000002091 001__ 2091
000002091 005__ 20141118153443.0
000002091 04107 $$acze
000002091 046__ $$k2013-05-27
000002091 100__ $$aKATPADY, Dhruva N.
000002091 24500 $$aEXPERIMENTAL STUDY ON REACTIVITY OF PYROCLASTIC FLOW DEPOSIT CALLED SHIRASU AS BINDER IN MORTAR AND GEOPOLYMER

000002091 24630 $$n1.$$pProceedings of the First International Conference on Concrete Sustainability
000002091 260__ $$bJapan Concrete Institute, Tokyo
000002091 506__ $$arestricted
000002091 520__ $$2eng$$aThe study aims at using Shirasu, which is a pyroclastic flow deposit like volcanic ash, as one of the binders in mortar or concrete. It is one of the unused natural resources, available in Kyushu Island of Japan, and pose potential threat to environment and health. From the view points of effective use of the unused natural resource and CO2 free material, Shirasu is used as a cement replacement material. In the experiment, size under 150μm of “Shirasu” is used. Comparison between strengths of mortars using Shirasu with the ones made of ordinary Portland cement mortars or mortars with fly ash partially replacing cement is done up to 1 year curing. From test results of the mortars in which the Shirasu replacement levels of 10%, 20%, 30% in binder and water binder ratio of 40%, 50% and 60%, the mortar having 10% of Shirasu replacement level with water binder ratio of 40% shows optimum mechanical property up to 1 year. Geopolymer has lately attracted considerable attention as one of the CO2 free construction materials, because of concrete free from any cementitious material. Therefore, an attempt is made to study Shirasu as aluminosilicate source in geopolymer. Geopolymer mortar is made with Shirasu of size under 75μm, chemical admixtures of NaOH and Na2SiO3 as alkaline activators, and river sand. Three types of water binder ratio, 40%, 50%, 60% are set and heat cured at 80ºC and 90ºC. The mixture polymerizes under high temperature to form hard mass which is subjected to compressive strength test. From the results obtained, the compressive strength is highest for water to binder ratio of 40% under 90ºC of curing condition. The strengths are also compared with geopolymer mortars using fly ash as binder and the ones with fly ash as binder and Shirasu as fine aggregate. KEYWORDS: shirasu, pyroclastic flow deposit, CO2 free material, geopolymer, alkaline activators

000002091 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000002091 653__ $$a

000002091 7112_ $$aFirst International Conference on Concrete Sustainability$$cTokyo (JP)$$d2013-05-27 / 2013-05-29$$gICCS13
000002091 720__ $$aKATPADY, Dhruva N.$$iYAMAGUCHI, Toshinobu$$iTAKEWAKA, Koji
000002091 8560_ $$ffischerc@itam.cas.cz
000002091 8564_ $$s1735651$$uhttp://invenio.itam.cas.cz/record/2091/files/S1-6-4.pdf$$y
             Original version of the author's contribution as presented on CD, .
            
000002091 962__ $$r2053
000002091 980__ $$aPAPER