The constant need for recycling, waste prevention and general environmental protection represent the new directive approaches imposed by the geo-political, industrial and environmental context, at the regional, European and global level. Ensuring the environmental protection and reducing the natural resources consumption represent general purposes of the sustainable development and also considerations to implement the Circular Economy Model [1]. The present study is developed with respect to the previously mentioned principles: the waterjet cutting operations by the use of abrasive GARNETs for quality, speed and accuracy gain, are in continuous expansion, generating proportionally increasing wastes, which could be valorized by innovatively integrating them in advanced cementitious materials for the construction industry. The international research regarding the use of abrasive waterjet Garnet wastes as raw material for construction industry are at incipient stage and quite limited, but preliminary results are promising. Further studies are presently developed, considering the potential benefits and also the reduced toxicity degree of abrasive Garnet wastes. This paper offers a general overview concerning the recent studies performed in the topic of efficient use of abrasive Garnet wastes in different building materials. Supplementary, further research, both theoretical and experimental is considered, for developing green, advanced, high performance cement-based materials by using the abrasive waterjet Garnet wastes, mainly as fine grain addition or replacement in the composites.

SH-FECM (Fibre Engineered Cementitious Materials with Self-Healing capacity), developed at NIRD “URBAN-INCERC” Cluj-Napoca Branch in the last five years, are consistently based on Engineered Cementitious Composites (ECCs) concept, elaborated in the early nineties at Michigan University (USA). They all represent a cement-based typology of dispersed reinforcement composites able to develop high deformability by the means of multiple cracking pattern under loading, leading to a cumulative set of valuable material features: metal like behaviour when subjected to loads, brittle failure prevention, increased self-healing potential via the compositional design, etc. The process of development and constant improvement of the SH-FECMs represents a long term theoretical and experimental approach, aiming to establish the optimum raw materials (mostly locally available) compatibility within the cementitious matrix so that the composites would present superior performance under comparative evaluation. This paper presents the first results, evaluated as positive for both, fresh and hardened state materials, regarding the inclusion of Slurry Lime (SL) addition as replacement of the initial lime powder addition (L) in the material composition. The long-term effects are on ongoing investigation, but the initial results are clearly promising, starting from a better fresh state aspect and evaluating for faster setting time and improved early age mechanical behaviour. The beneficial effects are also in terms of economic and ecological aspects, considering that the used lime slurry (SL) addition represents an actual waste resulted from a local, natural stone processing factory. Its use as direct addition in the SH-FECMs mixtures could represent an efficient recycling and waste prevention action, with long term beneficial potential, in terms of Circular Economy principles.

The continuing hydration of unhydrated cement grains was proven to be one of the most important processes for promoting the self-healing effect within cementitious composites, by generating the CSH gels as valuable healing products, not only sealing the microcracks but also being able to provide some mechanical recovery of the material, as well [1]. It was also concluded that the process slows down in time, being strongly connected to concrete age. In order to ensure the continuous hydration potential for the cementitious materials, also as essential self-healing (SH) promoter, the addition of reactive grains is considered. This paper presents preliminary aspects regarding the possibility of polymeric encapsulation of some reactive grains and the feasibility of the concept in terms of matrix compatibility to the addition and also their SH performance under induced, controlled cracking. The considered self-healing addition behaves intelligent as it would react with water only when the cracking occurs, creating gaps in the waterproofing coating. The object of this research is less focused on regaining the mechanical characteristics of concrete, like pre-cracking strength, but mainly on preventing aggressive agents from entering in the concrete mass and aggressing the reinforcement.

Developing a non-destructive method which delivers fast, accurate and non-invasive results regarding the concrete compressive strength, is an important issue, currently investigated by many researchers all over the world. Different methodologies, like using the simple non-destructive testing (NDT) or the fusion of different techniques approach, were taken into consideration in order to find the optimal, most suitable method. The purpose of this paper is to present a new approach in this direction. The methodology consists in predicting the concrete compressive strength through ultrasonic testing, for non-destructive determination of the dynamic and static moduli of elasticity. One important, basic assumption of the proposed methodology considers values provided by technical literature for concrete dynamic Poisson’s coefficient. The air-dry density was experimentally determined on concrete cores. The dynamic modulus of elasticity was also experimentally determined by using the ultrasonic pulse velocity (UPV) method on concrete cores. Further on, the static modulus of elasticity and the concrete compressive strength can be mathematically calculated, by using the previously mentioned parameters. The experimental procedures were performed on concrete specimens, namely concrete cores extracted from the raft foundation of a multistorey building; initially they were subjected to the specific NDT, namely ultrasonic testing, and the validation of the results and the proposed methodology derives from the destructive testing of the specimens. The destructive testing is generally recognized as the most trustable method. The precision of the proposed method, established with respect to the destructive testing, revealed a high level of confidence, exceeding 90% (as mean value). It was noticed that even the cores with compressive strength outside of mean range interval (minimum and maximum values) presented high rate of precision, not influencing the overall result. The high rate of accuracy makes this method a suitable research background for further investigations, in order to establish a reliable NDT methodology which could substitute the very invasive and less convenient, destructive method.

The entry into force of Romanian Code P 100-3 / 2009 (updated in 2019) regulating the expertise of existing, seismically vulnerable constructions requires the assessment of the seismic performance of structures having the structure of structural masonry. The code also applies to the assessment of historical heritage buildings. The Evangelical Cathedral in Sibiu (in German Evangelische Stadtpfarrkirche) is one of the oldest and most impressive Gothic buildings in Transylvania (Romania).The building is dominated by the 7-level tower, with four turrets on the corner of the roof, a sign that the city has a right to condemnation (in Latin and Gladiers, literally "the right of the sword").According to the requirements of normative P 100-3 "Evaluation and design code of the consolidation works on existing buildings, seismically vulnerable" in chapter 4.4.3.-Materials, are presented in-situ investigation methods for such constructions. The tests will be in terms of the factors of confidence in the knowledge levels of type: KL2 -normal knowledge and in the category KL3 -complete knowledge. From the point of view of the level of inspection and testing, the tests fall into the category of limited type tests.