Abstract—Experimental investigation of the effect of hydrophobic injection on siloxane basis on the properties of old- fashioned type of ceramic brick is presented in the paper. At the experimental testing, the matrix density, total open porosity, pore size distribution, sorptivity, water absorption coefficient, sorption and desorption isotherms are measured for the original, as well as the hydrophobic-injection treated brick. On the basis of measured data, the functionality of the hydrophobic injection for the moisture ingress prevention into the studied ceramic brick is assessed. Keywords—Brick masonry, siloxane hydrophobic injection, moisture ingress, functionality testing. I. INTRODUCTION RICK masonry usually suffers from moisture coming from several sources. In case of older brick buildings, where the horizontal water-proofing layer is usually missing, the moisture intakes especially from the subsoil. Other significant sources of moisture in building structures are the faults of eaves, water pipelines and improper construction design. Water in all its phases significantly decreases mechanical properties of masonry materials. Furthermore, in damp conditions porous building materials are susceptible to frost damage, because of the volume changes accompanying the phase conversion of water from the liquid into the solid phase. Water can deteriorate building materials and structure surfaces also by acid decomposition reactions. Typical example is sulphur dioxide that dissolves in water and partly forms sulphurous acid and sulphur trioxide that forms acid as well. Both acids decompose lime and lime-mixed binders in coatings and mortars. Z. Pavlík is with the Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, 166 29 Prague, Czech Republic (phone: +420-2-2435-4371; fax: +420-2-2435-4446; e-mail: pavlikz@fsv.cvut.cz). M. Keppert is with the Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, 166 29 Prague, Czech Republic (phone: +420-2-2435-4563; fax: +420-2-2435-4446; e-mail: martin.keppert@fsv.cvut.cz). M. Pavlíková is with the Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, 166 29 Prague, Czech Republic (phone: +420-2-2435-4688; fax: +420-2-2435-4446; e-mail: milena.pavlikova@fsv.cvut.cz). R. Černý is with the Department of Materials Engineering and Chemistry, Faculty of Civil Engineering, Czech Technical University in Prague, 166 29 Prague, Czech Republic (phone: +420-2-2435-5044; fax: +420-2-2435-4446; e-mail: cernyr@fsv.cvut.cz). Moist or damp buildings have been in several studies attributed to the negative health effects [1]. Due to the excessive moisture, several biological processes are evoked leading to the biological growth ranging from bacteria, algae, and fungi to moss [2]. Another serious problem for the functionality of building materials and buildings represents the decrease of thermal insulation function of materials with increasing moisture content. Since the thermal conductivity of water is approximately 0.60 W/mK at 20°C [3], which is more than 20 times higher than of the air, the thermal conductivity of damp material rapidly increases [4]. Since the negative effects of moisture presence in building materials and structures are quite obvious, there is necessary to prevent moisture ingress into the buildings for their whole service life. In case of the damp brick masonry, there are several methods that can be applied for its reconstruction and renovation. Among them, the use of injection substances is the most popular method for barring the liquid moisture transport from the subsoil. In this paper, the experimental investigation of the effectiveness of hydrophobic siloxane injection is presented in order to access its applicability at restoration of brick masonry. II. STUDIED MATERIALS AND SAMPLES The siloxane injection was applied into the old-fashioned type of ceramic brick produced by the brick factory Zlínské cihelny Ltd., Czech Republic. This brick was chosen in consideration of its composition and appearance that are very close to the original historical bricks that were one of the most often used building material in the Central European territory over the last centuries. The brick is poorly burnt, inhomogeneous, and its colour varies from bright red to greyish. The original brick size is 290 mm x 145 mm x 65 mm. Within the samples’ preparation, the brick was cut in halves and into the each part, a 100 mm deep hole of 20 mm diameter was bored. The prepared holes were then filled by siloxane injection Aquafin SMK. In this way, the free-flow injection was performed. For sample preparation see Fig. 1. 14 days after injection penetration the particular samples were cut from the treated brick halves, whereas the visibly injection saturated parts of the brick were chosen for experimental testing. Z. Pavlík, M. Keppert, M. Pavlíková, R. Černý Investigation of the Effectiveness of Siloxane Hydrophobic Injection for Renovation of Damp Brick Masonry B World Academy of Science, Engineering and Technology International Journal of Materials and Metallurgical Engineering Vol:6, No:1, 2012 123 International Scholarly and Scientific Research & Innovation 6(1) 2012 scholar.waset.org/1307-6892/1942 International Science Index, Materials and Metallurgical Engineering Vol:6, No:1, 2012 waset.org/Publication/1942