Assessment of Compressive Strength Variations of Concrete Poured in-Site of Residential Buildings in Isoko District, Delta State, Nigeria

Abstract

Concrete with appreciable compressive strength is required for building constructions, to minimize the occurrence of building failures. Determination of the compressive strength of in-situ concrete produced in Isoko region of Nigeria was carried in this study. Concrete used for the construction of foundation wall footings for twenty residential buildings were sampled in the study. The compressive strength of the in-situ concrete was determined in accordance with ASTM standards. Field survey depicted that most (60%) of the concrete quality production process fell below the approved standard of 17 MPa, for residential buildings. The findings of the study revealed that the compressive strength of the in-situ concrete varied between 8.1 MPa and 19.8 MPa. Furthermore, the result of the compressive strength test showed that most (70%) of the in-situ concrete failed to meet the NIS recommended standard. Also, it was observed from the findings that proportionally, the concrete produced by conventional building/construction engineers was of a higher compressive strength, when compared to the concrete produced solely by masons. Based on observations obtained result obtained from this study, it is recommended that the Government should constantly educate building sites managers, on the need to adhere strictly to standard recommendations, in order to improve the quality of in-situ concretes produced.

Study on Dielectric Properties of Rice Husk Ash Stabilized Soil

“…The virgin soil sample employed for this study was collected from an active borrow pit site (1.5-2 m depth) in Oleh community of Delta State, southern Nigeria. Borrow pit soils are commonly used for civil engineering works in Nigeria, as they are considered to be lateritic soil with applicable engineering properties (Uguru et al, 2022). The soil was dried in the laboratory under natural environmental conditions (30±5 o C and 81±7% relative humidity).…”

Assessment of the geotechnical properties and suitability of borrow pit soil for construction works in some Niger Delta communities in Nigeria

“…Therefore, adequate information on the geotechnical properties used for these civil engineering construction works is inevitable, as this will minimize the occurrences of structural failures. Approximately five thousand (5,000) buildings had failed in Nigeria within the past ten years (Uguru et al, 2022).…”

Effect of Green Admixtures on the Mechanical Properties of Concrete Composite

“…The sand was air-dried in the laboratory for two weeks to reduce its moisture content. Uguru et al (2022) stated that soil moisture content has a tendency to interfere with concrete's mechanical properties, as very high soil moisture content tends to lower concrete compressive strength.…”

“…Each layer was rammed with a ramming rod (16 mm diameter mild steel rod) for 35 times. Then the cast concrete cubes were covered with a plastic sheet in a shady environment, to reduce the environment, delay setting time, and enhance the complete reaction of the cement with the water (Omoniyi et al, 2020;Uguru et al, 2022). Six groups of concrete were produced based on the experimental design.…”

“…Particle size grading was carried out on the fine aggregates to determine their suitability for concrete production. The ASTM C136 (2006) recommended procedures, as described by Uguru et al (2022), were adopted for the PSD. During the PSD, 500 g of dried sand was weighed with a digital weighing balance and poured into a pre-arranged sieve set.…”