In Situ Block Size Distribution Aimed at the Choice of the Design Block for Rockfall Barriers Design: A Case Study along Gardesana Road
When studying rockfall phenomena, a single value of the block volume is not sufficient to take into account the natural variability of the geometrical features (orientation, spacing, persistence) of the discontinuity sets. Different approaches for obtaining cumulative distributions of potentially de...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-06-01
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| Series: | Geosciences |
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| Online Access: | https://www.mdpi.com/2076-3263/10/6/223 |
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| author | Gessica Umili Sabrina Maria Rita Bonetto Pietro Mosca Federico Vagnon Anna Maria Ferrero |
| author_facet | Gessica Umili Sabrina Maria Rita Bonetto Pietro Mosca Federico Vagnon Anna Maria Ferrero |
| author_sort | Gessica Umili |
| collection | DOAJ |
| description | When studying rockfall phenomena, a single value of the block volume is not sufficient to take into account the natural variability of the geometrical features (orientation, spacing, persistence) of the discontinuity sets. Different approaches for obtaining cumulative distributions of potentially detachable block volumes are compared. A highly fractured rock mass outcropping along the western Lake Garda (Italy), consisting of prevailing limestone and interbedded marls, is studied in detail from geological and geostructural points of view. Then, a representative rock face has been selected and analyzed with traditional and non-contact survey methods to identify the main discontinuity sets and to collect spacing samples. Based on these data, in situ block size distributions for different combinations of sets are built following statistically-based approaches, without the use of a Discrete Fracture Network (DFN) generator. The validation of the obtained distributions is attempted based on the detached block surveyed at the foot of the slope. However, in this particular case study, the detached blocks cover only a minimal volume range compared to both theoretical values and visible rockfall scars. The fallen rock blocks have a marginal role in design block determination, since their volume depends on geological discontinuities (bedding and fractures) and could be affected by other processes after the detachment (e.g., fragmentation). The procedure here described should be standard practice in the study of rockfall events, and it should be uniform in European standards such as Eurocodes. Future developments should involve the scientific community for setting the percentiles of the probability distribution to be considered for block design definition. |
| first_indexed | 2024-03-10T19:19:04Z |
| format | Article |
| id | doaj.art-90fc52b58c7d4bb19279736c13120fd5 |
| institution | Directory Open Access Journal |
| issn | 2076-3263 |
| language | English |
| last_indexed | 2024-03-10T19:19:04Z |
| publishDate | 2020-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Geosciences |
| spelling | doaj.art-90fc52b58c7d4bb19279736c13120fd52023-11-20T03:07:48ZengMDPI AGGeosciences2076-32632020-06-0110622310.3390/geosciences10060223In Situ Block Size Distribution Aimed at the Choice of the Design Block for Rockfall Barriers Design: A Case Study along Gardesana RoadGessica Umili0Sabrina Maria Rita Bonetto1Pietro Mosca2Federico Vagnon3Anna Maria Ferrero4Department of Earth Sciences, Università degli Studi di Torino, via Valperga Caluso 35, 10125 Torino, ItalyDepartment of Earth Sciences, Università degli Studi di Torino, via Valperga Caluso 35, 10125 Torino, ItalyInstitute of Geosciences and Earth Resources—CNR, via Valperga Caluso 35, 10125 Torino, ItalyDepartment of Earth Sciences, Università degli Studi di Torino, via Valperga Caluso 35, 10125 Torino, ItalyDepartment of Earth Sciences, Università degli Studi di Torino, via Valperga Caluso 35, 10125 Torino, ItalyWhen studying rockfall phenomena, a single value of the block volume is not sufficient to take into account the natural variability of the geometrical features (orientation, spacing, persistence) of the discontinuity sets. Different approaches for obtaining cumulative distributions of potentially detachable block volumes are compared. A highly fractured rock mass outcropping along the western Lake Garda (Italy), consisting of prevailing limestone and interbedded marls, is studied in detail from geological and geostructural points of view. Then, a representative rock face has been selected and analyzed with traditional and non-contact survey methods to identify the main discontinuity sets and to collect spacing samples. Based on these data, in situ block size distributions for different combinations of sets are built following statistically-based approaches, without the use of a Discrete Fracture Network (DFN) generator. The validation of the obtained distributions is attempted based on the detached block surveyed at the foot of the slope. However, in this particular case study, the detached blocks cover only a minimal volume range compared to both theoretical values and visible rockfall scars. The fallen rock blocks have a marginal role in design block determination, since their volume depends on geological discontinuities (bedding and fractures) and could be affected by other processes after the detachment (e.g., fragmentation). The procedure here described should be standard practice in the study of rockfall events, and it should be uniform in European standards such as Eurocodes. Future developments should involve the scientific community for setting the percentiles of the probability distribution to be considered for block design definition.https://www.mdpi.com/2076-3263/10/6/223rockfallspacingblock volumeIBSDLake Garda |
| spellingShingle | Gessica Umili Sabrina Maria Rita Bonetto Pietro Mosca Federico Vagnon Anna Maria Ferrero In Situ Block Size Distribution Aimed at the Choice of the Design Block for Rockfall Barriers Design: A Case Study along Gardesana Road Geosciences rockfall spacing block volume IBSD Lake Garda |
| title | In Situ Block Size Distribution Aimed at the Choice of the Design Block for Rockfall Barriers Design: A Case Study along Gardesana Road |
| title_full | In Situ Block Size Distribution Aimed at the Choice of the Design Block for Rockfall Barriers Design: A Case Study along Gardesana Road |
| title_fullStr | In Situ Block Size Distribution Aimed at the Choice of the Design Block for Rockfall Barriers Design: A Case Study along Gardesana Road |
| title_full_unstemmed | In Situ Block Size Distribution Aimed at the Choice of the Design Block for Rockfall Barriers Design: A Case Study along Gardesana Road |
| title_short | In Situ Block Size Distribution Aimed at the Choice of the Design Block for Rockfall Barriers Design: A Case Study along Gardesana Road |
| title_sort | in situ block size distribution aimed at the choice of the design block for rockfall barriers design a case study along gardesana road |
| topic | rockfall spacing block volume IBSD Lake Garda |
| url | https://www.mdpi.com/2076-3263/10/6/223 |
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