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  • Author: Florin Toma x
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Abstract

The Near Real-Time System for Estimating the Seismic Damage in Romania, implemented in 2012 at the National Institute for Earth Physics, is one of the automated systems that can directly contribute to saving many lives right after a major earthquake, by translating earthquake parameters into damage probabilities for different areas within Romanian counties and showing emergency intervention necessities, and can also lead to mitigation actions before an earthquake, through raising awareness and highlighting vulnerable aspects of the building stock and economic and social impacts.

This paper aims to present the scientific background of this constantly upgrading system, and to show different results for relevant scenarios, for intermediate-depth Vrancea earthquakes and other crustal earthquakes. Several important questions are tried to be answered, like: “How credible are the estimated losses?”, “What are the most vulnerable aspects?” or “How can the damage maps be useful for authorities?”.

Currently, the system uses for building loss estimation the analytical methods (as the Improved-Displacement Capacity Method - I-DCM) implemented within the open-source software SELENA (SEismic Loss EstimatioN using a logic tree Approach), together with HAZUS methods for estimating the human casualties. The building stock is defined through 48 different capacity and fragility curves, depending on construction material, height and age. As hazard data, PGA and SA values obtained through the ShakeMap System and based on real recordings and attenuation relations are used. The area currently analyzed by the system consists of 19 Romanian Counties, capital Bucharest and 9 regions in northern Bulgaria; resolution of the data is at administrative unit (commune or city) level. We aim to provide an insight of each part of this system, justify the choices made and also discuss the improvement possibilities.

Abstract

This work is an attempt viewing to emphasize the possibility of using waste - as aggregate - from the demolition of silicoaluminuous refractory linings for manufacturing concrete with aluminuous cement. The article shows further on the possibilities of reducing the cement dosage and of using cheap admixtures.

Abstract

The paper is an attempt to present and evaluate of the some monolithic refractory materials, originating from our research activity, with potential to be used as the thermoprotective linings for the nonferrous metals and ferrous alloys manufacturing installations in foundries and steelworks.

Abstract

Iris reticulata is one of the most appreciated flower species, being found in both field crops and greenhouse cultures. Our research has as a major objective the study of the influence of particularities of thermic regime from cold period upon the quality of the bulbs flowering. For planting we used bulbs distributed in three equal batches, for each batch, differentiating the period of cold necessary for the rooting of the bulbs. The cold period was provided in three variants: in the refrigerator (5°C), in a shade which climate similar to the outside (5°C), in the cellar (10°C). The introduction of bulbs planted in the greenhouse for forcing was performed for each of the three batches after 4, 6 and 8 weeks of cold storage. The microscopic preparations show that on begin of cold period all the floral elements are formed inside in the bulb. The best quality of the bulbs flowering was obtained on the variants which cold period occurred on the shade, at °5 C temperature.

Abstract

Refractory concretes with the usual cement content (about 20%) present, besides their well-known advantages, several important disadvantages which make such concretes unfit for certain applications. The relatively high CaO content in concretes, the presence of even small amounts of SiO2 and Fe2O3 in cement reduce in the first place the concretes refractoriness; if their relatively high porosity is also taken into account, the concretes behavior is further damaged in regard to the structural and thermal-chemical stability. especially at their high operating temperatures. This work is an attempt to correct the shortcomings shown by reducing the cement dosage and using appropriate admixtures in the technological process of concrete making.

Abstract

The paper shows data related to coexistence of various binding systems, which could be present during the hardening of special concretes. It is taken into account the Ultra Low Aluminous Cement Concretes additivated with different materials (phosphates and mineral ultra dispersed powders - Condensed Silica Fume, Hydrated Alumina etc). In correlation to the pH-value, these substances can favour the forming of new binding systems besides the hydraulic binder (which is not important in this case). The new system is the coagulation binding form. The coagulation binding system has a very important role in the advanced compactness and in the increasing mechanical strengths of concrete structures.