, respectively, compared to control MDLWC specimens. On the other hand, the direct empirical equations were proposed on the basis of strong and nonlinear regression analysis using the test data to predict the mechanical properties of MDLWC relationships, rationally. Experimental tests were conducted on ultrasonic pulses velocity, which showed good correlation equation strength of MDLWC. Scanning electron microscopy illustrated that the pores of concrete is smaller for SF and MK individually or combined with MDLWC compared to the control concrete, demonstrating an enhancement within the interfacial microstructure with the pozzolanas incorporation. The previous difference could be explained due to the concrete strength and sulphate penetrability to an extent.

Effect of high temperatures on mechanical, radiation attenuation and microstructure properties of heavyweight geopolymer concrete

Mohamed Amin,Abdullah M. Zeyad,Bassam A. Tayeh,Ibrahim Saad Agwa 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.80 No.2

Heavyweight geopolymer concrete (HWGC) is a new concrete type that combines the benefits of geopolymer concrete (GC) and heavyweight concrete. HWGC can be used to produce particular properties such as high radiation shielding, and mass concrete elements. HWGC based on fly ash and ground granulated blast furnace slag, using electric arc furnace steel slag (EAFSS), barite and ilmenite coarse aggregates can substantially have higher specific gravities than concrete made with crushed dolomite. In the experimental work carried out on four main groups, 13 GC mixes are prepared by using heavyweight coarse aggregates (HWCAs) at volume ratios of 0%, 25%, 50%, 75% and 100%. Fresh and mechanical properties, compressive and tensile strengths, and influence of high temperature on radiation are investigated for specimens subjected to high temperatures of up to 900°C for 1, 2 and 3 hours. Moreover, the internal structure of geopolymer is analyzed using scanning electron microscope and energy-dispersive X-ray. Results show a good effect of HWCAs on the properties, radiation shielding and unit weight. The density of heavyweight geopolymer mixes ranges between 2,415 and 3,480 kg/m3, and HWCA ratios contribute to an increase in all properties of GC mixtures using up to 75% of NWCAs. Heavier coarse aggregate of ilmenite dampens the effect of higher temperatures on GC strength compared with lighter aggregates. In addition, replacing crushed dolomite with heavyweight aggregates of EAFSS, barite and ilmenite increases the attenuation rate to 27%, 21% and 13%, respectively. This finding confirms that the type of aggregate used in the production of GC is important for reducing the permeability of X-ray.

Experimental and numerical studies on flexural behavior of high strength concrete beams containing waste glass

Haido, James H.,Zainalabdeen, Marwa A.,Tayeh, Bassam A. Techno-Press 2021 Advances in concrete construction Vol.11 No.3

The behavior of concrete containing waste glass as a replacement of cement or aggregate was studied previously in the most of researches, but the present investigation focuses on the recycling of waste glass powder as a substitute for silica fume in high strength concrete (HSC). This endeavor deals with the efficiency of using waste glass powder, as an alternative for silica fume, in the flexural capacity of HSC beam. Thirteen members with dimensions of 0.3 m width, 0.15 m depth and 0.9 m span length were utilized in this work. A comparison study was performed considering HSC members and hybrid beams fabricated by HSC and conventional normal concrete (CC). In addition to the experiments on the influence of glass powder on flexural behavior, numerical analysis was implemented using nonlinear finite element approach to simulate the structural performance of the beams. Same constitutive relationships were selected to model the behavior of HSC with waste glass powder or silica fume to show the matching between the modeling outputs for beams made with these powders. The results showed that the loading capacity and ductility index of the HSC beams with waste glass powder demonstrated enhancing ultimate load and ductility compared with those of HSC specimens with silica fume. The study deduced that the recycled waste glass powder is a good alternative to the pozzolanic powder of silica fume.

Improving the brittle behaviour of high-strength concrete using keratin and glass fibres

Abdelsamie, Khaled,Agwa, Ibrahim Saad,Tayeh, Bassam A.,Hafez, Radwa Defalla Abdel Techno-Press 2021 Advances in concrete construction Vol.12 No.6

Keratin fibres are waste products of the poultry industry. Natural materials made from chicken feather fibres (CFFs) are used in concrete-reinforced composites in this study. Brittleness is a major problem of high-strength concrete (HSC) that leads to sudden failure at the ultimate capacity of concrete. Hence, this work aims to investigate effects of using CFFs on improving the brittle behaviour of HSC. Two scenarios are performed to analyse the effectiveness of using CFFs. HSC containing different ratios of CFF (0% as the control, 0.5%, 1%, 1.5%, 2%, and 3%) by volume are tested in the first scenario. Glass fibres (GF) are used to replace CFFs in the other scenario. Tests of fresh, hardened and morphological properties for concrete are performed. Results showed the enhanced brittle behaviour of HSC when using both types of fibres. The preferable ratio of both types of fibres is 1% by volume. Flexural and splitting tensile strengths increased by about 44.9 % and 42.65 % for mixes containing 0.1% GF, respectively. While they were increased by about 21.6 % and 21.16 % for mixes containing 0.1% CFF, respectively.