Design of reinforced block work storage tanks

Crack control in aqueous retaining concrete structures has been of a primary concern to us. The codes available such as CPIIC and DIN etc. have suggested different ways of doing it. However the codes have dealt mainly with reinforced concrete structures only and very little have been said about reinforced Masonry Structures. So far one can predict or calculate, with good precision, the size of a crack due to flexural tensile loading, but it has not been certain with loadings due to direct tensile forces. The study aims at establishing a design code for Reinforced Block-work Storage Tanks, using Serviceability limit state of cracking criteria. Here controlling a statistical approach of ascertaining the crack size due to direct tensile forces has been thought of. Models to simulate the conditions in a reinforced blockwork storage tank have been built. A testing device, to load the models safely and maintaining the required membrane state conditions, has been designed. An easy way of producing concrete blocks which can ready be manufactured in villages has been thought of. Different types of steel available in the country have been tested for their suitability in cracks. Reinforced Blockwork storage tanks are easy to construct and so they have been popular in Tanzania. Nevertheless their use has been limited to water storage tanks only. However their use can extend to the storage of grains in the country. Naturally different usage require different crack size limitations for the users to be satisfied. For example, water storage requires a different crack size limitation from that of rice or Beans storage tanks, although the containers from that of rice or Beans storage tanks, although the containers could be subjected to the same magnitude of loading. Basing on this study one may get inisight in the design of reinforced Blockwork storage tanks for different purposes.