Horizontal directional drilling pilot bore simulation

Abstract

Various underground communications (water or gas supply systems, sewage, power lines) have been installed in recent years using trenchless technologies, i.e. horizontal directional drilling (HDD). This technique by its nature does not disturb the traffic and is environmentally friendly. One must be aware that, with HDD, pipeline building time is shortened. With respect to the above, HDD is especially effective in highly populated or industrial areas. However, it is necessary to ensure that HDD works, in order to prevent damage to installed underground facilities. The aim of this work is to propose a user-friendly and inexpensive simulation tool with required functionality for HDD trajectory-planning under field conditions. The optimization of HDD trajectory-planning consisted of analyzing the methods for pilot bore trajectory construction: step-by-step, six-point, and four-point control. The statistical evaluation of such methods revealed their similarity regarding time resources (when using any of the methods mentioned above, the upper limit of 95% confidence interval of HDD trajectory-planning duration does not exceed 1 min). The tests of the simulation tool at work places with Ditch Witch JT922 demonstrated good functionality due to its intuitive interface and simple and fast ability to replan a HDD trajectory. Increased accuracy of bore path planning and simpler pilot bore construction were achieved.