Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : High reactivity Attapulgite


The Synergic Effect of Fly Ash and High Reactivity Attapulgite in Ternary Blended Cement

Shubbar J. Al-Obaidey

Engineering and Technology Journal, 2019, Volume 37, Issue 12A, Pages 528-535
DOI: 10.30684/etj.v37i12A.456

The main objective is to study the synergic effect of fly ash (FA) and high reactivity Attapulgite (HRA) together in ternary blended cement of (OPC+FA+HRA) and evaluate the efficiency factor of FA and HRA in binary blended cement and (FA+HRA) in ternary blended cement. To achieve this objective compressive strength of binary blended cement mixes of (OPC+FA) with FA replacement percentages of (20 %, 30% and 40%), (OPC+HRA) with HRA replacement percentages of (5 and 10%) by weight of cement and ternary blended cement mixes of (OPC+FA+5% and/or 10%HRA). Were tested and compared with that of reference mix at ages of (7, 28, 56 and 90) days to assess the synergic effect of FA and HRA in ternary blended cement. The results showed that using ternary blended cement of (OPC+FA+5% and/or 10%HRA) led to increasing compressive strength relative to binary blended cement mixes of (OPC+FA) at the same replacement percentages by weight of cement. More significant increments in compressive strength were noticed at the age of 7 days. The results also showed that the efficiency factors calculated according to the modified bolmoy΄s equation for ternary blended cement were always higher than their corresponding binary blended cement of (OPC+.FA).

The Effect of Using Multi Types of Mineral Admixtures on Some Properties of Lightweight Self-Compacting Concrete

Waleed A. Razaq; Qais J. Freih; Shubbar J. Al Obaidey

Engineering and Technology Journal, 2019, Volume 37, Issue 1C, Pages 186-194
DOI: 10.30684/etj.37.1C.29

The main objective of this research was studying the effects of using multi types of mineral admixtures as high reactivity Attapulgite (HRA), high reactivity Metakaolin (HRM) and fly ash (FA) on some rheological and mechanical properties of lightweight self - Compacting concrete (LWSCC), when were used as a partially replacement by weight of cement. The results showed that using of (HRA) and (HRM) increased the superplasticizer (SP) dosage, while (FA) with spherical particles reduced the (SP) dosage relative to reference mix (Ref. mix) to get the same slump flow target value. The optimum content for (HRA) used in this study was 10 %, and the percentages of increment in compressive strength and splitting tensile strength relative to (Ref.mix) were (10.0%, 12.2%, 11.15% and 12.3%) and ( 8.8%, 17.46%, 16.34% and 14.66%) for 7, 28, 56 and 90 days respectively. Using of (FA) reduced early age strength, but long term strength increased with (FA) content increases. LWSCC mix contained 10% (HRM) showed a better mechanical properties than both (HRA) and (FA) LWSCC mixes, and the percentages of increment when cement was replaced with 10 % (HRM) relative to (Ref.mix) were (15.0%, 17.6%, 13.9% and 15.7%) and (16.0%, 24.2%, 22.2% and 21.6%) at 7, 28, 56, and 90 days for compressive strength and splitting tensile strength respectively.

The Combined Effect of Attapulgite High Reactive Mineral Admixture and Superplastisizer on Compressive Strength of Attapulgite Lightweight Aggregate Concrete

Qais J. Frayyeh; Waleed A. Abbas; Ali K. Hassan

Engineering and Technology Journal, 2016, Volume 34, Issue 12, Pages 2181-2192

The goal of this study , mainly is to investigate thecombined effects of using both Attapulgite high reactive mineral admixture and superplastisizer on the compressive strength of Attapulgite lightweight aggregate concrete ALWAC and some properties of sconcrete . The used coarse lightweight aggregate was made from Attapulgite clays with maximum size of 19 mm , and the optimum percentages of addition for both mineral and chemical admixture was 6% partial replacement from cement for Attapulgite mineral admixture and 0.5 L/100 kg cement for the superplastisizer used .The gained percentages of enhancement for compressive strength was (12.2%,12.6% and 16.3%) for curing ages of 7, 28 and 56 respectively as compared with the referenced plane mix when only the Attapulgite mineral admixture to be added , while the combined effect of both admixtures was clear by the percentages of ( 19.3% , 15.5% and 25% ) for curing ages 7,28 and 56 respectively as compared to the plane referenced mix . The obtained equilibrium density of ALWAC was 1818 kg/m3 ( ACI 213r-03 , less than 1840 kg/ m3 for structural purposes)for the concrete mix containing the two admixtures . The water absorption of ALWAC was reduced by the addition of the Attapulgite mineral admixture by (4% , 4.85% and 4.9% ) at 7,28 and 56 days of curing respectively but, using the superplastisizer cause an increase in water absorption and the percentages above get lowered to (2% , 3% and 2.6% ) at the ages of 7,28 and 56 days respectively .

Fresh and Hardened Properties ofLightweight Self CompactingConcrete Containing Attapulgite

Waleed A. Abbas; Qais J.Frayyeh; Shubbar J. Al Obaidey

Engineering and Technology Journal, 2016, Volume 34, Issue 9, Pages 1767-1781

The main objectives of this study were investigating the possibility of producing lightweight self -Compacting concrete (LWSCC) by using artificial coarse lightweight aggregate manufactured by burning locally available Attapulgite clay, estimating the optimum dosage of high reactivity Attapulgite (HRA) and studying its effects on fresh and hardened properties of LWSCC when using it as a partial replacement by weight of cement.Tests results showed that, It is possible to produce (LWSCC) by using Attapulgite as artificial coarse (LWA) and (HRA).The optimum content for (HRA) used in this study was 10 %, the percentages of increment in compressive strength and splitting tensile strength with 10% (HRA) relative to reference mix were (10.0%, 12.1%, 11.1% and 12.4%) and ( 12.0%, 18.2%, 16.6% and 16.2%) for 7, 28, 56 and 90 days respectively.The values of the calculated equilibrium density ranged between (1788 and 1829) kg/m3