In this study practical tests for thermal conductivity are done on twenty one specimens for seven types of cement mortar contains different types of cement available in local markets for Kirkuk city in the same standard conditions. Heat flow amounts within the specimens are calculated using Fourier law for conduction. Comparison between practical results and theoretical values depended in references for calculating thermal loads in concrete walls gave good agreement. Test results for specimen No. (7) for cement of Al-Sulaimanya company gave minimum value for thermal conductivity, which was (1.162 W/m.oC), and maximum value was for specimen No. (4) for Iranian cement, which was (1.55 W/m.oC) and for specimen No. (3) for cement of Bazian company, which was (1.52 W/m.oC). Results of thermal conductivity for all the other specimens were within the depended theoretical value. Minimum heat flow within the material was for specimen No. (7) for cement of Al-Sulaimanya company, while maximum value was for specimen No. (4) for Iranian cement. Key words: thermal conductivity test, cement, mortar, heat flow, Fourier law for conduction.
A study was undertaken to produce lightweight aggregate concrete using artificial lightweight aggregate (Lytag) made from sintered fly ash. Cement or fly ash-based geopolymer was utilized as binder material, and its effect on the properties (compressive strength, water absorption, and thermal conductivity) of lightweight aggregate concrete was investigated. Two mixes were designed (using the absolute volumes method) and produced at a density of around 1350 kg/m3 as cement lightweight aggregate concrete and geopolymer lightweight aggregate concrete. Fly ash and an alkaline solution (sodium hydroxide and sodium silicate) were used to produce the geopolymer paste. The results indicated that the compressive strength, water absorption, and thermal conductivity of lightweight aggregate concrete made with geopolymer paste were better than those made with cement paste. An increase in compressive strength by about 49% and a decrease in water absorption and thermal conductivity by about 36% and 25%, respectively, were noticed in fly ash-based geopolymer lightweight mix compared to cement lightweight concrete mix.
This research work includes production of new type of light weight concrete and studies the mechanical and thermal properties. Several proportions of raw materials were used to produce this type of concrete. This study is intended to produce light weight concrete with low thermal conductivity so that it can be used for concrete masonry units. Polystyrene aggregate was added as percentages by weight of cement to improve the thermal properties of this type of concrete .Mechanical , and thermal tests with difference ages were made in this work .For polystyrene concrete with polystyrene cement ratio (p/c) of (2.67 – 6 )% , the28-day compressive strength range is from (4.31 – 2.67)MPa, flexural strength range is from (3.05-1.719 ) MPa , density range is from ( 1493-1213 ) kg/m 3 ,and thermal conductivity range is from ( 0.91-0.782)% as a percentage by that of reference mix. The study show suitability of this type of concrete to be used in concrete masonry units of non-bearing walls.
Concrete is by far the most widely used construction material now today. Foamed concrete is light building material with good strength as well as low thermal conductivity and easy workability; it is produced by either Mix Foam Method or Preformed Foam Method. Ultrasonic Pulse Velocity(UPV) is a non destructive technique involve measuring the speed of sound through concrete in order to predict concrete strength and to detect the presence of cracking, voids, decay and other damages. This research includes three main experimental stages:- The first stage includes the production of foamed concrete and it was divided into two parts, the first part, mixing design(determination the proportions of the raw materials) was presented in the second part, the mixing procedure has been illustrated. The second stage includes preparation of samples,(i.e. molding, finishing surface, removal from molds, and curing). The third stage includes several teste to estimate properties the final product and factors influencing them, these properties include density, compressive strength, and the ultrasonic pulse velocity. From the experimental work and at the same test's age, the compressive strength and the ultrasonic pulse velocity for foamed concrete with 800 kg/m3 density were respectively (2.38 MPa,1.56 km/s)and the compressive strength and the ultrasonic pulse velocity for foamed concrete with 1200 kg/m3 density were respectively (3.7 MPa,1.96 km/s) while it were (7.8 MPa and 2.12 km/s) for foamed concrete with 1600 kg/m3 density
This study addressed some important tests for concrete including thermal, acoustic insulation and some mechanical behaviour of concrete containing granular Polyvinyl Chloride (PVC) waste as a sand replacement. The PVC waste was collected from a plant of manufacturing PVC doors and windows, was used to replace some of fine aggregate at ratios of 2.5%, 5%, 7.5%, 10%, 12.5% and 15% by weight Properties that studied are thermal conductivity, acoustic insulation slump, fresh density, dry density, compressive strength, flexural strength, and splitting tensile strength. Curing ages of 7, 28, and 56 days for the concrete mixtures were applied in this work. From the results of this study, it is suggested that using of 12.5% fine PVC as a sand replacement by weight can improve thermal insulation to about 82.48% more than concrete without plastic waste Acoustic insulation is about 43.09% more than reference mix and it satisfies the requirement of ACI 213R 2014 for structural lightweight concrete.