Preparation, Properties and Microstructure of Non-Calcination Rock Powder Brick with Orthogonal Experiments

Abstract

In this paper, the preparation method and reasonable mix ratio of non-calcination brick with rock powder, cement, lime and fly ash ceramsite (FAC) as the raw materials were experimentally evaluated. To better understand the effects of each component on the performance of non-calcination rock powder brick (NCRPB), an orthogonal experimental design was conducted with the water–cement ratio (W/C), rock powder–cement ratio (R/C), lime content (wl) and FAC content (wf) as the main factors, which involved four factors and three factor levels. According to the orthogonal experimental design, the compressive strength, water resistance and bulk density of nine groups of NCRPB specimens were tested. The results show that R/C was the most important factor affecting the compressive strength and water resistance, while the FAC content influenced the bulk density of NCRPB greatly. In this study, the reasonable mix of W/C, R/C, wl, and wf in weight was 0.6, 3.0, 30% and 21%, respectively. In addition, the microstructure and strength formation mechanism of NCRPB were analyzed by using SEM and XRD. The test results show that the rock powder having pozzolanic activity could react with the additional Ca(OH)2 to produce hydration products, leading to the improvement of the performance of NCRPB.

Influence of Brick Powder with Different Replacement Ratio on Concrete Performance and its Microscopic Mechanism

“…[4,5] Due to the disadvantages of waste bricks, themselves can't be used repeatedly, research has shown that brick powder has a pozzolanic effect and can be used as a partial substitute for cement in construction production, on the one hand, it can solve the problem of cement energy consumption, on the other hand, it also solves the environmental problems of waste bricks. [6,7] Due to the slow pozzolanic effect of brick powder, in the present study, the main focus is on the study of the excitability of brick powder. [8] In general, the appropriate amount of brick powder will not cause harm to the performance of concrete, but the addition of excessive brick powder will affect the performance of concrete.…”

Research on the Preparation and Mechanical Properties of Solidified 3D Printed Concrete Materials

“…Determining the influence of different admixtures on the performance of concrete through single-factor experiments: an orthogonal combination test [13] has been used to analyze the interaction between different factors to determine the basic mix ratio of printed concrete. According to the requirements of the 3D printing process, fiber optimization is conducted, and the mix ratio of fiber-reinforced concrete is determined.…”