Browsing by Author "Niiranen, Tea"

The purpose of rock mass classification is to get to know the major features affecting the rock and to divide the rock mass in to parts that behave the same way. RG-classification is a Finnish qualitative rock mass classification that describes the rock mass objectively. Another commonly used classification is Q-system, which gives numerical values for the classified rock. ISO (the International Organization for Standardization) is a worldwide federation of national standard bodies, which has published a standard ISO 14689-1 for identification and classification of rock for ground- and water construction. The Finnish Standards Association SFS has approved the aforesaid for international standard SFS-EN ISO 14689-1. In this thesis I use the name ISO-classification for identification and classification of rock according to this standard. The purpose of the study is to compare the ISO-classification system to the rock classification systems used in Finland, especially to the commonly used RG- and Q-classifications. The main focus of this study is the Tampere Rantatunneli where Q- and RG-classification systems are systematically used. The ISO-classification is divided in to three parts: the identification of the rock and the descriptions of rock material and rock mass. To help the testing of classification a mapping form has been developed to take the parameters above into account. Q-parameters have also been considered in the form and the possibility of exploiting the ISO-parameters in defining the Q-system was also tested. The mapping according to the ISO-classification was performed in five different tunnel breaks in Tampere Rantatunneli. These mapping areas A, B, C, D and E are located in Näsinkallio and Naistenlahti areas. Three main joint directions were found in each five tunnel breaks with one of them parallel to schistosity. The main rock type in each tunnel break was micagneiss classified as very hard (100-250 MPa). RG- and ISO-classifications are both descriptive methods that describe the rock and do not provide a quantitative result of the rock quality. However, the ISO-classification is more precise than the RG-classification. Using the ISO-classification in Finland requires that some of the measuring parameters are either partly or totally modified or that categories are combined together. It is possible to derive parameters from ISO-classification to be used as Q-classification parameters.