Title:
Self Healing Of Cement Based Materials Engineered Through Crystalline Admixtures: Experimental Results From A Multinational University Network
Author(s):
Liberato Ferrara; Isaia Albertini; Ravindra Gettu; Visar Krelani; Simone Moscato; Francesco Pirritano; Marta Roig Flores; Pedro Serna Ros and Swathi M. Theeda
Publication:
Symposium Paper
Volume:
305
Issue:
Appears on pages(s):
13.1-13.10
Keywords:
self healing, crystalline admixtures, normal strength concrete, fiber reinforced concrete, high performance fiber reinforced cementitious composites, permeability
DOI:
10.14359/51688573
Date:
9/1/2015
Abstract:
Self-healing cementitious composites are a broad category of smart construction materials to which strong and highly qualified research efforts are currently being devoted worldwide, with the aim of providing a sound scientific background to their consistent, and – design-wise – “consciously safe”, use in the engineering practice. Tailored additions can be employed to enhance the self-healing capacity, among which the so-called crystalline admixtures, play a prominent role. Crystalline admixtures consist of proprietary active chemicals, which, because of their hydrophilic nature, react with water and cement particles in the concrete to form calcium silicate hydrates, increasing the density of the CSH phase, and/or pore-blocking precipitates in the existing micro-cracks. The mechanism is analogous to the formation of CSH and the resulting crystalline deposits become integrally bound with the hydrated cement paste, thus contributing not only to a significantly increased resistance to water penetration but also to the healing of the existing damages and cracks.
This paper summarizes the results of a wide experimental investigation jointly performed by Politecnico di Milano (Italy), Indian Institute of Technology Madras, Chennai (India) and Universitat Politecnica de Valencia (Spain) to assess the effectiveness of different commercially available crystalline admixtures on the self-healing capacity of cement based materials.