Experimental investigation on bricks from historical Venetian buildings subjected to moisture and salt crystallization Paolo Foraboschi ⇑ , Alessia Vanin Dipartimento di Architettura Costruzione Conservazione, Università IUAV di Venezia, Dorsoduro 2206, 30123 Venice, Italy article info Article history: Received 20 March 2014 Received in revised form 21 May 2014 Accepted 25 June 2014 Available online 5 July 2014 Keywords: Brackish water Brick’s compression strength Environmental actions Moisture Salt crystallization abstract The research presented in this paper investigated the mechanical behavior of bricks subjected to moisture and salt crystallization, and aimed at determining the mechanical degradation of bricks due to these environmental factors. Compression tests were performed on bricks removed from an historical Venetian build- ing. The paper presents the experimental campaign and the results. The analysis of the experimental results provided novel information about the effects of moisture and salts on the compression strength of bricks. In particular, the experimental results demonstrate that moisture significantly reduces the compression strength of a brick; the greater the moisture content the lower compression strength, all other condition being equal, in particular salt concentration inside the brick. Moreover, the experimental results demon- strate that salts together with moisture significantly reduce brick compression strength, while salts without moisture increase brick compression strength. However, the crystalli- zation of these salts can cause subflorescence and efflorescence inside the bricks, which eventually reduce the compression strength of the bricks and the masonry. The paper provides a discussion on the results that extends the outcomes to any masonry building subjected to brackish water or tides. The conclusions are devoted to safeguarding and conservation of masonry buildings that suffer from humidity and salt crystallization. Ó 2014 Elsevier Ltd. All rights reserved. 1. Introduction Venetian buildings have to endure the lagoon environment, which is aggressive since the water of the lagoon is brackish (dissolved salt content) and the lagoon is subject to high variations of water level (daily tidal cycle). Salinities in the Venice lagoon were recorded from May 2005 to February 2007, and chloride concentrations in pore fluids were measured up to 1.50 m [1]. The measures showed that salinity in the Venice lagoon is significant, as well as its vari- ations during the seasons. The cycle of the Venetian lagoon tide has a period of approximately 21 h and 30 min, and a difference between the high tide and ebb tide (not the following ebb tide, but the difference between the high waters and the low waters) that may sur- pass 1.70 m and that has an average value greater than 0.60 m. The combination of brackish (briny) water and tides (high and low water) of the Venetian lagoon was modeled [2]. The simulations confirmed that this combination of conditions causes the Venetian buildings to withstand severe environmental actions. http://dx.doi.org/10.1016/j.engfailanal.2014.06.019 1350-6307/Ó 2014 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. Tel.: +39 041 2571289; fax: +39 051 392909. E-mail address: paofor@iuav.it (P. Foraboschi). Engineering Failure Analysis 45 (2014) 185–203 Contents lists available at ScienceDirect Engineering Failure Analysis journal homepage: www.elsevier.com/locate/engfailanal