No abstract

This study aims to emphasize, by means of a comparative study, the efficiency of some damper systems as modern variants of consolidation / seismic structural safety enhancement used for buildings with reinforced concrete structure designed and erected according to the P13-type standards (from 1963) and considering this as an alternative possibility instead of retrofitting with reinforced concrete jackets (with significant implications for most of the structural elements at all levels of buildings). Damper devices are elements that can be easily replaced later in case of damage. Case studies were made, based on structural calculations in the linear elastic field, using the ETABS program.

The safety of railways has been and remains a critical topic. Whether it is infrastructure or rolling stock, the issue of safety is a permanent concern of the utmost importance, being reflected in the efficiency of any transport system. This paper focuses on the safety in operation of pressure vessels that equip railway tanks. There are many articles and works on this subject, and it is well-known that there are both national and international regulations regarding their design, execution, operation and maintenance. Also, there are quite a few reports on the BLEVE (Boiling Liquid Expanding Vapour Explosion) phenomenon resulting in material damage and significant casualties. The BLEVE-type explosion is not considered a chemical explosion derived from a gas-air explosive environment (also present in non-flammable gases), but rather a mechanical explosion through over-pressurization. Thus, we propose a comparative study between the results obtained using theoretical methods and those obtained as a result of tensoresistive measurements on such a tanker.

In the process of preparing cement or asphalt concrete – frequently used in ways, roads and access road construction, it is necessary to sort out poly-dispersed granular mixtures from bilge deposits or quarries. The mechanical sieving performs the separation of the granules on dimensional sorts (the size of graded grains can be 1... 70 mm) by means of machines called screeners. In the case of vibrating screeners, the working body (the sieve) presents a vibratory movement that ensures a high productivity of the screening machine and a very good quality of the final products obtained. The article studies the productivity of the vibrating screen used in mineral aggregates sorting process obtained by different methods. In this regard, a pragmatic simplified formula called Pragma is proposed, a formula which was tested with good results in situ experiments done on a bi-mass vibrating screen in a pilot station.

Nowadays the pollution is a stringent and critical problem that imposes serious measures to be taken into account. Water is one of the most important medium factors that facilitate the pollutants transport with serious consequences on the environment. There are many significant sources of water pollution which can affect the human health and may damage seriously the fauna and flora. The paper asserts the main sources of Danube's pollution with heavy metals and proposes some solutions in decreasing the amount of these pollutant elements. The area of study that offered the data in this paper was the SomovaParcheş aquatic complex, considered to be representative from the pollutant elements point of view. This area is located between Tulcea and Isaccea, in the pre-deltaic area of Danube Delta Biosphere reservation. Water is an medium factor, compulsory and crucial for everyday life, being the most outspread element on Earth. In nowadays situation, Terra finds itself in a critical period of its life from the pollution point of view and from the struggle for environmental protection point of view.