There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

2004아테네 올림픽대회출전 한국레슬링 대표선수의 무산소성 운동능력 및 등속성 근력

Vitruvius The Ten Books On Architecture

Using recycling materials in construction is a safe way for achieving sustainability. Although European policy, through directives given, supports their use and coherent research results derive from the scientific society, their use in practice is limited. It is generally accepted that the use of alternative construction materials with low environmental impact and of low cost is an important issue. As a part of the integration in sustainable development approach, the eco-friendly materials present a great interest in building construction manufacturing. Towards this direction, many studies have been focused on the exploitation of natural fibers as reinforcements in building materials. This study is an attempt to add more experimental results by the use of bio-fibers to building materials in order to ensure the performance of recycled materials such as bio-fibers in the construction sector. Three types of natural fibers jute, coconut and kelp were used as additives in 1.5% by mortar volume. Their role in cement and lime mortars was recorded by testing mechanical, physical and microstructure properties. The results indicate that natural fibers act in favor of strength and durability. Nevertheless, bio-fibers work differently in strong cement mortars in relation to the “soft” lime-based materials. Advantages can be gained in both cases but certain aspects should be taken into account such as the adhesion to the mortar matrix and the water content of the mixture.

Natural fiber-reinforced mortars

https://run.unl.pt/bitstream/10362/13505/1/RI16%20-%20Matias%20et%20al_manuscript_Lime%20mortars%20with%20ceramic%20waste%20-%20A%20review_CBM%2073_2014_125-136.pdf

Lime mortars with heat treated clays and ceramic waste: A review

Analysis of ancient mortars and design of compatible repair mortars: The case study of Odeion of the archaeological site of Dion

Grouting is an old and widely used irreversible technique for consolidating historic masonries. However, since some undesirable secondary problems appeared in historic masonries after interventions with cement-based grouts, alternative mixtures have been also studied. In the paper, traditional binders such as hydrated lime, pozzolan, clay and brick dust have been used as constituents of grout mixtures, which were modified with cement and admixtures. Grouts’ performance was tested in fresh (Fluidity, Penetrability, Volume Stability) and hardened state (Dynamic Modulus of Elasticity, Flexural and Compressive strength). Results showed clearly that grouts based on traditional binders present adequate performance and strength, for filling discontinuities and consolidating masonry structure. Proper combinations of “soft” binders, aided by small proportions of cement and admixtures developed 28-d and 90-d strength of 2.5 and 5 MPa respectively.

Experimental study on the performance of lime-based grouts used in consolidating historic masonries

Performance of lime-based mortars at elevated temperatures

Structural mortars and plasters from cisterns and baths (thermes) from Roman, Byzantine and Ottoman period in Greece are analyzed in terms of their physico-mechanical, chemical, and microstructural characteristics, in order to find the key factors for their functionality. From the analysis it is found that their coherent and dense structure is due to the action of different mechanisms caused by the selection and combination of raw materials and the interaction with the special environment into which they served. The binding system is mixed, with the combination of hydrated lime and materials with pozzolanic properties. The aggregates are both siliceous and brick fragments of different granulometry, according to the mortar’s type (structural or plaster). The raw materials used as binders and aggregates and the technology practices during mortar application contribute to low porosity mortars with dense structure. Additionally, the environment of the cisterns and baths functioned on the benefit of the materials, as it favored the dilution of the calcite and the secondary phases formed in the mortars’ porous nature assisted towards the cohesiveness of their structure. The technology used for the production of mortars applied in baths and cisterns for a long period of time proves the high knowledge of materials’ behavior in order to produce durable constructions, resistant to highly deteriorating factors.

Vasiliki Pachta

Papers

Analysis of ancient mortars and design of compatible repair mortars: The case study of Odeion of the archaeological site of Dion

Experimental study on the performance of lime-based grouts used in consolidating historic masonries

Performance of lime-based mortars at elevated temperatures

Analysis and characterization of hydraulic mortars from ancient cisterns and baths in Greece

Evaluation of inclusions in mortars of different historical periods from greek monuments