Jointing Sand Characteristics of Interlocking Concrete Block Pavements at Different Slopes and Joint Widths

This study was conducted to investigate the performance of jointing sand of interlocking concrete block pavement using different slopes and joint widths. A laboratory scale model of 1.2x0.6 (m(2)) was built and concrete blocks (quadpave) of 200x100x60 (mm(3)) were used as a surface layer. The width of the joint between concrete blocks used for testing varies from 2, 4 and 6 mm, with slopes of 0, 5, 10 and 15%. Pull out test was performed for each condition. The results show that the 2 mm joint width was found suitable to be used on the steep road. It is shown that the interlocking behaviour of concrete blocks decreases when the slope is increased. The forces needed to dislodge concrete blocks from its place become smaller as the joint width gets larger. The presence of small amount of water helps the jointing sand compressed but greater amount of it will cause erosion particularly at steeper slope. It is suggested to use the maximum slope of 10% for interlocking concrete block pavement to avoid sand erosion from the joints and subsequently decrease the interlock behaviour between concrete blocks.