Use and Misuse of Rock Mass Classification Systems with Particular Reference to the QSystem 4 Table 1. Main developments of the Qsystem Year Development Author(s) and title of paper 1974 The Qsystem is introduced Barton, Lien, and Lunde: Engineering classification of rock masses for the design of tunnel support. Grimstad and BartonUpdating the Qsystem for NMT. Fagernes, Norway: 1993.
Barton, N. Tunnel sikring ved NMT basert p borkjernelogging. Bergmekanikkdag, Oslo: 1994. Barton and GrimstadRock mass conditions dictate Q system tunnel design between NMT and NATM. TTI, London: 1994. Barton and GrimstadThe Qsystem following twenty years application Apr 11, 2011 tunnel support design using empirical methods The development of empirical support design methods for the stability of underground project aim to include the experience gained from similar projects, in similar circumstances, in its construction.
A comparison is made between the tunnel support design based on the classical Teraghi rcak load method and the support selection based on the RSR Concept, the Geomechanic Classification.
and the QSystem. Short on the Qsystem. The Qsystem for rock mass classification, developed at the Norwegian Geotechnical Institute (NGI) in 1974, originally included a little more than 200 tunnel case histories, mainly from Scandinavia (Barton et al.1974). In 1993 the system was updated to include more than 1000 cases (Grimstad and Barton, 1993). Publications on hard rock tunnel support design in the South confirm its applicability, the QIndex is applied to two tunnels in different geotechnical conditions.
The first case study covers a tunnel, which has stood virtually system based on the Q Most of the tunnel is in sandstone with a Q value of about 40. Adopting an ESR value of 0. 8, the Qsystem [15 indicates support should comprise 6. 5m bolts at about 2. 6m ith centres w 40mm reinforced shotcrete. The Qsystem of rock mass classification and support design is based on a numerical assessment of the rock mass quality using six different parameters.
The six parameters consist of the RQD, the number of joint sets, the roughness of the most unfavourable joint sets, the roughness of the most For the linguistics formalism, see Qsystems. For the genetic method, see Qsystem (genetics). The Qsystem for rock mass classification is developed by