Impact of Common Mistakes in Concrete Mixtures on the Mechanical Properties of Concrete

This study examines how common on-site construction errors affect the compressive strength and workability of concrete, focusing on conditions typical in low-to-middle income countries such as Libya. Through controlled experiments using 34 trial mixes, this research simulates implementation errors including excess water, improper aggregate proportions, and out-of-specification materials. Even single mistakes caused significant strength reductions, with water-related errors having the most pronounced impact. While multiple concurrent flaws often led to strength losses exceeding 60%, mixes with four or more errors did not consistently show further deterioration, suggesting a threshold beyond which performance degradation stabilizes. These findings emphasize the importance of early-stage quality control, particularly regarding water content and aggregate grading. The results also highlight that directly adopting design standards from developed countries may be inappropriate without adjustment, as differences in construction oversight and implementation quality can lead to substantial performance gaps if not properly accounted for.