Standard method of measurement for underground development works

Abstract

PURPOSE : Bills of quantities for underground development works (UDW) are presently prepared with no uniformity of practice, leading to troublesome misinterpretations and inconsistent pricing by contractors. This article describes the results of research to determine if there is a requirement from the underground development industry to develop a separate standard system of measurement. METHODOLOGY : Firstly, an empirical study was conducted, with existing bills of quantities reviewed by way of methodological analysis and, secondly, market opinion was tested through purposive sampling to obtain responses from a relatively small population of experienced underground development professionals. FINDINGS : The results showed that UDW bills of quantities are not standardised and that there is a need to develop a bespoke standard system of measurement. UDW differs from civil works, and therefore the nature of the work, the circumstances under which it will be executed (site conditions) and the materials to be used have to be described in the bills of quantities in order to make tender comparisons easier. LIMITATIONS : Only underground development unit operations (drilling, blasting, supporting, loading and hauling activities) were studied, with brief references to auxiliary operations. The influence of contractual strategies and contract types was excluded. VALUE : Motivation is provided for developing a commonly accepted standard system of measurement (and associated model bills of quantities) to suit the needs of the UDW industry. Such a modified method of measurement should work in harmony with existing building, civil or other recognised measurement systems.