文章基本信息

标题：Production of Geopolymeric Mortars Containing Forest Biomass Ash as Partial Replacement of Metakaolin
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作者：Sebastiano Candamano ; Pierantonio De Luca ; Patrizia Frontera 等
期刊名称：Environments
电子版ISSN：2076-3298
出版年度：2017
卷号：4
期号：4
页码：74
DOI：10.3390/environments4040074
语种：English
出版社：MDPI Publishing
摘要：Geopolymers are a new class of binders based on alkali activation of natural and by-products raw materials. Their properties and eco-compatibility highly depends on the reaction system. The (Na,K)2O-Al2O3-SiO2-H2O system shows a distinguishing pseudo-zeolitic network structure, but reaction requires a high amount of activators. The aim of this work is to investigate how the use of forest biomass ash (FBA), as partial replacement material in the production of metakaolin (MK) based geopolymeric mortar, and affect its properties. FBA is a by-product of the combustion process of forest biomass in thermal power plants. Mortars with a FBA content of 0%, 10%, 20%, and 30% wt have been tested for workability, flexural, and compressive strength. Capillary absorption, micro-morphological features, thermal, and shrinkage behavior have been investigated. The addition of FBA allowed for a decrease in the use of alkaline activator up to 20%, while preserving the characteristic broad hump centered at approximately 28° 2θ Mechanical properties of the geopolymeric mortars decrease proportionally with metakaolin replacement, even if a compression strength of more than 35 MPa is still obtained with a FBA content of 30% wt. After thermal cycles of up to 700 °C, all of the mortars still retain their cohesiveness, with an overall loss of mechanical strength of about 80% of the initial value that can be attributed to the formation of microcracks as a consequence of the network strain and distortion due to dehydration and shrinkage.
关键词：forest biomass ash; geopolymeric mortar; workability; mechanical properties; capillary water absorption forest biomass ash ; geopolymeric mortar ; workability ; mechanical properties ; capillary water absorption