Synergistic effects of fly ash and hooked steel fibers on strength and durability properties of high strength recycled aggregate concrete

In this study, bentonite (a naturally occurring pozzolana) was incorporated as a partial replacement (up to 20%) for high-calcium fly ash (HCFA)-based geopolymeric natural aggregate concrete (GNAC) and geopolymeric recycled aggregate concrete (GRAC). The mechanical (compressive strength and splitting tensile strength), durability (chloride migration coefficient, water absorption, and acid attack resistance), and rheological properties (slump test, fresh density, and workability) were investigated. The results revealed that incorporation of bentonite (10 wt % with ordinary Portland cement) showed appreciable improvement in the strength and durability of both the GNAC and GRAC, though its effect is more significant for GRAC than the GNAC.

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A Study of the Strength and Durability Properties on Recycled Aggregate Concrete and Blain of Blast Furnace Slag

Journal of the Korea Institute of Building Construction ◽

10.5345/jkic.2007.7.4.101 ◽

2007 ◽

Vol 7 (4) ◽

pp. 101-108 ◽

Cited By ~ 2

Author(s):

Myung-Kwan Lim ◽

Moo-Young Park ◽

Sang-Jin Jung

Keyword(s):

Blast Furnace ◽

Blast Furnace Slag ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Aggregate Concrete ◽

Durability Properties ◽

Strength And Durability ◽

Furnace Slag

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Effect of Mineral Admixtures on the Performance of Low-Quality Recycled Aggregate Concrete

Crystals ◽

10.3390/cryst11060596 ◽

2021 ◽

Vol 11 (6) ◽

pp. 596

Author(s):

Yasuhiro Dosho

Keyword(s):

Blast Furnace ◽

Fly Ash ◽

Blast Furnace Slag ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Mineral Admixtures ◽

Structural Concrete ◽

Aggregate Concrete ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

To improve the application of low-quality aggregates in structural concrete, this study investigated the effect of multi-purpose mineral admixtures, such as fly ash and ground granulated blast-furnace slag, on the performance of concrete. Accordingly, the primary performance of low-quality recycled aggregate concrete could be improved by varying the replacement ratio of the recycled aggregate and using appropriate mineral admixtures such as fly ash and ground granulated blast-furnace slag. The results show the potential for the use of low-quality aggregate in structural concrete.

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Recycling of Waste Concrete and Fly Ash for Recycled Aggregate Concrete: Fundamental Characteristics Evaluation

Materials Science Forum ◽

10.4028/www.scientific.net/msf.620-622.255 ◽

2009 ◽

Vol 620-622 ◽

pp. 255-258 ◽

Cited By ~ 1

Author(s):

Cheol Woo Park

Keyword(s):

Fly Ash ◽

Recycled Concrete ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Experimental Program ◽

Concrete Aggregate ◽

Fine Aggregate ◽

Recycled Concrete Aggregate ◽

Aggregate Concrete ◽

Waste Concrete

As the amount of waste concrete has been increased and recycling technique advances, this study investigates the applicability of recycled concrete aggregate for concrete structures. In addition fly ash, the industrial by-product, was considered in the concrete mix. Experimental program performed compressive strength and chloride penetration resistance tests with various replacement levels of fine recycled concrete aggregate and fly ash. In most case, the design strength, 40MPa, was obtained. It was known that the replacement of the fine aggregate with fine RCA may have greater influence on the strength development rather than the addition of fly ash. It is recommended that when complete coarse aggregate is replaced with RCA the fine RCA replacement should be less than 60%. The recycled aggregate concrete can achieve sufficient resistance to the chloride ion penetration and the resistance can be more effectively controlled by adding fly ash. It I finally conclude that the recycled concrete aggregate can be successfully used in the construction field and the recycling rate of waste concrete and flay ash should be increased without causing significant engineering problems.

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