Issue 51

M. Pepe et alii, Frattura ed Integrità Strutturale, 51 (2020) 504-516; DOI: 10.3221/IGF-ESIS.51.38 511 (a) (b) (c) Figure 5 : Collapse mechanism for Example 2, horizontal live load: ( a ) ALMA 2.0, ( ) FEM/DEM, ( ) FEM (a) (b) (c) Figure 6 : Collapse mechanism for Example 3, horizontal live load: ( a ) ALMA 2.0, ( ) FEM/DEM, ( ) FEM Fig. 5 refers to results obtained for Example 2. Results are similar to those of the smaller panel previously analyzed, with a hinging behavior which exhibits a rotation of the upper right portion of the panel and three ‘stair-stepped’ cracks of the wall now obtained with all the three models. Also, in this case the FEM-DEM present a sliding of the blocks not observed into result of the other models but, by the adoption of a fictitious cohesion value for head joints, could allow to obtain a mechanism less influenced by sliding. Fig. 6 refers to results obtained for Example 3, characterized by the presence of an opening. In this case the results obtained with the three models are exactly the same, with a hinging behavior which implies the rotation of half panel around a hinge positioned about at the lower right corner of the panel. All the models compute a principal diagonal crack passing through the opening. Some slight differences could be pointed out for the mechanism corresponding to the FEM, as for example the position of the hinge which is located at ground level (for Limit Analysis and FEM/DEM it is positioned upon the first row of blocks) and the absence of movement of the portion of the panel to the left of the opening (the other two models detect a slight rotation of this macro-block around a hinge positioned exactly at the left lower corner of the window). (a) (b) (c) Figure 7 : Collapse mechanism for Example 4, horizontal live load: ( a ) ALMA 2.0, ( ) FEM/DEM, ( ) FEM