Geotechnical aspects of bounce index of cricket pitch

Abstract

Good bounce on a cricket pitch is one of the most desire properties of pitch in world cricket. In Indian subcontinent generally pitches are low bouncy and do not provide good contest between bat and ball. The study was carried out to correlate the bounce index with different geotechnical properties of pitch soils especially with the stiffness of pitch. To serve this purpose, bounce meter and pin-point penetrometer were designed and fabricated. Total fifteen miniature pitches were prepared with different top layer compositions (five different combinations of 2:1 clay and fine sand) where, vertical layers were constructed with proper engineering judgments. Among these pitches one third was prepared with vegetation crack control system (grasses on the top of the pitches), one third was prepared with artificial crack control system (geotextile sheet provided 75 mm beneath the pitch surface) and remaining was kept without any crack control system. To protect the top soil of pitches from lateral infiltration and efflorescence plastic sheet was provided surrounding the top soil of pitches. After proper curing, the rebound height on the pitches was measured by bounce meter for different height of free fall. The stiffness of the pitches was measured by pin-point penetrometer. In addition, other properties of pitch soils such as, crack width, moisture content and field density were also measured. The correlations were established between the bounce index and other properties of pitch soils for different crack control systems. It was found that, from bounce and stiffness point of view, vegetation and no crack control system performed consistently with linear relations between parameters like clay content, crack width, moisture content, soil stiffness and bounce index, whereas, for artificial crack control system bounce index and the stiffness initially was found to decrease and beyond a certain (approximately 60%) clay content both stiffness and bounce index was found to increase. Regarding crack width control, artificial crack control system followed the similar linear pattern of other two control system. All these relations are proposed in terms of equations with good correlation coefficients.