Premature deterioration of our nation’s concrete structures has been a persistent and frustrating problem to those responsible for maintaining them as well as to the public. One of the ways to minimize these problems is to make the concrete less permeable by densifying the cementitious paste. This densification is achieved by using a lower water-cement ratio and supplementary cementitious materials (SCMs). Many researchers have successfully provided a rundown of the current facts about the favorable use of supplementary cementitious materials. These summaries contain a limited number of SCMs considered. This paper reviews the influence of twelve (12) selected supplementary cementitious materials, which are; Cupola Furnace Slag Powder (CFSP), Blast Furnace Slag Powder (BFSP), Silica Fume (SF), Fly Ash (FA), Rice Husk Ash (RHA), Metakaolin (MK), Coconut Husk Ash (CHA), Palm Oil Fuel Ash (POFA), Wood Waste Ash (WWA), Sugar Cane Bagasse Ash (SCBA), Corn Cob Ash (CCA), Bamboo Leaf Ash (BLA), workability and compressive strength of concrete, thus providing a larger database of the current facts about the favorable use of industrial and agricultural byproducts in the concrete industry. Review of literature and careful observation of results were used in generating the useful information provided in this paper. This review considered the compressive strength and workability of concrete containing partial substitute of ordinary Portland cement by the aforementioned supplementary cementitious materials. The chemical compositions of each of these selected supplementary cementitious materials were also reported. This study revealed that the incorporation of these twelve SCMs significantly improves the strength and workability of concrete. It is therefore recommended that arrangements be made by those interested in this paper for processing of these SCMs into commercial cement rather than being disposed of as wastes.

Fire outbreaks in buildings have been a major concern in the world today. The integrity of concrete is usually questioned due to the fact that after these fire outbreaks the strength of the concrete is reduced considerably. Various methods have been adopted to improve the fire resistance property of concrete. This study focused on the use of coconut fibre to achieve this feat. In this study, varying percentages of treated and untreated coconut fibres were incorporated into concrete and the compressive strength was tested for both before heating and after heating. The percentages of replacement were 0.25, 0.5, 0.75 and 1% fibre content by weight of cement. Concrete cubes that had 0% fibre served as control specimens. After subjecting these concrete cubes to 250 °C and 150 °C for a period of 2 h, the compressive strength increased when compared to the control. The compressive strength increased up to 0.5% replacement by 3.88%. Beyond 0.5% fibre, the compressive strength reduced. Concrete having coconut fibre that had been treated with water also exhibited the highest compressive strength of 28.71 N/mm². It is concluded that coconut fibres are a great material in improving the strength of concrete, even after it was exposed to a certain degree of elevated temperature.

Strength failure persists both in structural and mechanical analysis. One of its prominent characteristics is the adequate provision for parameters that minimise or maximise strength objectives while satisfying boundary conditions. The previous optimisation of concrete strength usually neglects mix design mechanisms induced by optimisation. Recent efforts to accurately optimise the concrete compressive strength have factored in some of these mechanisms. However, optimising concrete strength modified with high silica and alumina precursors, and crucial mix design factors are rare. Consequently, this paper optimised the concrete workability and strength, incorporating binding, water/binder ratio, binder/aggregate ratio, and curing mechanisms using the Box–Behnken design approach (BBDA). A waste material, anacardium occidentale (cashew) nutshell ash, was valorised and used at 5, 10, and 15 wt.% of cement. The composites were made, cured and tested at 14–90 d. The results revealed a high precision between the experimental slump and the optimisation slump at 97% R². In addition, a 5% increase in compressive strength was obtained compared with the target compressive strength. Besides, the correlation between the model equation obtained from this study and predictions of previous studies via BBDA yielded a strong relationship.

Indiscriminate waste disposal poses a severe environmental challenge globally. Recycling of industrial wastes for concrete production is currently the utmost effective way of managing wastes for a cleaner environment and sustainable products. This study investigates the strength characteristics of self-compacting concrete (SCC) containing induction furnace slag (IFS) as a supplementary cementitious material (SCM). The materials utilized include 42.5R Portland cement, induction furnace slag as an SCM ranging from 0 to 50 % by cement weight at 10 % interval, river sand, granite, water and superplasticizer. The fresh properties were tested for filling ability, passing ability and segregation resistance, the strength characteristics measured include compressive strength, splitting tensile strength, flexural strength and Schmidt/rebound number. The oxide compositions and microstructural analysis of SCC were investigated using x-ray fluorescence analyser (XRF) and scanning electron microscopy equipped with energy-dispersive x-ray spectroscopy (SEM-EDS), respectively. Empirical correlations were statistically analyzed using MS-Excel tool. The filling ability characteristic was determined via both the slump flow test and the T _50cm slump flow time test. Moreover, the passing ability characteristic was determined using L-Box test. The segregation resistance characteristic was determined using V-funnel at T _5minutes test. The results of the fresh properties showed a reduction in the slump flow with increasing IFS content. On the other hand, the T _50cm slump flow increased with increasing IFS content. Furthermore, the L-Box decreased with higher IFS content. On the contrary, the V-funnel at T _5minutes increased considerably with greater IFS content. The strength test results revealed that the strength properties increased to 20 % IFS, with a value of 66.79 N/mm ² compressive strength at 56 days, giving a rise of 12.61 % over the control. The SCC microstructural examinations revealed the amorphous and better interface structures with increasing IFS content in the mix. The empirical correlations revealed that linear relationships exist among the measured responses (fresh and strength properties). Ultimately, IFS could be utilized as a sustainable material in producing self-compacting concrete.

This study led to the creation of empirical models of the properties of high-performance self-compacting concrete (HPSCC) with inductionfurnace slag (IFS) added as an extra cementitious ingredient. The ingredients were Portland cement, IFS ranging from 0 to 50% by cement weight, granite, river sand, water, and superplasticizer. Using a slump flow test, the filling-ability property of the newly produced HPSCC was investigated. Similarly, a compressive strength test was used to determine the hardened HPSCC's compressive strength. Using already established scientific ideas, the empirical model of the filling-ability characteristic of the fresh HPSCC was generated, on the basis of the slump flow and the volume of the paste of the fresh concrete. Likewise, the empirical model of the compressive strength of the hardened HPSCC was generated, based on the combination of the parameters of the strength developed over time, with the strength developed, due to the addition of the IFS. Based on these, the empirical model of the fillingability property of the fresh HPSCC was ρ r s f 2 = 0.002 ( 1 - V P ) - 11.34 {{{\rho _r}} \over {{s_f}^2}} = 0.002{\left( {1 - {V_P}} \right)^{ - 11.34}} , while that of the compressive strength of the hardened HPSCC was f c ( t ) = t 4.52 + 0.78 t ( − 0.0109 ( P i f s ) 2 + 0.2632 P i f s + 52.446 ) {f_c}\left( t \right) = {t \over {4.52 + 0.78t}}\left( { - 0.0109{{\left( {{P_{ifs}}} \right)}^2} + 0.2632{P_{ifs}} + 52.446} \right) . The empirical models were then validated using test data from this work. Strong links between the measured and the predicted values were identified by the empirical correlations, where the coefficient of determination (R ² ) value for the filling ability property, gave above 94% and the R ² value for the compressive strength, gave above 86%. The estimated slump flow and the compressive strength were approximately equal to the experimental values. The outcomes demonstrated that IFS may be utilized to produce an eco-friendly and environmentally sustainable HPSCC. The models can be adopted in designing HPSCC containing IFS as a supplementary cementitious material (SCM) and in predicting its filling-ability and compressive strength, which will benefit the construction industry.

Induction furnace slag (IFS) and quarry dust (QD) were reported as good materials in making ordinary concrete. Studies were not done on utilizing IFS and QD as constituents of high-performance-self-compacting-concrete (HPSCC). This study aims at assessing the effects of induction furnace slag and quarry dust on the strength and durability of high-performance self-compacting concrete. Strength tests including compressive, flexural, split tensile, rebound hammer tests were conducted on HPSCC. Likewise, durability tests including water absorption, total porosity and electrical resistivity tests were conducted. IFS at 0 % to 50 % (at 10 % intervals) replacement with Portland cement was used. Also, the optimum IFS content was combined with QD at 0 % to 50 % (at 10 % intervals) replacement with river sand. The results revealed an increment in strength up to 20 % IFS, 50 % QD with a rise of 15.34 % compressive strength over the control. The durability improved up to 20 % IFS, 60 % QD with a rise of 16.86 % electrical resistivity over the control. These showed that IFS and QD can be used for the production of HPSCC.