The Study on the Whole Stress–Strain Curves of Coral Fly Ash-Slag Alkali-Activated Concrete under Uniaxial Compression

Abstract

This study aimed to research the whole stress–strain curves of coral Fly Ash-Slag Alkali-Activated Concrete (CAAC) in different strength grades. Fly ash-slag alkali-activated concrete was used as cementing materials to produce coral aggregate concrete. A monotonic loading test was conducted on the prismatic specimens to obtain elastic modulus (Ec), Poisson’s ratio (μ) and the constitutive relationship of CAAC under uniaxial compression. When the strain of CAAC reached the maximum value, the specimen was split and damaged rapidly. As the strength grade increased, the ratio of residual stress (σri) to peak stress (σ0i) decreased in the range of 0.17–0.28. The Ec of CAAC increased gradually, and μ increased to the peak value and then decreased. According to the test results, the constitutive equation of CAAC can be expressed by piecewise expression, which can better reflect all the experimental characteristics. It was also found that CAAC has many similar characteristics with coral concrete and lightweight aggregate concrete. To improve the strength and toughness of CAAC, some fibers, such as organic fiber, can be added to expand the application of CAAC in engineering projects.

Performance of Zero Cement Concrete Synthesized from Fly Ash: A Critical Review

“…Subject focus [9,10,[19][20][21][22][11][12][13][14][15][16][17][18] Structural performance of ZCC [23, 24,33,[25][26][27][28][29][30][31][32] Mix design procedure [28,[34][35][36] Comprehensive review of the mixture design proportion and procedure [7,37,[46][47][48][49][38][39][40][41][42][43][44][45] Stress-strain characteristics [3,7,[54][55][56][57][58][59][60][61][62]…”

Enhancing the Microstructure and Sustainability of Ultra-High-Performance Concrete Using Ultrafine Calcium Carbonate and High-Volume Fly Ash under Different Curing Regimes

“…The research findings demonstrated the adverse effects of CFA on mortar workability and discouraged supporting its use in concrete manufacturing. In addition, Huailiang et al [32] investigated the stress-strain behavior of fly ash and slag alkali-activated concrete tested under uniaxial compression. Spontaneous failure of specimens was observed once they reached peak stress, which was more pronounced with the high-grade concrete mixes.…”

Use of Coal Bottom Ash and CaO-CaCl2-Activated GGBFS Binder in the Manufacturing of Artificial Fine Aggregates through Cold-Bonded Pelletization

“…Concrete is an artificial material that is widely used for building infrastructure in civil engineering [ 1 ] and it is estimated that around 30 billion tons of concrete are produced worldwide every year [ 2 ]. However, concrete production requires large quantities of natural fine and coarse aggregates, as about 70% of the total volume of concrete is composed these of aggregates.…”

“…Previous studies have suggested that bottom ash can be used as a mineral admixture for concrete after (1) grinding to increase its pozzolanic reactivity [8], (2) sieving to increase its fineness [9], (3) the addition of a superplasticizer to reduce its water absorption [10], or (4) putting it in a cement kiln as a raw material [11]. However, it is difficult to use raw bottom ash directly as a mineral admixture for concrete because its use generally decreases the workability of fresh concrete due to the angular grain texture [12] and bottom ash has a lower pozzolanic reactivity than fly ash due to its larger particle size [12].…”