Landslide Occurances at Maierato, Italy. an Engineering Geological View
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University of Pennsylvania ScholarlyCommons Master of Science in Applied Geosciences Department of Earth and Environmental Project Designs Science 8-1-2010 Landslide Occurances at Maierato, Italy. An Engineering Geological View Jaithish John University of Pennsylvania Follow this and additional works at: https://repository.upenn.edu/msag_projects Part of the Earth Sciences Commons John, Jaithish, "Landslide Occurances at Maierato, Italy. An Engineering Geological View" (2010). Master of Science in Applied Geosciences Project Designs. 2. https://repository.upenn.edu/msag_projects/2 A Project design submitted to the Graduate Faculty of The University of Pennsylvania partial fulfillment of the Requirements for the Degree of Master of Science in Applied Geosciences Summer 2010. This paper is posted at ScholarlyCommons. https://repository.upenn.edu/msag_projects/2 For more information, please contact [email protected]. Landslide Occurances at Maierato, Italy. An Engineering Geological View Abstract This paper focuses on the 15th February, 2010 Maierato landslide in the Calabria region of Italy. The slide is believed to have been induced by heavy rainfall and happened just west of the town. The Italian basin of the Mediterranean and the peninsula are often affected by patterns of intense precipitation. About 2300 people have been evacuated just before the slide happened. No deaths or injuries have been reported. The authorities have predicted that a landslide could be happening as they have indicated the signs on the road (Figure A1) The town of Maierato was affected by slope instability not only due to the heavy rainfall but also due to the existing geological structure, the plastic properties of soil of sliding surface, infiltration of water into the soil , erosion of soil at the toe of the slide and increasing ground water level. Back analysis indicates that cohesion is the most critical factor contributing to slope stability. Disciplines Earth Sciences | Physical Sciences and Mathematics Comments A Project design submitted to the Graduate Faculty of The University of Pennsylvania partial fulfillment of the Requirements for the Degree of Master of Science in Applied Geosciences Summer 2010. This other is available at ScholarlyCommons: https://repository.upenn.edu/msag_projects/2 LANDSLIDE OCCURANCE AT MAIERATO, S.ITALY – AN ENGINEERING GEOLOGICAL PERSPECTIVE By JAITHISH JOHN A Project design submitted to the Graduate Faculty of The University of Pennsylvania partial fulfillment of the Requirements for the Degree of Master of Science in Applied Geosciences Summer 2010 APPROVED BY: _________________________ _____________________________ Craig R.Calabria, Ph.D., P.E. Prof Edward L.Doheny,PG Primary Reader Secondary Reader DEDICATION This Project design is dedicated to my late parents, who taught me that the best kind of knowledge to have is that which is learned for its own sake and no task is too big if it is done one step at a time. It is also dedicated to my wife, Nuriya and our four children, Jerard, Jolene, Jeraldine and Jordan for their patience, support and encouragement for me to complete this project design. …the mountain falls and crumbles away… And the rock is removed from its place. Job 14:18 ii ACKNOWLEDGEMENT I would like to extend my thanks and gratitude to my advisors, Dr Craig Calabria and Professor Edward L.Doheny for their support and assistance in providing helpful weekly discussion and valuable comments as this project design took shape. Many thanks also goes to Dr Yvette Bordeaux for being a wonderful and helpful program advisor during my two years at the university of Pennsylvania. Also I would like to thank all the faculty lecturers at the Department of Earth and Environmental Science, University of Pennsylvania for their dedication to educate students in their field of expertise. I would also like to thank Dr Federico Falcini for his invaluable assistance for the coordination with the Italian geological bodies. Not to mention all the graduate students who have been supportive and cooperative over the last two years and it have been a valuable experience. I would like to extend my appreciation to the Minerals and Geoscience Department Malaysia and Public Service Department of Malaysia especially to Hajjah Saraya Bt Arbi for granting me the Federal Training Scheme Scholarship. iii TABLE OF CONTENTS page DEDICATION ii ACKNOWLEDMENT iii LIST OF TABLES v LIST OF FIGURES v ABSTRACT viii CHAPTER 1. Introduction 1 2. Topography and soil 6 3. Geology of the area 10 4. Rainfall and temperature 15 5. Environmental impact 21 6. Dynamics of Landslide 24 6.1. Liquefaction 31 6.2. Volume of landslide 32 6.3. Slope stability analysis 32 7. Conclusion 44 REFERENCES 45 iv APPENDICES Appendix A: Results of the slope stability analysis for FS = 1.0 48 Appendix B: Results of the slope stability analysis for FS = 1.747 50 Appendix C: Results of the slope stability analysis for FS = 0.821 52 Appendix D: Results of the slope stability analysis for FS = 0.999 54 Appendix E: Results of the slope stability analysis for FS = 1.007 56 LIST OF TABLES 4.1 Precipitation from 2000 –2009 16 4.2 Precipitation for the month of February 2010 17 4.3 Average monthly temperature 18 6.1 Table showing the results of the back analysis from the Maierato landslide 34 6.2 Summary of the parameters for the ASTABL7 computation 38 LIST OF FIGURES A.1 Landslide warning signs vii 1.0 Location map of Maierato, Calabria, Italy 1 1.1a Aerial view of landslide towards NNE 2 1.1b Aerial view of landslide towards east 2 1.2 Photograph of damaged house 3 1.3 Slope movement classifications (Varnes 1978) 5 2.0 Geological Map of the Maierato region 8 2.1 Outcrop exposure showing the evaporitic limestone/ marl 9 2.2 Close-up view of the evaporitic limestone/ marl 9 v 3.1a Photograph taken after the landslide on March 14, 2010 10 3.1b Photograph taken before the landslide on March 13, 2003 10 3.2 Photograph of soil mass after the landslide event 11 3.3 Seismotectonic map of S.Calabria 12 3.4 Landuse for orchards 13 4.1 Climate for the Maierato region 18 4.2 Mean annual rainfall for the Maierato region from 2000-2009 19 4.3 Rainfall precipitation for February 2010 19 4.4 Rainfall critical thresholds chart 20 5.1 Collapsed electric power pylon 22 5.2 View of Lake Angitola, a protected oasis 22 5.3 Houses in danger of collapse 23 5.4 Damaged hillside road 23 6.1 Cracks appearing on road parallel to the line of movement 25 6.2 Planar ledge in the clay layer 25 6.3 Shear failure as indicated by Mohr’s circle 26 6.4 Shear strength as a function of effective stress 27 6.5 Water forces acting on the failure surface 27 6.6 Tension crack on the upper slope 28 6.7 Slope being steepened and road repaired after a minor landslip 29 6.8 Minor landslide along the Circonvallazione Road 29 6.9 Map showing the approximate frontal landslide area 30 6.10 Topographical plan of the landslide area 31 vi 6.11 Cross section of the Maierato profile from B 32 6.12 Photo showing slope profile B – A 33 6.13 Linear develop of the cohesion-friction angle 36 6.14 GSTABL7 output for Maierato slope when FS = 1 39 6.15 GSTABL7 output for Maierato slope when FS = 1.747 40 6.16 GSTABL7 output for Maierato slope when FS = 0.821 41 6.17 GSTABL7 output for Maierato slope when FS = 0.999 42 6.18 GSTABL7 output for Maierato slope when FS = 1.002 43 vii ABSTRACT This paper focuses on the 15th February, 2010 Maierato landslide in the Calabria region of Italy. The slide is believed to have been induced by heavy rainfall and happened just west of the town. The Italian basin of the Mediterranean and the peninsula are often affected by patterns of intense precipitation. About 2300 people have been evacuated just before the slide happened. No deaths or injuries have been reported. The authorities have predicted that a landslide could be happening as they have indicated the signs on the road (Figure A1) The town of Maierato was affected by slope instability not only due to the heavy rainfall but also due to the existing geological structure, the plastic properties of soil of sliding surface, infiltration of water into the soil , erosion of soil at the toe of the slide and increasing ground water level. Back analysis indicates that cohesion is the most critical factor contributing to slope stability Figure A1: Photo showing the landslide warning sign (http://virtualglobetrotting.com) extracted 17 July, 2010 viii CHAPTER 1 INTRODUCTION: Landslides represent one of the most relevant natural hazards in Italy. Landslides do not occur in isolation; they are a product of their environment and in turn influence its condition. On February 15, 2010 in the Italian region of Calabria near the town of Maierato (Figure 1.0), a huge landslide (Figures 1.1a and 1.1b) occurred which has 32 villages having a population of 2,333 (2009 census). This slope movement phenomenon named the Maierato landslide affected the west part of the town and a few isolated housed were affected (Figure 1.2) and luckily no lives were lost. This landslide event was reported in all major medias around the globe. MAIERATO, ITALY Figure 1.0: Location Map of Maierato, Calabria, ITALY 1 Figure 1.1a: Aerial view of the landslide (toward NNE) ( http://ilquotidianodellacalabria.ilsole24ore.com) Extracted 17July,2010 Figure 1.1b: Aerial view of the landslide (toward East) (http://ilquotidianodellacalabria.ilsole24ore.com) Extracted 17 July, 2010. 2 Figure 1.2: Photo showing damaged house.(http://ilquotidianodellacalabria.ilsole24ore.com) Extracted 17 July, 2010.