Materials and Structures

, 51:156 | Cite as

Consolidation effectiveness of modified Si-based nanocomposites applied to limestones

  • E. Ksinopoulou
  • A. BakolasEmail author
  • A. Moropoulou
Original Article


One of the main issues in the field of Monument Protection is the degradation of limestones as a result of the action of various weathering mechanisms. The modification of widely used silicon-based materials for stone consolidation is intended to overcome the well-known drawbacks of these materials, such as shrinkage and cracking tendency during drying. The addition of nano-dispersions into a silica matrix aims to enhance their effectiveness in several ways, by improving their properties and their viscoelastic behavior. The objective of the current research was the application and evaluation of Si-based modified nanocomposites of optimized composition. The materials were applied to two types of porous stone and the assessment of their compatibility and performance was carried out by using both laboratory techniques and methods (SEM, MIP, TMA, Water Absorption by Capillarity, determination of Water Vapor Permeability) and non-destructive techniques (Ultrasound Velocity determination, Colorimetry). To study the resistance of the treated samples to soluble salt crystallization, accelerated aging tests were performed in sodium sulfate cycles. The modified consolidants consist of an ethyl silicate matrix reinforced with colloidal silica (SiO2) nano-particles and titania (TiO2) particles. Based on the results, the consolidating material does not significantly alter the characteristics of the microstructure and the appearance of stones, allowing the passage of water vapor, while increasing their mechanical properties. Furthermore, the accelerated ageing tests revealed that the treated samples have a higher resistance to the action and crystallization of soluble salts in comparison to untreated.


Nanoparticles Stone consolidation Nanosilica Stone conservation Salt cycles 



This research has been co-financed by the European Union (European Social Fund—ESF) and Greek national funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF)—Research Funding Program: Heracleitus II. Investing in knowledge society through the European Social Fund.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© RILEM 2018

Authors and Affiliations

  1. 1.Department of Materials Science and Engineering, School of Chemical EngineeringNational Technical University of AthensAthensGreece

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