Local Site Effects and Incremental Damage of Buildings during the 2016 Central Italy Earthquake Sequence

Abstract

The Central Italy earthquake sequence initiated on 24 August 2016 with a moment magnitude M6.1 event, followed by two earthquakes (M5.9 and M6.5) on 26 and 30 October, caused significant damage and loss of life in the town of Amatrice and other nearby villages and hamlets. The significance of this sequence led to a major international reconnaissance effort to thoroughly examine the effects of this disaster. Specifically, this paper presents evidences of strong local site effects (i.e., amplification of seismic waves because of stratigraphic and topographic effects that leads to damage concentration in certain areas). It also examines the damage patterns observed along the entire sequence of events in association with the spatial distribution of ground motion intensity with emphasis on the clearly distinct performance of reinforced concrete and masonry structures under multiple excitations. The paper concludes with a critical assessment of past retrofit measures efficiency and a series of lessons learned as per the behavior of structures to a sequence of strong earthquake events.

Norcia and Amatrice: A Comparison of the Two Historic Centres’ Performance Under the Central Italy Earthquake Sequence

“…As discussed by [19], a deterministic approach might be more relevant for the assessment of historic centres, mainly because, if the seismicity of the area is well known, a credible and reliable earthquake scenario can be developed and be directly correlated to the building stock performance [24]. The 2016 Central Italy seismic swarm occurred in an area with the highest seismic hazard in Italy, where the PGA values expected with a probability of exceedance of 10% in 50 years are higher than 0.25 g [2] [4]. The information on the records of the two events, extracted from the ESM database [20], are reported in Acceleration response spectra are extracted from the ESM database [25] and shown in The August event (a) has the largest ever peak ground acceleration recorded on Italian soil at the Amatrice instrument.…”

“…According to the published shake maps [2], and as discussed further in section 4, the seismic demand for the first event was considerably larger in Amatrice for stiffer structures, than in Norcia. Although the local soil is assigned the same class B according to EC8 [3] the topography of the two towns is substantially different, with Amatrice laid out at the top of a hill, while Norcia lays in a valley, contributing to substantial differences in amplification of the seismic shaking [4].…”

Scenario-Based Seismic Risk Assessment for Buried Transmission Gas Pipelines at Regional Scale

“…All the geotechnical failures historically recorded were very close to pipelines locations characterized as damaged (DS1) according to the methodology. In the future, the proposed damage maps can be integrated with satellite surveys of geotechnical failures [which are increasingly available nowadays and are often adopted in postearthquake recognition (Sextos et al 2018)] in order to increase the level of confidence in the localization of potential damage.…”

TLS for Detecting Small Damages on a Building Façade

“…Aging, humidity, infiltration, solar radiation and other physical, chemical and biological factors cause the need for monitoring building structures and their periodical restoration (Giacomucci et al, 2011, Hällström et al, 2009, Sextos et al, 2018. Monitoring the status of building façades is a task typically done by a human operator (Bauer et al, 2014), which has to carefully inspect them in order to determine areas that require restoration or maintenance.…”