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1.
This paper presents the findings from a study on gravity-induced slope deformations along the northern slope of Mt. Nuria (Rieti-Italy). The slope extends from the village of Pendenza to the San Vittorino plain and hosts the Peschiera River springs, i.e. the most important springs of the Central Apennines (average discharge: about 18 m3/s).
Detailed geological-geomorphological and geomechanical surveys, supported by a site stress-strain monitoring system and laboratory tests, led us to define the main evolutionary features of the studied phenomena. Based on the collected data, a “geological-evolutionary model” was developed with a view to identifying a spatio-temporal correlation between relief forms, jointing of the rock mass and its stress conditions. The geological-evolutionary model was expected to improve numerical simulations and to test our assumptions.
The numerical model also allowed us to simulate changes in the stress-strain conditions of the rock mass and correlate them with jointing, seepage, as well as with site-detected and site-monitored forms and deformations. In particular, significant relations between seepage, tensile stresses within the rock mass, karst solution and collapse of cavities were identified. 相似文献
2.
Fiorucci M. Iannucci R. Lenti L. Martino S. Paciello A. Prestininzi A. Rivellino S. 《Natural Hazards》2016,86(2):345-362
A monitoring system is operative in the Peschiera Springs slope (Central Apennines, Italy) to mitigate the landslide risk related to the hosted main drainage plant of Rome aqueducts by providing alert warning. Such a strategy allows to avoid out-of-service episodes so reducing extra-costs of water distribution management. The Peschiera Springs slope is involved in a rock mass creep characterized by an average steady strain rate of 1 mm year−1 and responsible for several landforms including sinkholes, subvertical scarps and trenches. Moreover, an average aquifer discharge of 19 m3 s−1 causes an intense limestone dissolution concentrated in correspondence with release bands and discontinuities that dislodge the jointed rock mass. Since 2008, an accelerometric network has been operating within the slope; about 1300 microseismic local events were recorded up to now, distinguished in failures and collapses. A control index, based on frequency of occurrence and cumulative energy of the recorded microseismic events was defined to provide three levels of alert. In 2013, a temporary nanoseismic Seismic Navigation System (SNS) array was installed inside a tunnel of the drainage plant to integrate the pre-existent seismic monitoring system. This array allowed to record 37 microseismic events, which locations are in good agreement with the evolutionary geological model of the ongoing gravitational slope deformation. In 2014, a permanent nanoseismic SNS array was installed in the plant and allowed to record several sequences of underground collapses including more than 500 events. The nanoseismic monitoring system is allowing to: (1) increase the detection level of the monitoring system; (2) locate hypocentres of the events; and (3) detect precursors of the strongest events.
相似文献3.
Seismometer arrays have been widely applied to record collapse by controlled explosion in mines and caves. However, most underground failures are natural events, and because they can occur abruptly, underground failures represent a serious geological hazard. An accelerometric array installed on 4 September 2008 has been used to manage the geological risk of the Peschiera Springs drainage plant of Rome??s aqueduct, which is located in the Central Apennines approximately 80?km from Rome, Italy. The plant occupies a karstified carbonatic slope that is extensively involved in gravitational deformations, which are responsible for underground failures such as cracks and collapses. To distinguish among different types of recorded events, an automated procedure was implemented based on the duration, peak of ground acceleration (PGA) and PGA variation in the recordings of the plant??s accelerometric stations. The frequencies of earthquakes and micro-earthquakes due to underground failures are, in general, well correlated. Nevertheless, many underground failure sequences can be directly associated with the continuous deformations that affect the slope. The cumulative Arias intensity trend derived for the underground failures combined with the failure and earthquake frequencies enabled the definition of a control index (CI) that identifies alarming or emergency conditions. The CI can be used as a tool for managing the geological risk associated with the deformational processes that affect the drainage plant. 相似文献
4.
A methodology is proposed to determine design earthquakes for site-specific studies such as the siting of critical structures (power plants, waste disposals, large dams, etc.), strategic structures (fire stations, military commands, hospitals, etc.), or for seismic microzoning studies, matching the results of probabilistic seismic hazard analyses. This goal is achieved by calculating the source contribution to hazard and the magnitude–distance deaggregation, showing that, varying the selected frequency and the level of hazard, the reference earthquakes are changed as a result. A procedure is then adopted to minimize the residuals between the uniform hazard spectrum (target motion) and the design earthquake spectrum, to provide a specific earthquake scenario encompassing all the frequencies of the target motion. Finally, some considerations on the use and the influence exerted by ground motion uncertainty (σ) on hazard deaggregation are outlined. 相似文献
5.
Displacement patterns of a landslide affected by human activities: insights from ground-based InSAR monitoring 总被引：2，自引：0，他引：2
Francesca Bozzano Ivan Cipriani Paolo Mazzanti Alberto Prestininzi 《Natural Hazards》2011,59(3):1377-1396
Landslides interacting with large infrastructures represent a major problem for the economy, society as a whole, and the safety
of workers. Continuous monitoring for 23 months using an integrated platform with a ground-based SAR interferometer (GB-InSAR),
a weather station, and an automatic camera gave us the opportunity to analyze the response of an unstable slope to the different
phases of work. The deformational behavior of both the natural slope and the man-made structures was recorded and interpreted
in relation to the working stages and the rainfall conditions during the whole monitoring period. A typical pattern of displacement
was identified for shallow landslides, debris produced by the excavation and gabions, metallic walls, and anchored bulkheads.
Furthermore, insights into the dynamics and behavior of the slope and the man-made structures that interact with the landslide
were obtained. Extreme rainfall is the main trigger of shallow landslides and gabion deformations, while anchored bulkheads
are less influenced by rainfalls. Movement of debris that is produced by excavations and temporary metallic barrier deformation
are closely related to each other. The herein proposed monitoring platform is very efficient in monitoring unstable slopes
that are affected by human activities. Moreover, the recorded patterns of displacement in the slope and the man-made structures
can be used as reference data for similar studies and engineering designs. 相似文献
6.
M. Fiorucci R. Iannucci L. Lenti S. Martino A. Paciello A. Prestininzi S. Rivellino 《Natural Hazards》2017,86(2):345-362
A monitoring system is operative in the Peschiera Springs slope (Central Apennines, Italy) to mitigate the landslide risk related to the hosted main drainage plant of Rome aqueducts by providing alert warning. Such a strategy allows to avoid out-of-service episodes so reducing extra-costs of water distribution management. The Peschiera Springs slope is involved in a rock mass creep characterized by an average steady strain rate of 1 mm year?1 and responsible for several landforms including sinkholes, subvertical scarps and trenches. Moreover, an average aquifer discharge of 19 m3 s?1 causes an intense limestone dissolution concentrated in correspondence with release bands and discontinuities that dislodge the jointed rock mass. Since 2008, an accelerometric network has been operating within the slope; about 1300 microseismic local events were recorded up to now, distinguished in failures and collapses. A control index, based on frequency of occurrence and cumulative energy of the recorded microseismic events was defined to provide three levels of alert. In 2013, a temporary nanoseismic Seismic Navigation System (SNS) array was installed inside a tunnel of the drainage plant to integrate the pre-existent seismic monitoring system. This array allowed to record 37 microseismic events, which locations are in good agreement with the evolutionary geological model of the ongoing gravitational slope deformation. In 2014, a permanent nanoseismic SNS array was installed in the plant and allowed to record several sequences of underground collapses including more than 500 events. The nanoseismic monitoring system is allowing to: (1) increase the detection level of the monitoring system; (2) locate hypocentres of the events; and (3) detect precursors of the strongest events. 相似文献
7.
M. Floris F. Bozzano C. Strappaveccia V. Baiocchi A. Prestininzi 《Environmental Earth Sciences》2014,72(11):4223-4236
This paper presents the results of analyses measuring variations in anthropic pressure and the influence of anthropic pressure on the variations in subsidence rates from 1954 to 2005 in the Tivoli-Guidonia area, located to the East of Rome, Italy. In the last 60 years, this area underwent exceptional demographic growth, as well as an increase in the quarrying and hydrothermal industries. The calculation of the increase in anthropic pressure was based on two factors: the expansion of built-up areas and the increase in quarrying. Photogrammetric techniques permitted a multi-temporal analysis of aerial photos taken in 1954, 1985, 1993, 1998 and 2005. The aim of this analysis was to estimate the increase in both urban surface area and travertine quarrying. Non-conventional techniques, such as the reconstruction of photograms using photo retouching software, allowed for the use of aerial photos from 1954. These photos were fundamental for establishing a medium-term evaluation of anthropic activity in the area. The results of the photogrammetric analysis were compared to the phases of acceleration and stabilization in subsidence phenomena, deduced from a RADAR interferometry study published by the Italian Ministry of the Environment. This comparison showed a close relationship between the rise and temporary halt of anthropic development and the rise and fall of subsidence rates. Furthermore, data on the distribution of private wells in the study area, variations in the groundwater table level and the precipitation regime were analyzed, but, although helpful in defining the geological context and considerable transformations of the territory, they were considered as qualitative data due to the lack of systematic measures or an unclear relationship to the variations in subsidence rate. Despite the difficulties involved in evaluating both the amount of anthropic pressure and the role of different human activities on environmental change, it was possible to estimate the variations in anthropic pressure and their influence on potentially dangerous geological processes. 相似文献
8.
Research and development of advanced technologies for landslide hazard analysis in Italy 总被引：2，自引：0，他引：2
Francesca Bozzano Paolo Mazzanti Alberto Prestininzi Gabriele Scarascia Mugnozza 《Landslides》2010,7(3):381-385
The Research Centre on Prediction, Prevention and Control of Georisks, "Sapienza Università di Roma" (CERI) was selected as
one of the World Centres of Excellence on Landslide Risk Reduction (WCoE) under the title of “Research and development of
advanced technologies for landslide hazard analysis in Italy” in the period 2008–2011. The present paper provides background
information on the activities carried out by the CERI, in the frame of the WCoE network. Pre-defined purposes have been achieved
by the implementation of integrated monitoring systems and early warning systems for landslides movements. The application
of GBInSAR technique for monitoring landslides interacting with infrastructures is discussed, and two case histories are presented.
It is shown that this technique is particularly suitable for the displacements monitoring of landslides interacting with infrastructures,
thanks to its peculiar features (i.e. areal mapping, operability under every weather and lighting conditions and continuous
and completely remote monitoring). Hence, it can be considered a very important tool for the reduction of risks connected
to the realisation and activity of large infrastructures. 相似文献
9.
This study aims at investigating the value added by an explicit representation of floodplain processes in hydraulic models, by comparing the results of a pure 1D model to the ones of an integrated 1D-2D model. The analysis is performed on a 96 km reach of the River Po (Italy). For this test site, two different model structures (1D and 1D-2D) are implemented and compared. The models are first calibrated using high water marks of a high magnitude event and then validated by means of a coarse resolution space-borne flood extent map of a low-magnitude event. The explicit inclusion of 2D features strongly improves the performance of the model, both in terms of accuracy and robustness. The possible causes of this behaviour are investigated and some statements are drawn based on the analysis of the features of the two flood events. Some general conclusions on the effect of the choice between 1D and 2D models arise from the analysis of the calibration-validation procedure. In this context a new measure of fit is proposed, to be used if binary (wet/dry) observations are available and is proven to be able to better distinguish among different sets of model parameters. Lastly, the study also shows the ability of timely low resolution satellite imagery to assist the selection of the most appropriate hydraulic model structure. 相似文献
10.
Earthquake-induced ground failures in Italy 总被引：8，自引：0，他引：8
The National Catalog of Ground Failures Induced by Strong Earthquakes in Italy (CEDIT), is described. The catalog holds data on ground failures triggered by the earthquakes that occurred in Italy in the last millennium and which had a nominal epicentral intensity equal to or greater than VIII in the Mercalli–Cancani–Sieberg (MCS) intensity scale. The ground effects reported in the catalog are the following: landslides, fractures, liquefaction, surface faulting, and topographic changes of the ground level (subsidence, settlements, tilting, and so on). Each effect is described in terms of seismological parameters of the triggering earthquake, site coordinates and administrative code, lithology and kinematic type of the ground failure. The catalog represents a tool to assess the susceptibility of geologic materials to ground shaking, and to validate predictive models of seismically induced ground displacements (scenarios of earthquake-induced geologic risks). In the context of this study, a simple statistical analysis of the database yielded useful relations between the parameters of the triggering earthquakes and the related effects. 相似文献