Sorption and Thermal Properties of Insulating Mortars with Expanded and Vitrified Small Ball

Abstract

Sorption and thermal properties of insulating mortars with expanded and vitrified small ball (EVSB)Ping, F.; Mukhopadhyaya, P.; Kumaran, M. K.; Shi, C.http://www.nrc-cnrc.gc.ca/irc Sorpt ion a nd t he rm a l prope rt ie s of insula t ing m ort a rs w it h e x pa nde d a nd vit rifie d sm a ll ba ll (EV SB) NRCC-54004Ping, F.; Mukhopadhyaya, P.; Kumaran, M.K.; Shi, C. March 2011A version of this document is published in / Une version de ce document se trouve dans: Testing and Evaluation, 39, (2), pp. 1-32, March 01, 2011 The material in this document is covered by the provisions of the Copyright Act, by Canadian laws, policies, regulations and international agreements. Such provisions serve to identify the information source and, in specific instances, to prohibit reproduction of materials without written permission. For more information visit http://laws.justice.gc.ca/en/showtdm/cs/C-42 ASTM Journal ofLes renseignements dans ce document sont protégés par la Loi sur le droit d'auteur, par les lois, les politiques et les règlements du Canada et des accords internationaux. Ces dispositions permettent d'identifier la source de l'information et, dans certains cas, d'interdire la copie de documents sans permission écrite. Pour obtenir de plus amples renseignements : http://lois.justice.gc.ca/fr/showtdm/cs/C-42 Sorption and Thermal Properties of Insulating Mortars with Expanded and Vitrified Small Ball (EVSB)Ping Fang 1* , Phalguni Mukhopadhyaya 2 , Kumar Kumaran 2 , Caijun Shi 1 , ABSTRACT:Expanded vitrified small hollow ball (EVSB), made from a special type of perlite mineral is one of the recently developed materials in China. It is widely used as a cementitious thermal insulating mortar for building envelope construction in hot-humid areas of southern China. However, EVSB is a porous material sensitive to environmental moisture. The thermal insulating property of the EVSB mortar is dependent on its moisture transport and storage characteristics. In this study, hygroscopic sorption properties of EVSB mortars have been investigated, in comparison with those of normal expanded perlite particle (NEPP) mortars. The BET specific surface area and the BJH pore size distribution, as well as the SEM micro-morphologies of the mortars were assessed. It was observed that EVSB mortars had lower moisture sorption capacity than NEPP mortars when the relative humidity (RH) was higher than 70% because of its lower total pore volume. The addition of water-repellent admixtures in the mortar decreased the moisture sorption capacity of EVSB mortars but still maintains the same physisorption isothermal characteristics. It is also evident that the thermal conductivity values of both NEPP and EVSB mortars increased rapidly when RH is above 90%. However, the increase rate of thermal conductivity of NEPP mortars was apparently higher than that of EVSB mortars. It is hoped that finding from this study will help to develop a better understanding of the in-situ thermal performance of EVSB mortar used for the building envelope construction in...

Investigation and Preparation of the Plastering Mortar for Autoclaved Aerated Blocks Walls

“…EVSB is a hollow low-density spherical particle with a vitrified surface, and provides high fluidity during the mixing process [25,38,43]. Hence, the particles can easily float in the mortar, which seriously affects the serviceability of the mortar.…”

“…The formation of the plaster layer of AABs from lightweight aggregates was considered to be the key to solving the "thermal bridges" effect [21,22]. Researchers have explored the potential of cork granules [23], perlite microspheres [24], expanded and vitrified small ball [25], air entraining agents [26,27], expanded vermiculite [28], phase change material [29], and expanded polystyrene beads [30]. Li et al [18] concluded that the heat transfer coefficient of plastering mortar is 0.48 W/(m•K), in which expanded perlite, vitrified microsphere, and 0.04% polypropylene fiber were added to prevent the shrinkage and cracking of the mortar.…”