PSI - Issue 29

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Stefano Galassi et al. / Procedia Structural Integrity 29 (2020) 126–133 Galassi et l. / Structural Int grity Procedia 00 (2019) 000 – 0 0

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Fig. 7. Parametric analysis on the effectiveness of joint inclination.

Fig. 7 shows, for eachpatternof the horizontal actions, the uniform loadpattern in +Xdirection (ULP+X) and in - X direction (ULP-X) and the linear load pattern in +X direction (LLP+X) and -X direction (LLP+X), an increaseof the performance of the structure as the inclination of the joints increases. Table 2, where the results of the parametric analysis are reported in detail, shows that thestructure, regardless of theactual strength of thematerial, can withstand an average increase in the collapse load around20-21%for horizontal actions in +Xdirection andaround25-26% for horizontal actions in -Xdirection.

Table 2. Results of the parametric analysis.

Mean percentage increase [%]

Joint inclination [°]

Collapse factor

Load pattern

0

9

18

27

36

0.119 0.106 0.089 0.078

0.125 0.131 0.136 0.143 0.113 0.119 0.125 0.132 0.094 0.098 0.103 0.108 0.085 0.089 0.093 0.099

20.17 24.53 21.35 26.92

ULP+X ULP-X LLP+X LLP-X

α 0

6. Conclusions In this paper the first results of the seismic vulnerability analysis of the remains of theancient colonnade in the civil forum of Pompeii are presented. A2D-rigid block model describing the actual configurationof thestructure has been used. The seismic action was simula ted through a pa ttern, both uniform and linear, of in-plane and out-of-plane increasing horizontal forces. The seismic vulnerability was investiga ted by computing the factor of the horizontal forces that activates the collapse mechanismcharacterizedby rotational hinges in correspondence to the contact joints between blocks. As expected, the structure resultedmore vulnerable in the case of out-of-planeactions. Currently, the authors are developing a new release of the computer program BrickWORK to model a 3D-rigid block structure, in order to consider the effectivestrength capacityof thestructure that, in the rea lity, could developa more complex collapse mechanismwith rigid blocks partitionedby cylindrical and/or spherical hinges. Acknowledgements Da ta and information presented in this paper are a part of the ongoingdegree thesis in Architecture ofMaria Luisa Sa tta, a co-author of this contribution. The topic addressed herein if framed within the research project, made in cooperation between the Department of Architecture of the University of Florence and the Parco Archeologico of Pompeii, a imeda t theanalysis, interpretation andassessment of theseismic vulnerability of the constructiveelements