Rockfall Hazard Rating System Adaptation Proposal for Urban Areas Through a Case Study in Mariana (MG, Brazil).
Larissa Regina Costa Silveira Silveira1; Laura Elisa Da Cunha Cunha1; Pedro Alameda Hernández Hernández1; Milene Sabino Lana Lana1; Tatiana Barreto dos Santos Santos1
1 Universidade Federal de Ouro Preto
Resumo
This work presents an adaptation of Rockfall Hazard Rating System (RHRS) for urban areas as a response to the need of analyzing the hazard in Cabanas district in the town of Mariana (MG, Brazil). Thus, a new easy-to-use classification system for rock falls in urban areas is proposed, furthermore some useful recommendations are offered when studying rock fall hazard through classification systems. As a direct consequence of this work, a deep analysis of the rock fall risk in a highly susceptible urban area is offered. Cabanas district is sited in the town of Mariana, belonging to the state of Minas Gerais (Brazil). It has an estimated population of 15000 inhabitants and it has been growing in extension and population within the past ten years without a real control from the authorities and consequently without a geological hazard analysis. As a consequence of this lack of urban planning, the current district boundary surrounds on the southeast side a high and stepped rock outcrop showing abundant fallen blocks. RHRS is a quick and uncomplicated method for assessment of rock fall hazard. However, it focuses roads exclusively; it encompasses not only geomechanical parameters but also traffic information. Thus, it is not to be applied in urban areas, our field of concern in this study. Hence, this work shows a rational adaptation of those traffic parameters and an examination of the rest of them. Furthermore, a review of the previous amendments offered for RHRS is shown and some of them applied, specially the substitution of the original geological characterization with the Slope Mass Rating classification system (SMR) value and the use of continuous functions to avoid the original discrete method for assessing the classification system parameter values. This work consisted of two stages, first field work and a latter analysis in office. In field, data acquisition was performed by hand, thus, points were selected according to their accessibility. The required parameters for the SMR calculation were evaluated, as w
Palavras-chave: Hazard Rating System; Rock Rating System; urban areas