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Effect of cement dosing without additions (CPA) on high-performance and ordinary concrete based glass powder as fine partial cement replacement - a comparative study

Aissat-Arab Bahia, Mehaddene Rachid

Advances in Materials Science

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2024

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Vol. 24, nr 1(79)

17--31

EN

The main objective of this paper research is a comparative study on the effect of the glass powder (GP) substitute from collected and recycled glass waste, as a fine partial cement replacement on the mechanical performance and durability of high performance concrete (HPC) and ordinary concrete (OC). For this two cement dosing were used of 400 kg/m3 to formulate OC and 450 kg/m3 to formulate HPC, and GP as considered binder like cement and not as fine addition, hence binder represent the sum of cement with GP (L=C+GP) with which will be made our two concretes formulation. Two ratios were used for the Water/Binder (W/B), the first W/B=0.35 for the HPC and the second W/B=0.5 for the OC, this ration is very important to fix the concentration of superplasticizer. A percentage of 10% and 20% substitution of cement CPA without additions noted CEM I 52.5 by the glass powder with fineness of 3600 cm 2/g are used. The evaluation of the compressive strength was followed from 7 to 365 days in order to study the behavior of the GP at different ages affected by the cement dosing and the ratio W/B compared to the reference concrete without GP for the two concretes HPC and OC. At 28 days the strengths of concretes with GP is affected by the replacement of a quantity of cement since the two reference concretes were superior but beyond this age an inverse behavior is noticed such that results obtained at age of 365 days seem to be advantageous in terms of savings in the quantity of cement used by interpreting the compressive strength, and the decrease in quantity of water in the mixtures offers a remarkable difference between the two concretes studied by using 20 % of GP as replacement of cement.

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Partial replacement of cement with rice husk ash in concrete production: an exploratory cost-benefit analysis for low-income communities

Muleya Franco, Muwila Natasha, Tembo Chipozya K, Lungu Alice

Engineering Management in Production and Services

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2021

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Vol. 13, no. 3

127--141

EN

Cement is an important construction material in concrete production; however, it is expensive and unaffordable for many low-income and rural communities in developing countries. Rice husk is a by-product from the rice mill process, with an approximate ratio of 200 kg rice husk per one tonne of rice produced. This experimental study aimed to investigate the integrity of concrete produced in Zambia using rice husk ash (RHA) to partially replace cement. The primary goal was to carry out a cost–benefit analysis on the use of RHA in concrete. RHA was used to partially replace cement with ratios of 10 %, 20 % and 30 %. The 20 % cement replacement mix produced the optimum 18 MPa concrete strength results at a 0.5 water/binder ratio. This translated in cost reduction of concrete by 12.5 %, which is particularly significant for higher concrete volumes. The produced concrete is suitable for lightly loaded structures, such as foundation footings, surface beds and walkways to benefit low-income communities. The study further concluded that the RHA based concrete was more cost-efficient in structures that were close to areas of rice production due to reduced RHA transportation costs.

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Experimental investigation of using recycled glass waste as fine aggregate replacement in concrete

Alharishawi Salam Salman Chiad, Rajaa Nagham, Jabur Aqeel Raheem

Archives of Civil Engineering

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2021

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Vol. 67, nr 4

27--38

EN

Environmental problems are considered a serious situation in modern construction. Reusing and recycling glass wastes is the only method to decrease waste produced. There is growing environmental compression to decrease glass waste and to reprocess as much as possible. In this investigational work, the effect of partially substituting crushed waste glass in concrete is considered. The study investigates crushed waste glass used as a partial replacement of fine aggregate for new concrete. Recycled glass waste was partially replaced as 5%, 10%, 15%, 20%, 25%, 30, 35, 40%, 45%, 45% and 50% and tested at 7, 14 and 28 days of curing at 20° for mechanical properties and compared with those of controlled mix. The compressive strength, splitting tensile strength and flexural forces and static elasticity modulus of specimens with 20% waste glass content was 30%, 19.41%, 9.13% and 10.12%, respectively, which is higher than the controlled mix at 28 days. The outcomes displayed that the maximum rise in strength of concrete occurred when 20% replacement with glass crush. It is found that crushed waste glass can be used as fine aggregate replacement material in concrete production.