Coupling effects of recycled aggregate and GGBS/metakaolin on physicochemical properties of geopolymer concrete

Xie, Jianhe; Chen, Wei; Wang, Junjie; Fang, Chi; Zhang, Bingxue; Liu, Feng

doi:10.1016/j.conbuildmat.2019.07.311

Cited by 118 publications

(37 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Geopolymer is a material that has attracted wide interests among many scientists around the world due to its excellent properties which include high compressive strength, low shrinkage, acid, and fire resistance [4][5][6]. Studies have been conducted on different forms of geopolymer including geopolymer concrete [7,8], precast paving cement-free brick [9], and lightweight geopolymer composite [10]. As an inorganic polymer which is based on synthetic aluminosilicate materials [11], geopolymer has a potential in coating application as a surface protector and insulator for various surfaces including metal [12].…”

Section: Introductionmentioning

confidence: 99%

Optimization of Rice Husk Ash-Based Geopolymers Coating Composite for Enhancement in Flexural Properties and Microstructure Using Response Surface Methodology

et al. 2020

View full text Add to dashboard Cite

If the coating is sufficiently flexible, no tears, cracks, or debond will occur. Although geopolymers have a great potential as a coating material, research on the flexural properties is very limited. In this study, a three-point bending test and scanning electron microscope were used to investigate the flexural properties and microstructure of the geopolymer composite coating (GCC), respectively. Response Surface Methodology (RSM) consists of a combination of mathematical and statistical techniques, which is useful in modelling, analyzing, and optimizing responses that are influenced by several factors. It was used in determining the relationship between each factor and determining the best composition for the composite coating. Several factors were considered including ratio of activated alkaline (AA) solution (V1), RHA/AA ratio (V2), and curing temperature (V3). Results showed that the RHA/AA ratio mostly influenced the response, followed by curing temperature while the ratio of AA was not significant. Lower V2 and V3 values provided the highest flexural strength and modulus. The optimum composition which provided the best coating of flexural properties were V1 = 3.5, V2 = 0.39, and V3 = 45.7 °C. Microscopic images showed that coating with high flexural properties (ductile coating) exhibited minor and rough cracks as compared to that of coating with low flexural properties (brittle coating) which displayed a crack with a clean linear cut. Brittle coating was highly agglomerated and has a significant negative effect on the flexural properties. By developing the optimum composition, the GCC may potentially be a good alternative as a building construction coating material.

show abstract

Section: Introductionmentioning

confidence: 99%

Optimization of Rice Husk Ash-Based Geopolymers Coating Composite for Enhancement in Flexural Properties and Microstructure Using Response Surface Methodology

et al. 2020

View full text Add to dashboard Cite

show abstract

“…There are also studies confirming that improvements in geopolymer properties can be obtained through the addition of GGBS (Granulated Blast-Furnace Slag). Additionally, such arrangements contribute to the management of waste from the building industry [20,21].…”

Section: Introductionmentioning

confidence: 99%

Decreasing of Leaching and Improvement of Geopolymer Properties by Addition of Aluminum Calcium Cements and Titanium Oxide

et al. 2020

View full text Add to dashboard Cite

The article presents the latest results of the leaching of alkali from geopolymers depending on the introduced additions in the form of aluminum calcium cement and nanometric titanium oxide. Aluminum calcium cements were introduced in two variants: G40 (>40% Al2O3) and G70 (>70% Al2O3) in amounts of 0%, 2%, and 4% by weight. Titanium oxide was also incorporated in amounts of 2% and 4% by weight. The results of conductivity tests of solutions in which geopolymers were immersed were carried out. On this basis, it was found that geopolymers cured in the aquatic environment have a lower risk of efflorescence in the later periods of their use due to leaching of compounds at the stage of aquatic curing. In addition, it was found that the addition of calcium aluminum cements decreases the leaching of substances from geopolymers. It was also found that geopolymers based on an 8 M NaOH solution have greater leaching than when using a 10 M solution. The results of the compressive strength tests for the tested samples were also presented.

show abstract

“…Compared with other supplementary cementitious materials, MK has many advantages, including higher activity, larger specific surface, and finer particle size [17]. Studies have emerged that offer contradictory findings about the effects of MK content on physical and mechanical properties of cement soil and concrete materials and acquired abundant accomplishment [15,16,[18][19][20][21][22][23]. Wu et al [15] studied the effect of MK contents on the strength performance of cement-modified soil, and test results reveal that both the unconfined compression and splitting tensile strengths are improved, and the suitable ratio of MK to cement ranges from 1/3 to 1/2.…”

Section: Introductionmentioning

confidence: 99%

Effects of Curing Time on the Mechanical Property and Microstructure Characteristics of Metakaolin‐Based Geopolymer Cement‐Stabilized Silty Clay

Zhang

2020

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

Metakaolin (MK), which has a fine particle size and higher activity in high alkaline environments, has been widely used in the fields of soil treatment engineering to stabilize soils. MK is used to replace part of ordinary Portland cement (OPC) with 0 : 15, 2 :13, 4 : 11 and 6 : 9 mass ratios of MK to OPC in this study. The mechanical property (e.g. stress-strain relationship, strength, and deformation performance) and microstructure characteristics of MK-based geopolymer cemented silty clay are investigated using unconfined compressive strength (UCS), nuclear magnetic resonance (NMR), and scanning electronic microscopy (SEM) tests. In addition, strength increase coefficient (ζs) and elasticity modulus increase coefficient (ζe) are defined to evaluate the effects of curing time on the mechanical property of MK-based geopolymer cemented silty clay. Moreover, the relationships among porosity, UCS, and E50 of MK-cemented silty clay are studied. By incorporating 2% MK, the UCS and E50 of MK-cemented silty clay at 28 d are 1.32 and 1.30 times compared with MK0 group, respectively. The increase rate of UCS and E50 from 1 d to 7 d is faster compared with that from 7 d to 28 d. Furthermore, the microstructure of the sample modified by 2% MK is most homogeneous and dense. Finally, the optimistic mass ratio between MK and cement is 2 : 13 for silty clay in this test condition.

show abstract

Coupling effects of recycled aggregate and GGBS/metakaolin on physicochemical properties of geopolymer concrete

Cited by 118 publications

References 72 publications

Optimization of Rice Husk Ash-Based Geopolymers Coating Composite for Enhancement in Flexural Properties and Microstructure Using Response Surface Methodology

Optimization of Rice Husk Ash-Based Geopolymers Coating Composite for Enhancement in Flexural Properties and Microstructure Using Response Surface Methodology

Decreasing of Leaching and Improvement of Geopolymer Properties by Addition of Aluminum Calcium Cements and Titanium Oxide

Effects of Curing Time on the Mechanical Property and Microstructure Characteristics of Metakaolin‐Based Geopolymer Cement‐Stabilized Silty Clay

Contact Info

Product

Resources

About