Silvia Santini

Damage patterns in the town of Amatrice after August 24th 2016 Central Italy earthquakes

The impact of the two seismic events of August 24th 2016 on the municipality of Amatrice was highly destructive. There were 298 victims, 386 injured, about 5000 homeless, and the historical center of the town suffered a great number of partial and total collapses. The 260 strong motion records obtained for the first event were analyzed and plotted in a shakemap, comparing them with the macroseismic damage surveys made in 305 localities. On the basis of an inspection survey made in September 2016, a map of the damage patterns of the buildings in the historical center was elaborated according to the EMS 98 classification. The damage level resulted very high with more than 60% of the inspected buildings showing partial or total collapse. The elevated level of destruction was mainly caused by the high vulnerability of the masonry buildings, mostly due to specific vulnerability factors such as the poor quality of masonry, the lack of connections between walls and the poor connection between external walls and floors.

Experimental program for pseudodynamic tests on repaired and retrofitted bridge piers

ABSTRACT This research aims to study the seismic performance of existing r.c. bridge piers specimens heavily damaged after previous pseudodynamic tests and actually repaired and upgraded by using self compacting concrete, stainless steel rebars and CFRP wrapping. Pier specimens are representative of tall and squat circular r.c. piers designed according to Eurocode 8 or Italian Code before 1986. The study comprehends preliminary tests carried out on self compacting concrete and stainless steel bars, as well as on going pseudodynamic tests in order to evaluate the effectiveness of adopted repairing and upgrading techniques to increase both ductility and shear strength.

Damage, Vulnerability and Retrofitting Strategies for the Molise Hospital System Following the 2002 Molise, Italy, Earthquake

The earthquake of October 31, 2002, inflicted moderate damage on the region of Molise in southern Italy. However, it attracted much attention because almost all the victims were children killed in the structural failure of their primary school. This paper focuses on a different, but equally important, structural type: hospitals. The earthquake left them largely untouched. In the paper we first give a detailed picture of the structural damage and of the organization of emergency operations. Then we try to give guidance about the most effective retrofitting strategies for the regional hospital system as a whole, following a methodology developed in Nuti and Vanzi (1998b), which has been adjusted for this case study. Depending on the community decision criteria, the hospitals of Campobasso and Bojano appear to have the highest priority for retrofitting, even though they were unscathed by the event.

Rapid Repair Technique to Improve Plastic Dissipation of Existing Chinese RC Bridges

A rapid repair and retrofitting technique for reinforced concrete (rc) Chinese existing bridges damaged by a strong earthquake, is proposed and tested. These bridges were designed according to Chinese codes [1] [2] [3] but with insufficient transversal steel reinforcement. The damaged rebar and concrete parts were replaced by new bar systems and concrete cast respectively. Finally, a C-FRP wrapping was applied to increase the insufficient shear strength and to guarantee the necessary ductility in plastic hinge. This repair technique is an upgrade of the one tested with very good results during a previous experimental research [4] on bridge designed according to old Italian code [5] without proper seismic details. A new bar system assures that plastic dissipation is distributed in plastic hinge only. Some pier specimens (in scale 1:6) were built with and without the new bar systems. These specimens were tested by cyclic tests at Fuzhou University lab (China) to evaluate the effectiveness of the intervention.

Experimental tests on FRP shear retrofitted RC beams

The paper presents the results of experimental tests on two reinforced concrete beams retrofitted by means of FRP strips. Both beams have been removed from the structure of one of the older r.c. buildings in Rome, built up at the beginning of XX century. The experimental tests are carried out in the Laboratory of the Department of Structures at the University of Roma Tre. Before retrofitting, preliminary tests are performed in order to evaluate the homogeneity and the mechanical characteristics of concrete, and elastic tests (shear/bending tests) in order to evaluate the original state of the beams. After retrofitting, failure tests (shear/bending tests) on the beams togheter with compressive tests on concrete and tension tests on rebars are carried out. All performed tests demonstrate the capability of repairing and retrofitting on r.c. structures of modest quality, moreover revealing some aspects due to the fragile behaviour of carbon fibers.