Sensitivity-based approaches to model updating have become widely used because of their capability to calibrate themodel by taking into account the influence of updating parameters associated to different structural elements. Global sensitivity analysis (SA) allows model updating to be carried out even in the case of elevated uncertainty about the material characteristics. Architectural heritage structures deserve specific attention on account of their intrinsic geometrical complexity and heterogeneity. In this article, the concept of global SA is applied for the first time to complex monumental structures, and a comparative view is offered on more classical local sensitivity approaches. Different finite element (FE) calibration techniques—via global and local SA—were applied to the intriguing case of the church of S. Maria del Suffragio in L'Aquila (Italy), severely damaged by the 2009 earthquake. The FE updating was based on experimental data acquired by a dynamic monitoring system. Finally, calibration strategies were assessed through time history analyses by comparing the responses to the recorded seismic even

The research shows the results of experimental tests to establish the dynamic parameters of fiber-reinforced polymer (FRP) structural elements in the free vibration field. The tests and the analysis consider the simply supported configuration of pultruded elements characterized by glass fiber reinforcement, glass fiber-reinforced polymer (GFRP) and the thermosetting vinylester matrix subjected to flexural, transversal, and torsional vibrations. Comparison between the experimental results and numerical analysis and the finite element method is also presented. The dynamic response of GFRP structural elements is compared with the behavior of steel and aluminum elements. The results show a good performance, especially in the case of open cross-sectional profiles, considering the advantages deriving from the ratio between the dead load and total load of fiber reinforced composite material. Finally, the use of pultruded GFRP elements for new-built decks is investigated to detect possible resonance phenomena due...

The church of S. Pietro di Coppito in L'Aquila is a case study of complexity under the structural point of view; the damage due to earthquake in 2009 is thus not easy to be interpreted. After a general overview of the damage, in situ test results are presented with a modal analysis, and finally the seismic response of the church is analyzed via subdivision into macro-elements with mutually independent structural responses. Particularly, the facade has moved out-of-plane, leading to the partial collapse of one of its upper edges and to the detachment from the nave walls. These two collapse mechanisms were studied by means of both linear and non-linear kinematics analyses, and a dynamic non-linear rigid body analysis was also performed. The triumphal arch, in contrast, was displaced mainly within its plane and was also studied by linear and non-linear kinematics limit analysis. The results thereby obtained were then compared with the outcomes of a series of finite-element non-linear incremental (push-over) analyses. On the basis of the analytical results and level of structural knowledge, this work is able to interpret the actual collapse process clarifying the global and local mechanisms and determining, then, the limits of each analytical tool. © 2014 Taylor and Francis Group, LLC

This paper presents the results from a combined experimental and advanced computational study to understand the dynamic response of a pultruded fiber-reinforced polymer (FRP) sheet pile of 9 m length that is installed into the ground near Venice, Italy. The peak embedment force of 10 kN is applied at the top as a sinusoidal compression force having a maximum frequency of circa 760 Hz. Physical measurements from accelerometers are reported for the lateral deformation response of a single sheet pile and of a unit restrained by an installed waterfront barrier. A finite-element modeling methodology for the two test configurations is developed by using the Strand7 code, so that advanced computational results can be compared against the field application measurements. Closed-form equations for the fundamental frequency are developed, with one accounting for the presence of rotary inertia and shear deformation. Dynamic responses at different embedment lengths (1–7 m) are examined, and a very good correlation is found between theory and practice. Numerically, the performance of the FRP sheet pile is compared with the response of a fictitious sheet pile of steel and with two new FRP geometries that increase stiffness to minimize flexure about the minor axis of bending. By increasing the mass by 10%, the maximum lateral displacement can be the same as the steel unit and $1/20$ of the tested FRP unit. Findings of the research demonstrate that the FRP unit can be installed by using the same pile driving rig and procedure for steel sheet piling.