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The present paper approaches of plates subjected to transverse loads, when the shear force and the actual boundary conditions are considered, by using the Finite Element Method. The isoparametric finite elements create real facilities in formulating the problems and great possibilities in creating adequate computer programs.

Some considerations concerning the design of the paraboloidal suspended roofs are made. The main geometric aspects are first time presented. For the roofs we propose, as pattern, the equivalent continuum membranes, and the efforts in the cable are determined by using the membrane efforts and their equations. Two examples are analyzed: elliptic paraboloide and hyperbolic paraboloide, with horizontal projection under the form of an ellipse.

Retaining walls are large category of engineering structures of multiple uses, having an essential safety ensuring role. The structural systems are varied because the situations and requirements derived from both site conditions and other criteria are varied. The paper enlarges upon retaining walls systems that use an outstanding amount of precast units and multiple cylindrical vault type structural systems supported by abutments [1], [2]. The paper proposes extending the structural system to retaining walls and develops certain specific issues. Some considerations regarding structural design are made.

Mohr’s theory concerning the stress limit state and its use in determining the active and passive soil pressures on retaining walls is being developed. Rankine’s hypothesis, according to which the pressures on surface elements that are parallel to the free surface of ground have a vertical direction; the horizontal acceleration effect which generates inertia forces in the soil are accounted for. On these grounds the normal and tangential stresses on planes parallel to the back – of – wall ground surface are being expressed. By using the intrinsic curve corresponding to the sliding and the stresses expressed on these planes, Mohr’s limit circles, as well as the active and the passive pressures generated by the seismic event on the retaining wall are determined. The solving process is an essentially graphic one and allows for the finding of the sliding plane and the main normal stresses as well as the extreme tangential ones in the points of this plane in which the tension state has reached the limit.

General numerical methods based on the discretization of the surface between structure and soil in finite elements are developed and, by their help, the stiffness matrix is determined. There are considered the medium model of linear elastic, homogeneous and isotropic half-space and anisotropic half-space, respectively. In case of rigid structures or with rigid base, it is essentially for their response evaluation to know the stiffness coefficients.

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the results obtained regarding the realization of a functional model of equipment for managing in-depth amendments on salted lands and the results regarding the effect of the work performed in three soil conditions. At the same time, the physical properties of the amendment used (phosphogypsum), determined in laboratory conditions, in order to know the problems that may occur during the application work, are presented. [ABSTRACT FROM AUTHOR]

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article describes the results of long-term research on the dynamics of vanadium migration in water, bottom sediments, higher aquatic plants, bottom invertebrates, and fishes in the cooling reservoir of the Moldovan Thermal Power Plant. An obvious dependence of the level of vanadium in aquatic ecosystem on the quantity and composition of burnt fuel at the plant was established. In most of cases the migration of vanadium in the system “water – silts” occured from water layers to bottom sediments. But if the intensity of sulphate reduction and putrefaction processes increases and the concentration of dissolved oxygen decreases the reverse diffusion from silts to water will become possible. The level of accumulation of metals in hydrobionts is one of the most important parameters in the biomonitoring of metals in aquatic ecosystems. The concentration of vanadium in aquatic plants and animals depended on the intensity of metabolism and interspecific features, plastic and generative metabolism (at fish), but in the same time reflected the dynamics of vanadium in the environment. The values of the coefficient of vanadium biological accumulation in aquatic organisms reached up to n×107