The holistic approach of SINCERE integrates advanced materials and techniques, ensuring both structural integrity and energy efficiency. By embracing innovation in restoration, we preserve the past while building a sustainable and resilient future.

Self-healing

Self-healing concrete, typically incorporating the healing agent in the cement matrix, is designed to autonomously repair microcracks, increasing the durability and the lifespan of structures while reducing maintenance costs.

Encapsulated healing agents represent an innovative technology designed to enhance the longevity of structures, while concurrently minimizing the environmental footprint of the construction industry. This groundbreaking solution focuses on the utilization of cement-based macro-capsules, with a diameter ranging between 2-5 mm. These capsules are crafted using the pan-coating technique, featuring a composition comprised of a cement core covered with a durable and dense shell made by hydrated cement.

The capsules are incorporated into mortars and concrete mixtures by substituting an equivalent volume of sand. Following the hardening of the mixture and upon the appearance of cracks, the core of the capsule is revealed. In the presence of water within the crack, the cement present in the core reacts with water, initiating the process of filling the cracks with cement hydration products. Ultimately, after the sealing of the crack with the hydration products, the crack is sealed, and the matrix as well as the reinforcement are protected.

Introductory reading:
Belle et al. (2018). A Review of Self-Healing Concrete for Damage Management of Structures. Advanced Materials.
Technical publication:
Papaioannou et al. (2022). Synthesis and integration of cement-based capsules modified with sodium silicate for developing self-healing cements. Construction and Building Materials, 316(7). Elsevier.

Phase Change Materials (PCMs)

Phase Change Materials (PCMs) in cement mortars aim to regulate temperature fluctuations in buildings by absorbing and releasing heat during phase transitions, thereby enhancing both the energy efficiency of the structure and the thermal comfort of the indoor environment.

PCMs are an alternative to generating systems with latent heat storage capacity. SINCERE explores diverse PCMs, with temperature ranges covering a wide spectrum of climates, so that the retrofitting of historic buildings with modern architecture in various regions and countries can be effectively carried out. Sustainable materials will also be considered as components of these PCMs and their optimal integration into the binder matrix including novel materials with low CO2 emitting cements will be pursued. An adjustment and optimization of these formulations will be carried out using the necessary additives to regulate the rheology and the final properties of the material.

Introductory reading:
Patil et al. (2023). A review of the thermal storage of phase change material, morphology, synthesis methods, characterization, and applications of microencapsulated phase change material. Journal of Polymer Engineering.
Technical publication:
Rubic-Aquinaga et al. (2023). Enhancement of Latent Heat Storage Capacity of Lime Rendering Mortars. Historic Mortars International Conference.

High Performance Fiber Reinforced Cementitious Composites (HPFRCC)

High Performance Fiber Reinforced Cementitious Composites (HPFRCC) stand out as remarkable materials with tensile-hardening properties, exhibiting post-cracking tensile strength equal to or surpassing that of an un-cracked cross-section. This distinctive characteristic empowers designers to consider its tensile strength in structural calculations, thereby enabling the utilization of advanced computational methods to streamline the optimization process and foster the creation of innovative structures.

In specific applications, the inclusion of fibers in HPFRCC can serve as a viable alternative to traditional rebars, offering advantages such as the elimination of the need for a concrete cover and the avoidance of intricate rebar cage construction.

HPFRCC, distinguished by their capacity to deliver tailored and multifunctional performance, stand out as a valuable asset for the construction industry. They can be utilized in the construction of new structures and components, but also serve as an ideal retrofitting/upgrading layer for structures undergoing renovation. Looking ahead, the potential of HPFRCC holds particular promise in the realm of structural retrofitting for historic buildings. This involves enhancing load bearing and deformation capacity, transitioning from a brittle diagonal cracking mode to a failure mechanism characterized by the ability to diffuse localized damage into the subgrade through multiple fine cracks. These enhancements not only fortify durability of the building, but also extend the lifespan of the repair.

Introductory reading:
Liberato Ferrara (2019). High performance fibre reinforced cementitious composites: Six memos for the XXI century societal and economical challenges of civil engineering. Elsevier.

Textile Reinforced Concrete (TRC)

Textile-reinforced concrete (TRC) aims to enhance the mechanical properties of traditional concrete by incorporating textile materials, providing increased tensile strength, flexibility, and durability to the construction material.

TRC is a sustainable concrete which allows a reduction of the concrete consumption of constructive elements (columns, walls, etc.), diminishing the embodied energy (EE), and embodied carbon (EC). The technology combines high strength concrete with textile fabrics, which are usually made of alkali-resistant glass (AR-glass), carbon or basalt yarns that are weaved or knitted together. The textiles are characterized by high tensile strength, high resistance to corrosion and good deformability. The high corrosion resistance of the textiles eliminates the need for massive concrete coverage, which ultimately reduces the total amount of concrete and enables constructing concrete elements with less material and weight. The deformability of textiles enables the production of modular and complex shapes of concrete elements that are difficult to produce by using conventional steel bars reinforcement. These qualities enable to construct light and durable concrete elements that can be used as a preferable alternative to the traditional concrete construction technology.

Introductory reading:
Peled et al. (2017). Textile Reinforced Concrete. CLC Press.

Hempcrete

Lime-Hemp Concrete (LHC), also known as Hempcrete, is an innovative sustainable building insulation material based on bio-aggregates made of hemp shives, mixed with lime binder.

Hemp shives are a major by-product of the hemp fibers industry, accounting for ~70% of the hemp plant's mass. The embodied carbon (EC) of LHC is negative, due to the carbon sequestration of the hemp plant through photosynthesis during its growing period, as well as the carbonation process of lime. Furthermore, LHC possesses low thermal conductivity due to hemp shives' high porosity. As a result, it has the ability to diminish the fluctuations of both temperature and relative humidity within the building, as compared to the outdoor ones. LHC's ability to improve the thermal comfort within the building allows a reduction of the operational energy (OE), and operational carbon (OC) of the building.

Introductory reading:
Ahmed et al. (2023). Hemp as a potential raw material toward a sustainable world: A review
Technical publication:
Haik et al. (2023). Lime Hemp Concrete with Unfired Binders vs. Conventional Building Materials: A Comparative Assessment of Energy Requirements and CO2 Emissions . Energies, 16(2).