Partial collapse of a ventilated stone façade: Diagnosis and analysis of the anchorage system

The mechanical behaviour of transventilated façades performed by natural stone is necessarily based on the correct execution of both anchoring elements on the stone cladding as in the ones corresponding to the enclosure support, either with brick masonry walls or reinforced concrete walls. In the case studied in the present work, the origin of the damages suffered on the façade of a building located in Alcoy has been analyzed, where the detachment of part of the outer enclosure occurred. This enclosure is a transventilated façade formed by Bateig Blue stone tiles. To this end, “in situ” tests of the anchoring systems employed have been performed, as well as laboratory tests of mechanical characterization of the material and of different types of anchor, comparing these results with those obtained in both the simplified analytical models of continuum mechanics as developed by the Finite Element Method (FEM).

Evaluation of Two Alternative Procedures for Measuring Airflow Resistance of Sound Absorbing Materials

It is well known that sound absorption and sound transmission properties of open porous materials are highly dependent on their airflow resistance values. Low values of airflow resistance indicate little resistance for air streaming through the porous material and high values are a sign that most of the pores inside the material are closed. The laboratory procedures for measuring airflow resistance have been stan- dardized by several organizations, including ISO and ASTM for both alternate flow and continuous flow. However, practical implementation of these standardized methods could be both complex and expensive. In this work, two indirect alternative measurement procedures were compared against the alternate flow standardized technique. The techniques were tested using three families of eco-friendly sound absorbent materials: recycled polyurethane foams, coconut natural fibres, and recycled polyester fibres. It is found that the values of airflow resistance measured using both alternative methods are very similar. There is also a good correlation between the values obtained through alternative and standardized methods.