Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6749651 | Journal of Building Engineering | 2018 | 9 Pages |
Abstract
Foam stabilizer plays a crucial role in the synthesis of geopolymer foam materials (GFMs). To better clarify the effects of calcium stearate based foam stabilizer (CSFS) on pore characteristics and thermal conductivity of materials, GFMs prepared with 0-2% CSFS were investigated for foam characterization, compressive strength, bulk density, geopolymerization products, pore distribution, and thermal conductivity. Results shows that (1) the foam time and initial setting time match optimally with 1.0% CSFS content. And at this point, the foam time and foam volume of GFMs were increased obviously by 42.8% and 28.6% respectively. (2) 28â¯d compressive strength of GFMs with a bulk density of 0.31â¯g/cm3 at 1.0% CSFS content were the lowest, 1.45â¯MPa, but still better than the standard of 1.0â¯MPa for 0.325â¯g/cm3 according to the Chinese National Standards GB11968-2006. (3) CSFS displayed limited effect on the quantity or type of geopolymerized products. (4) With CSFS/FA increasing from 0.5% to 2.0%, The quantity of macroscopic scale pores sized 10-100â¯Âµm rose considerably and then drop obviously, but still more than that of sample with free CSFS. The quantity of microscopic scale pores sized 10-100â¯nm grew stably. (5) Overall, 1.0% CSFS optimized pore characterization well with a largest porosity, 82%, where the thermal conductivity of GFMs reached a bottom point at 0.095â¯W/(mâ¯K). (6) The relationship between thermal conductivity and total porosity conforms to a Maxwell-Euchen or modified Cheng-Vachon model and the value of parameter t is determined as 1.1.
Related Topics
Physical Sciences and Engineering
Engineering
Civil and Structural Engineering
Authors
Yong Cui, Dongmin Wang, Jihui Zhao, Duanle Li, Serina Ng, Yafeng Rui,