FERROCEMENT CYLINDRICAL TANKS: CRACKING AND LEAKAGE BEHAVIOR.

Cylindrical ferrocement tanks were subjected to increasing internal water pressures to study the influence of the reinforcing parameters on their cracking and leakage behavior. It is found that cracking in the ferrocement shell occurs at an average tensile stress of about 500 psi and that the average crack width at a given tensile stress in the composite decreases with an increase in the volume fraction and/or the specific surface of reinforcement. It is also found that the composite stress at the onset of leakage increases with an increase in specific surface and, everything else being equal, that the leakage or loss of water increases with the stress in the steel mesh and decreases with the wall thickness. Based on the information generated, allowable tensile stresses of about 30,000 psi in the steel are recommended for the design of watertight ferrocement tanks.