A Method to Calculate the Support Length of Beams Resting on Masonry Walls.

Rehabilitation, strengthening, and retrofitting of existing masonry buildings represent an important challenge for the construction engineering field. Often, slab strengthening/retrofitting is performed by replacing existing timber and steel beams or by adding new beams to improve the slab load-carrying capacity. The computation of the stresses at the beam-masonry interface (i.e., the contact pressure) is crucial to properly design the beam support length, preventing local failure of masonry and beam. This paper presents a simple analytical procedure to compute the contact pressure at the beam-masonry interface. The analytical procedure is validated by comparison between analytical and corresponding numerical results obtained by finite element modeling. Different types of beam (solid and laminated timber beams and steel beams) were considered, as well as different support conditions (simply resting on the wall considering different support lengths or fully embedded). The results obtained show that the method proposed is simple and reliable, which makes it suitable for professional practice.

Assessment of the shock adsorption properties of bike helmets: a numerical/experimental approach.

In this paper, a numerical and experimental study of the shock absorption properties of bike helmets is presented. Laboratory compression and tensile tests were carried out on samples of expanded polystyrene (EPS) and polycarbonate (PC), respectively constituting the internal shock absorption layer and the external hard shell of composite helmets. The measured responses of the two materials were then exploited to calibrate the relevant elasto-plastic constitutive models, adopted in full-scale finite element analyses of a helmet subject to standardized impacts. The simulations allowed assessing the time evolution of the acceleration measured inside the headform (according e.g., to EN 1078) and the failure mechanisms of the helmet, if any, as induced by the localization of plastic deformations.

Surveying and monitoring for vulnerability assessment of an ancient building.

This paper examines how surveying and monitoring improve our knowledge about ancient buildings, allow the interpretation of their structural response and help in the search for the best solutions for their conservation. The case study of Palazzo del Capitano in Mantua (Italy) is analyzed. In particular, the attention is focused on the use of a Terrestrial Laser Scanner (TLS) for surveying and monitoring too, considering that the building structural control has been performed in combination with other traditional topographic techniques such as geometric leveling and topographic networks for 3D control based on measurements through total stations. The study of TLS monitoring has been tested only in the last decade and it is an innovative method for the detection of displacements of particular surfaces. Till now the research has focused only on the use of TLS monitoring to control large structures and in particular landscape situations; thus its use for a civil construction and historical buildings is a new field of investigation. Despite the fact technological development and new methodologies seem offer new future potential for the analysis of ancient buildings, currently there are still important limits for the application of the investigated surveying and monitoring techniques.