Quality control of concrete constructions in Tanzania: assessment of extent and objectivity

In construction projects, quality control should be undertaken continuously. In order to meet the specified quality requirements, there must be proper planning on who will do it, how it will be done, the materials, tools and equipment to be used, and the delivery time of the product. Then the product has to be assessed to ensure that it conforms to the established quality standard. If the product deviates from the quality requirements, corrective measures should be taken. Quality control should be applied to all activities at all levels of the process; from the cleaner to the president of the organisation. Each person concerned with the production process is responsible for producing products which meet the quality requirements. For concrete construction projects, the project team involved include the promoter, consultants (architects and engineers), the contractors and ingredient materials producers. The materials in question are cement, aggregates and steel reinforcement. From the previous studies on quality control of concrete constructions in Tanzania, it was established that there are deficiencies in implementing quality control and that the concerned parties seem not to care much about it. In this thesis, a study on the extent and objectivity of quality control prevailing in the concrete construction projects in Tanzania has been carried out. The study was done by interviews, data collection on control tests of ingredient materials as well as the concrete matrix, and by performing control tests on cement, aggregates, reinforcing steel and the concrete matrix. The study covers a sample of consultants, contractors, and ingredient materials producers. The results obtained show that the extent and objectivity of implementing quality control are both very unsatisfactory. Hence, it is recommended that the parties involved with the construction projects should be made aware of the importance of quality control and encouraged to strive to produce quality products.