Effect of Polypropylene Fibres on Torsional Strength of Ferrocement

Objectives: This paper presents a study on effect of adding Polypropylene (PP) fibres on torsional strength of ferrocement. Method: The main investigation was based on experimental works on torsional strength of ferrocement. In this study, the different percentage of PP fibres was added into the ferrocement mortar. The amount of PP fibre was added from 0%, 0.3%, 0.6% and 0.9%. A torsion test rig was developed specifically for this study to ensure torsional force applied equally at both end of the test specimens. Finding: It is determined that 67.2% of the torsional strength variation of the ferrocement was influenced by PP fibres. In comparison to the normal ferrocement without additional PP fibres, there was torsional strength improvement about 38% contributed by PP fibres to the ferrocement specimens. The effects given by interaction of PP fibre and volume faction of the mesh on torsion were only 2.3%. The predictive applied torque equations were derived from this study. There is a good agreement between the predicted values of maximum applied torque to the observed value from the experiment where less of 5% different was observed. Application: From this study, it is concluded that by adding PP fibre to the ferrocement mortar the crack can be reduced and the PP fibres contribute to the torsional strength.