Characteristics of CO2 and Energy-Saving Concrete with Porous Feldspar

Abstract

In this study, to reduce the use of cement and sand, porous feldspar with excellent economic efficiency was used as a substitute in the heat storage concrete layer. When porous feldspar and four other silicate minerals were used as substitute materials for sand in cement mortar, the specimen with the porous feldspar exhibited approximately 16–63% higher compressive strength, thereby exhibiting a higher reactivity with cement compared to the other minerals. To compensate for the reduction in strength owing to the decreased cement content, mechanical and chemical activation methods were employed. When the specific surface area of porous feldspar was increased, the unit weight was reduced by approximately 30% and the compressive strength was increased by up to 90%. In addition, the results of the thermal diffusion test confirmed that thermal diffusion increased owing to a reduction in the unit weight; the heat storage characteristics improved owing to the better porosity of feldspar. When chemical activation was performed after reducing the cement content by 5% and replacing the sand with porous feldspar, the compressive strength was found to be approximately twice that of an ordinary cement mortar. In a large-scale model experiment, the heat storage layer containing the porous feldspar exhibited better heat conduction and heat storage characteristics than the heat storage layer composed of ordinary cement mortar. Additionally, energy savings of 57% were observed.

Special Issue: Supplementary Cementitious Materials in Concrete, Part I

“…properties of modified cement matrix composites reinforced with fibers [14,[18][19][20]; • application of new types of supplementary cementitious materials [13,16,[21][22][23][24][25][26][27][28]; • characterization of various types of modified cement based materials [18,21,23,[25][26][27][28][29][30][31].…”

“…The issues of the original research papers and stat-of-the art reviews published in this Special Issue of Materials, and coming from over 45 international universities and scientific centres, can be divided as follows: permeability and diffusivity, which are directly related to the quality of concrete and to the durability in various aggressive environments [ 13 , 14 , 15 , 16 , 17 ]; properties of modified cement matrix composites reinforced with fibers [ 14 , 18 , 19 , 20 ]; application of new types of supplementary cementitious materials [ 13 , 16 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]; characterization of various types of modified cement based materials [ 18 , 21 , 23 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ]. …”

“…characterization of various types of modified cement based materials [ 18 , 21 , 23 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ].…”

“…Han et al [ 31 ] investigated the application of porous feldspar to reduce the use of cement and sand in the heat storage concrete layer. The mechanical and chemical activation methods were used to compensate the reduction of strength, due to the lower content of cement.…”

Effect of Hydrogen Nanobubbles on the Mechanical Strength and Watertightness of Cement Mixtures

“…To this end, studies on alternative (substitute) materials and durability-enhancement methods for reducing cement usage have recently been conducted. Granulated blast-furnace slag, ultrafine granulated copper slag, and porous feldspar have been used as cement-replacement materials to reduce cement content while improving its mechanical properties [ 8 , 9 , 10 ].…”