Proper Mixing of C25 Concrete and Strength Test

The purpose of this bachelor’s thesis was to highlight the needs of caution during concrete mix to overcome all possible disputes and failures in concrete mixing. The project aimed at delivering important steps necessary to be taken during and after concrete mixing process to achieve quality concrete. To set up the background for the study, a literature review on concrete, cement, aggregates, admixtures, a trial mix was carried out. This review highlighted the importance of proper mix design, concrete element properties, concrete properties, the influence of ad-mixtures on concrete and the importance of compressive strength test. Three different trials mix for C25 concrete grade were carried out in concrete lab. The amount of water in the trials was fixed as well as same aggregates were used for all three trials. The major component of concrete i.e. cement, aggregates were tested before the trials mix. After the concrete mix the specimens were tested on 7th and 28th day to find out the compressive strength of concrete mix. Three different strength of C25 concrete were achieved as a result of trials. One trials failed to meet the Mean targeted strength of C25 concrete whereas two trials achieved Mean targeted strength. The failure in one trial shows that even following proper caution there might still be some factor that might affect the concrete strength. Therefore it shows the importance of proper concrete mix. From three different results received, the graph was obtained which shows the correlation between compressive strength and water/cement ratio. This graph can be used to predict the strength of C25 concrete in different water/cement ratio. The thesis can be also used as a proper guideline for any concrete mixes as the thesis has summarized the importance of different test and steps to be taken before and after the concrete mix