### Title: Jet grouting: mathematical model to predict soilcrete column diameter - part I

Authors: Babak Nikbakhtan; Derek Apel; Kaveh Ahangari

Addresses: School of Mining and Petroleum Engineering, Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2R3, Canada ' School of Mining and Petroleum Engineering, Department of Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2R3, Canada ' Department of Mining Engineering, Islamic Azad University, Science & Research Branch, Tehran 1477893855, Iran

Abstract: Predicting soilcrete column diameter in jet grouting operations is one of the challenging tasks of engineers. By being able to determine the diameters, number of required columns and their spacing needed for activities such as cut off walls, soil improvement and slope stability activities can be calculated. However, there is no precise method to calculate and design the diameter before the operations. Therefore authors attempt to present a mathematical model using sum of squared-deviations (SSDs) method to estimate the diameter of soilcrete created by triple fluid jet grouting system. To do so, the actual data where soilcrete diameters have been measured, is used to prove and test the mathematical model. The effective jet grouting operational parameters that impact the diameter have been determined according to literature review of previous studies. On the basis of the results of modelling, the presented equation can predict soilcrete diameters with error range of 3-20%.

Keywords: jet grouting; sum of squared-deviations; SSD; soilcrete column diameter; mathematical modelling.

International Journal of Mining and Mineral Engineering, 2015 Vol.6 No.1, pp.46 - 56