A Study on Gel/Space Ratio Development in Binary Mixture Containing Portland Cement and Meta-Illite Calcined Clay/Rice Husk Ash.

Supplementary cementitious materials (SCMs) have been widely used to enhance both the microscopic and macroscopic properties of the Portland cement (PC)-SCM composite matrix. Few studies have been undertaken to establish the gel/space ratio of meta-illite calcined clay (MCC) and rice husk ash (RHA)-based high-performance concrete (HPC) mortar. This experimental paper describes a conventional degree of hydration (non-evaporable water) and porosity routes of establishing a link amid the gel/space ratio and compressive strength of a sieved mortar from Class 1 (50-75 MPa) HPC at an early age. Using the non-evaporable water method, this paper predicted the gel/space ratio of the hardened MCC/RHA-based HPC mortars and curved fitted into Powers' exponent equation. The results from this study revealed that MCC or RHA additions (5-30% by weight of PC) to the PC-SCM matrix led to a moderate decline in the compressive strength of the low water-binder ratio (W/B) HPC mortar. The modification aimed at void volume (superabsorbent polymers, SAP, and air) applying Bolomey's formula and Powers' gel/space ratio developed a suitable fitting into the Powers' model. This experimental procedure shows feasibility to predict the MCC and RHA outcome on the compressive strength of HPC.

Data exploration on factors that influences construction cost and time performance on construction project sites.

This data article explores the factors that contribute to maintaining steady cost projection on construction projects. The data was obtained using structured questionnaire designed in Likert scale. The responses were solicited from category of construction practitioners. Simple random sampling was employed in the distribution of the questionnaires to the respondents. Data samples were analysed using severity index, ranking and simple percentages. The analysis of the data brought to fore some important data on factors that causes cost overrun, they include: contractor's inexperience, inadequate planning, inflation, incessant variation order, and change in project design. They are critical to causing cost overrun, while project complexity, shortening of project period and fraudulent practices are found to be responsible. The data fall within the percentages of possible consequences of cost overrun when compared with those available in scientific literature. The data can provide insights on how to mitigate the risks of project deviation from initial cost and as-built project.

Data on mixing and curing methods effects on the compressive strength of concrete.

Curing, though important is sometimes underrated in concrete production. This dataset provided shows the effects of four (4) different methods of curing on two distinct mix ratios. The data provided in this article are for a study that was conducted on one hundred and sixty (160) cube samples of mix ratios 1:2:4 and 1:1.5:3 while employing four (4) different methods of curing. The data given in the article displays the finding of the study. The findings can aid in prediction and optimization of concrete behavior and compressive strength when any of the curing methods are utilized.

Data on the pozzolanic activity in coconut shell ash (CSA) for use in sustainable construction.

The data presented herein are results of the research summary of the investigation for pozzolanic activity in coconut shell ash (CSA) towards a sustainable construction. The data article provides information on the properties of Coconut Shell Ash that are indicative of pozzolanic activity as stated in ASTM C618-15 (2015) [1], BS EN 197-1 (2011) [2] and Joshua et al. (2018) [3]. The data are the physical property of the sand used in determining the binder strengths and the chemical and physical properties (oxide composition and Strength Activity Indices respectively) of the pulverized, calcined and sieved Coconut Shell Ash.