Tom 22 (2020): Zeszyt 1 (December 2020)

In this study, it is presented a multicriterial approach of the automatic management techniques of industrial installations using wastewater. This has an extremely positive effect on the economical results of the entire irrigation and wastewater equipment. Choosing the automatic management by a neural networks system is the result of several stages of analysis, modelling and simulation of hydrodynamic processes that take place within the wastewater installation on each equipment and in its integrity. The study exposes an analysis and offers a solution of automatic management of the installation of irrigation using wastewater.

The study presents an analysis of the sediment thickness compared with bathymetric and geophysical settings in the Bay of Bengal and Andaman Sea, Indian Ocean. It uses a combination of the high-resolution data: topographic GEBCO, satellite and marine gravity anomalies, EGM2008 geoid and GlobSed to visualize the correlation between relief, gravity and trends in continent-ocean sediment transport. The results include thematic maps and 3D model showing increased sediment thickness in the Bengal Fan (8,0 to 8,2 km) in NE direction with maximum in Ganges Fan (16,2 km), and southward decrease in the Andaman Sea from Irrawaddy river mouth (6-7 km) to the Strait of Malacca (1-2 km). All maps and 3D model have been plotted by Generic Mapping Tools (GMT) cartographic scripting toolset version 6.0.0.

The term of shear lag is related to the discrepancies between the approximate theory of the bending of beams and their real behaviour. It refers to the increases of the bending stresses near the flange-to-web junctions and the corresponding decreases in the flange stresses away from these junctions. In the case of wide flanges of plated structures, shear lag caused by shear strains, which are neglected in the conventional theory, may be taken into account by a reduced flange width concentrated along the webs of the steel girders. In EN 1993-1-5, the concept of taking shear lag into account is based on effective width of the flange which is defined in order to have the same total normal force in the gross flange subjected to the real transverse stress distribution as the effective flange subjected to a uniform stress equal to the maximum stress of the real transverse distribution. Some aspects concerning the shear lag phenomenon and a working example for a box girder of a heavy crane runway to illustrate the determination of the shear lag effect are also presented.

This paper presents several theoretical issues regarding the behaviour and calculus of the connections made with end plates and bolts, including the cover plate for the tensile stress flange. An example for calculating the hybrid connection solution is also provided, when end plates are joined together with bolts and an additional cover plate over the joint area, at the elongated flange of the girder, a solution applied for a bridge for which the feasibility study was performed.

Sustainable development and sustainable construction present every firm with new challenges. The concept of sustainability is the new driving force for the firm and decision making, which are part of the overall sustainable strategy. The implementation of this strategy is a factor for creating, offering and realizing additional economic, social and environmental value for the client, stakeholders and society as a whole, and building competitive advantages. Detailed knowledge of the principles and requirements for sustainability and the necessary changes at the market and company level are mandatory for every construction manager. The main goal of the research is 1) analysis of the role of the construction market and the firm for sustainable development and sustainable construction, 2) outlining the necessary changes in the organization and management of the firm in order to create sustainable construction firm and development sustainable construction.

In the last years questions related to sustainable development are particularly relevant. The construction market is usually identified as the first sector to face serious problems and requires special attention in implementing the idea. The main reasons for this assessment lie in the specifics of construction as an economic activity, the specifics of the construction product, the construction process, the specifics of organization and management of the construction company and the strong economic, social and environmental effect. The purpose of the proposed study is: 1) analysis of the problem of sustainability of the construction market, 2) the role and influence of the government for the development of sustainable construction.

This paper presents a research that has been done on two types of stainless steels, one of Spanish origin and the other of Romanian origin. Both Spanish and Romanian stainless steels have been subjected to several tests, regarding the influence of vibrations on their mechanical properties and their welding behavior. The samples were made of welded stainless steels. They were subjected to a thermal hardening treatment at a temperature of 950 degrees, with a holding time of 4 hours in the presence of mechanical vibrations. Then comparative tests were performed on both stainless steels at: hardness, tensile test, resilience, microstructural analysis and determination of the longitudinal modulus of elasticity. The research has shown a reduction of the thermo-mechanically influenced area, which contributes to the achievement of a high quality welded joints.

The research performed and presented in this paper, aims to verify the welding behavior of electrodes developed experimentally, as well as the possibility of their use in production. A group of two electrodes produced by Bohler Company, Gridur 24 and B.M.N were taken as reference, in order to compare them in terms of the mechanical properties of the deposited metal, with the experimentally developed electrodes EICr12Fe and EIMn13SiFe. They were made determinations of the chemical composition of the deposited metal with the two types of electrodes, measurements regarding the hardness of the metal deposited, comparative determinations of the structure of the weld deposit, and of the welding penetration, determinations of the deposition yield and verification of the welding behavior.

The paper presents a constructive version of a mechanical vibration generator designed to be used at stress relieving of welded joints. This installation can be used on all brands of steels and welded joints, whether they have magnetic properties or not. In the generator construction a DC motor was used, in order to be able to adjust the speed more easily. The speed adjustment is made with a potentiometer, and the speed measurement is made with a tachometer. The tachometer measures the speeds based on the pulses given by a four-pointed cam rotating between the plates of a capacitor. The vibration system also contains a piezoelectric accelerograph, which is attached to the welded part subjected to vibration, in order to measure the level of vibration and the parameters of the vibration wave.

In this article we present the way how to create a program in the Scilab-Xcos environment with which it can be dimensioned, mathematically modeled and simulated a water pumping installation.

The mathematical equations implemented in the program with which the dimensioning and simulation are done are presented.

Fuzzy logic was used to generate the pump characteristics.

This paper presents comparative analysis by mathematical modeling and simulation of two thermal systems for hot water production consisting of solar collectors and storage tank with and without inbuilt heat exchanger. Thermal hot water systems use solar radiation as the source of energy, and mathematical models of their simulation are developed in Scilab-Xcos. An example of simulation of these thermal systems is also presented in this paper.

Macroporous lands sensitive to wetting represent a category of sites with high vulnerability during construction exploitation. In this regard an effective measure is the protective shielding measures against the main factors influencing its behavior. The paper deals with a complex case study by both its importance functions and the fact that the objective analyzed is a part of historical monuments of particular value to the local community, namely the water tower in Braila Public Garden - România.

The present work was carried out with the aim of knowing the characteristics and the management made of the agropastoral dams of the commune of Gogounou which are of a great utility for the local populations. To do this, twenty (20) dams were chosen according to the strategic interest that they present for the population, that is to say a polling rate of 87% on all the dams of the municipality. An inventory of the dams was made according to quantitative and qualitative indicators. The results showed the existence of (04) groups of dams according to the technical characteristics and some qualitative variables. The parameters that lead to the degradation of these dams are often related to the age and type of dam and the place of installation. Groups (2 and 4) are agropastoral dams (100%) and more than half of the dams are on flood sites. Results have also shown that there are management committees around all the dams in the commune of Gogounou, but which are mostly non-functional at almost 75%. Also, it has been found that the breeders are mostly transhumant and sedentary who use (100%) dams for watering animals. This cohabitation between farmers and pastoralists does not occur without major conflicts, in particular, that of land whose settlement is generally peaceful. In short, the management of the dams in the commune of Gogounou is a real challenge to be met for a better development, both economically and socially to guarantee the prosperity of the actors and prepare them to adapt to the vagaries of the climate future.

Within this paper, a methodology for assessing the flood risk was developed by extracting the essential factors that favor the generation of flood risk. These factors, that had a sufficient number of data for a proper comparative analysis, are: potentially affected population based on population density, total agricultural area, total built-up area and the historical maximum amount of precipitation recorded in 24 hours. The flood risk assessment is presented in the form of indices calculation for all these factors and maps generated which representing the results of the calculation of the above-mentioned factors and the results of the flood risk index calculation.

Urban floods have particularities that must be presented in detail to understand the flood phenomenon, which is why this paper takes into consideration these areas. In order to determine the probability of urban floods, all disturbing factors that may affect the urban area must be taken into account.

The method presented in this paper can be used in sectoral planning activities and integrated planning studies, and for damage assessment.