Innovative materials and techniques for the conservation of 20th century concrete-based cultural heritage

Project Information

InnovaConcrete

Grant agreement ID: 760858

DOI

10.3030/760858

Project closed

EC signature date 13 December 2017

Start date 1 January 2018

End date 31 December 2021

Funded under

• INDUSTRIAL LEADERSHIP - Leadership in enabling and industrial technologies - Advanced materials

Total cost

€ 6 916 287,50

EU contribution

€ 6 882 086,50

Coordinated by

UNIVERSIDAD DE CADIZ
Spain

Periodic Reporting for period 2 - InnovaConcrete (Innovative materials and techniques for the conservation of 20th century concrete-based cultural heritage)

Reporting period: 2019-07-01 to 2021-12-31

Summary of the context and overall objectives of the project

Modern architecture is directly related to the Portland cement and reinforced concrete in the end of the 19th Century. It generated a complete revolution in construction techniques, promoting the use of fair-faced concrete during the 20th Century. In this context, it is easy to understand the evolution of concrete production showing an increase of nearly 1700% in 100 years. The common employment of fair-faced concrete, without coatings or paintings, increases its susceptibility to decay. The earlier manifestation of most decay processes is the onset of micro-cracks that is followed by a decrease in mechanical performance. In addition to these phenomena, reinforced concrete is specially affected by the ingress of water containing pollutants, which may cause corrosion of the reinforcements. Unlike traditional building materials, conservation methodologies for historic concrete reparation and long-term maintenance are less advanced due to its little recognition as part of our Cultural Heritage. Thus, 20th Century historic concrete is currently at risk from a lack of appreciation and care.
InnovaConcrete project addresses all challenges previously raised because its ambitious plan is not only focused on the development of advanced materials and techniques for historic concrete conservation but also aiming to better understand, define, interpret and manage 20th century concrete Cultural Heritage for future generations. Thus, the project objectives were set according to a holistic approach which includes: (i) the development of innovative conservation products and techniques, specifically designed for historic concrete. (ii) Establish an informed revision of historic concrete conservation policies based on significance, pathologies, treatments… (iii) Raise awareness of concrete heritage among citizens and institutions. (iv) Market uptake of the developed technologies (validation, standardization, exploitation strategies...)

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

Nine innovative impregnation products especially designed to preserve the historic concrete have beendeveloped. The synthesis of these new products has been guided with support of modelling tools. A new family of impregnation treatments which are able of sealing micro/nano-cracks by producing C-S-H gel, responsible for the mechanical properties of cement paste, have been developed. The alkoxysilane-based formula produces C-S-H gel by the polymerization of silanol groups with Ca+2 ions existing in the cement pore water. A product containing Ca oxalate was developed to improve compatibility with carbonatic materials.
A second step was to integrate innovative performances to the C-S-H technology, producing multifunctional treatments. Firstly, corrosion inhibitors responsive to external stimili (pH & Cl-) were integrated. Secondly, multifunctional products with superhydrophobic properties have been obtained. An atmospheric plasma device was also developed as an alternative. InnovaConcrete has also explored the advantages to use cementitious coatings reinforced with halloysite nanotubes. Finally, InnovaConcrete has investigated a biotechnology based approach to produce enzyme-assisted self-healing of damage concrete by exploiting the naturally residing bacteria on historic concrete.
The laboratory validation of the InnovaConcrete technologies has been performed in more than 1000 concrete and mortar samples representative of common building pathologies and material properties (including mock-ups from case studies). Complementary to this experimental study, a powerful multi-scale model simulating concrete degradation has been developed. The validation experiments were used for the fine optimization of the products.
In situ validation of the InnovaConcrete technologies has been performed on 8 case studies, being one of them completely restored. These case studies have been selected to cover a wide range of societal/economic impacts as well as to represent different environmental conditions and conservation problems.
Regarding to second target of InnovaConcrete, to promote awareness about concrete heritage. The first step consisted of the selection of the significant concrete-based monuments in Europe. A final selection of 100 monuments was made according to the adopted criteria. The complete information is available in an open platform (https://100of20.innovaconcrete.eu/).
In addition, the first benchmark guidance document for the conservation of concrete heritage has been implemented. This document provides guidance for the conservation of concrete heritage with respect to its cultural, historical aesthetics and technological significance. Complementarily, a tool for touristic and commercial potential analyses of concrete cultural heritage has been developed integrated in a web-based decision making tool.
On the other hand, more than 100 different dissemination, citizen awareness and training activities have been organized, including several outside the EU territory. These activities include 9 workshops around the case studies. Moreover, other cultural events, targeted for general public, were organized such as phographical exhibitions and contests. All these activities produced a huge expectation from the local media. 5 virtual tours around the case study with the possibility to get relevant information about the monuments have been also designed
Finally, according to the third target, the market uptake of the innovative solutions, an InnovaConcrete product has already launched to the market, one is under negotiation with a partner company and all technologies reach a TRL 6+. Addtionally, the social-economic analysis tools led to launch of a spin-off consulting company (ITEch-Heritage & Welfare)

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The InnovaConcrete project has applied nanoscience to develop advanced materials and techniques specifically designed for concrete heritage preservation. Impregnation treatments, producing, in situ, C-S-H gel, multi-purpose treatments giving rise to additional superhydrophobic or corrosion inhibiting performance and enzyme-assisted self-healing have been successfully developed.
Moreover, InnovaConcrete has thoroughly committed to the relevance of historic and artistic issues in “historic concrete” preservation. Thus, the study of criteria of the authenticity and the evaluation of the concrete-based CH are significant activities of the project. In recent years, many concrete masterpieces have already been demolished because they have not been considered to be elements of heritage. Therefore, InnovaConcrete works as watchdogs of concrete heritage. The project also promoted the creation of social-economic activities around “historic concrete”. In addition, the first benchmark guidance for the conservation of concrete-based heritage has been published as part the InnovaConcrete results, and its content along with a socioeconomic analysis app has been implemented as a decision making tool to be employed for conservation actions on historic concrete.

Rome Workshop-Aula Nervi

Concrete surface protection

InnovaConcrete Selected Case Studies