The research presented in this thesis results from efforts to evaluate current design methodologies for safety benches in surface aggregate quarries. Proper bench design is important for preventing rockfall related accidents and injuries without wasting the reserves held in the benches. An in depth analysis has been performed using the results from 230 rockfall tests conducted at two surface quarries. The goal of this project is to give practitioners the tools they need for improved bench design. Principal Components and Cluster Analysis, techniques not previously applied to rockfall investigations, have been performed on the test data. The results indicate that both are valid analytical methods which show that the factors affecting the rollout distance of a rock are wall configuration, rock dimensions, and rock energy. The test results were then compared to the Ritchie Criteria, Modified Ritchie Criterion, Ryan and Pryor Criterion, Oregon Department of Transportation design charts, and RocFall computer simulations. Analysis shows that the lognormal distribution curves fitted to the test data provide an excellent yet quick design reference. The recommended design method is computer simulation using RocFall because of the ease of simulation and the site specific nature of the program. For the two quarries studied, RocFall analysis showed that 20 ft benches with a 4 ft berm will hold over 95% of rockfalls, a design supported by the field testing. Conducting site-specific rockfall testing is also recommended to obtain realistic input parameters for the simulations and to provide design justification to regulatory agencies. / Master of Science

[pt] Esta tese insere-se no contexto de diversos trabalhos realizados pelo grupo de estudo de Movimentos de Massas formado pelas Instituições PUC-Rio e COPPE-UFRJ, liderado pelos Professores Alberto Sayão e Anna Laura Nunes. O trabalho busca abordar formas de se obter as forças de impacto de fluxos de detritos brasileiros, principalmente advindas da parcela referente aos blocos de rocha (parcela não viscosa) do movimento. O tema ainda necessita de metodologias bem definidas e aplicáveis a casos que, recentemente, apresentam-se como objeto de estudo pelas comunidades técnicas e acadêmicas, no esforço de se mitigar e/ou conviver com movimentos de massa, cada vez mais presentes nas cidades brasileiras. Assim, propõe-se uma metodologia que utiliza ferramentas numéricas como o DAN-3D e o ROCFALL para se obter as forças de impacto dos blocos rochosos em estruturas de contenção estáticas e dinâmicas, levando em consideração parcelas viscosas e forças de atrito, bem como, compara-se a metodologia proposta com as métodos empíricos já existentes. Para obtenção dos resultados buscou-se a aplicação da metodologia em três casos recentes, de importantes fluxos de detritos ocorridos no Brasil, situados na Serra do Mar, mais precisamente nos municípios de Nova Friburgo e Teresópolis no Rio de Janeiro e em São Sebastião em São Paulo. / [en] This thesis is part of the context of several works carried out by the study group of Mass Movements formed by the Institutions PUC-Rio and COPPE-UFRJ, led by Professors Alberto Sayão and Anna Laura Nunes. The work seeks to address ways of obtaining the impact forces of Brazilian debris flows, mainly arising from the portion referring to the rock blocks (non-viscous portion) of the movement. The subject still needs well-defined methodologies applicable to cases that, recently, have become an object of study by the technical and academic communities, in an effort to mitigate and/or coexist with mass movements, increasingly present in Brazilian cities. Thus, a methodology is proposed that uses numerical tools such as DAN-3D and ROCFALL to obtain the impact forces of rock blocks in static and dynamic containment structures, taking into account viscous portions and frictional forces, as well as the proposed methodology is compared with existing empirical methods. To obtain the results, we sought to apply the methodology in three recent cases of important debris flows that occurred in Brazil, located in the Serra do Mar, more precisely in the municipalities of Nova Friburgo and Teresópolis in Rio de Janeiro and in São Sebastião in São Paulo.

Στην παρούσα εργασία γίνεται προσπάθεια εφαρμογής και βελτιστοποίησης υπολογιστικών μεθόδων ως προς την προσομοίωση καταπτώσεων βραχωδών τεμαχών από πρανή, για τον ασφαλή σχεδιασμό μέτρων πρόληψης και προστασίας. Με χρήση του λογισμικού Rocfall της Rocscience, έγιναν προσομοιώσεις σε καταπτώσεις βράχων που εντοπίστηκαν στους οικισμούς της Πλατιάνας του Δήμου Σκιλλούντος Ηλείας και Μύλοι του δήμου Ανδριτσαίνης Ηλείας. Επίσης συντάχτηκε αλγόριθμος υπολογισμού πολλαπλών συντεταγμένων, ώστε να προβληθούν τα αποτελέσματα σε χάρτες χωρικής κατανομής. / This dissertation is an attempt of application and optimization of numerical analysis methods of Rockfalls, for a safe design of remedial measures. With the use of program Rocfall of Rocscience, simulations were made at the settlements of Platiana, prefecture of Hlia, Miloi, prefecture of Hlia and Kimi, prefecture of Evia. Furthermore an algorithm (coordinates calculator) was made in order to be able after the simulation to plot the results as spatial distribution maps.