THEORY AND CALCULATION OF ROAD BRIDGES BURIED ABUTMENTS BASES

Buried abutments are most broadly applied in connections of road bridges structures and approach embankments. Embankment and cone weight force influence is the peculiarity of buried abutments bases and foundations constructions conditions of stability and deformation. There is in the article a description of road bridges buried abutments bases engineer calculation method including the complex of limit state checkings and grounding of calculation schemes. The calculations fulfil by calculated schemes of hard-plastic midst theory (on the base of prof. G.M. Shakhunjantc horizontal strengths method) and linear deformation (or elastic-plastic) midst theory. Table data necessitated for calculations are quoted. A way for define the strains in buried abutments bases from cone and approach embankment by the linear deformation midst theory is elaborated by means of making conventional (equivalent) calculated scheme. Non-weighting layer is added to the base, acting load is substitute by equal by value half-endless strip. By it on the real level of base arise normal and tangent strains, conformed with the form approach embankment restricted by slopes from three sides. It is suggested a method of buried abutment base soils stability calculation by the More-Coulomb equation, realizing by mean of strains, obtained in accordance with above descripted way.

Furniture use safety at early design stage

Furniture use safety at early design stage. This paper presents a virtual method of determining the usage safety of a bed frame. The aim of the study was to investigate the influence of different external loads dictated by standards on the newly designed bed structure. Furthermore, it was decided to take into consideration unusual ways of acting load. Finally, the test of dynamic load was carried out. The analysis was executed by means of Finite Element Method in Computer Aided Engineering software. Results of stress distribution and displacements were compared to previously investigated mechanical properties of the used materials, such as elastic plywood and pine wood rigidity. Based on compared data, the safe use of bed frame was determined. The numerical calculations performed proved that there are possibilities of design changes to improve user safety and/or reduce production costs while ensuring sufficient mechanical properties of the furniture. Conclusions of the analysis suggested a possibility to sub-optimize the tested solution.

On the Eccentrically Loaded Socket Footings With Cut - Off Pyramid Shaped Socket

In this work considerations concerning eccentrically loaded socket footing with cut-off pyramid shaped socket were presented. As an object of study sloped footing with 1.40 m height, corresponding to the maximum frost depth has been adopted. Knowing that in practice there are no perfect pure axial loads, load applied on the eccentricity has been taken into considerations. Eccentric loads result in footing rotation in the direction of eccentricity and acting load, hence one footing end is imbedding into the ground, whereas second end tries to rise up. To observe that phenomenon, elastic type of support under the foundation was introduced corresponding to the naturally humid sand with medium compaction. Presented in this paper considerations of innovative connection technology between footing and column were based on performed numerical studies. Advantages and disadvantages of presented footing in comparison to normal socket footings solutions were widely discussed. Numerical analyses were performed with the utilization Finite Element Method based SolidWorks software.

Creep and Long-Time Strength of Compression Elements from Foam Concrete

In this article discusses the mechanical properties of foam concrete, which submitted based on the experimental data of long force resistance and deformation of compression elements from foam concrete. Also submitted criterion range of strength and deformation characteristics of foam concrete different structural modification with taking into account the permanently acting load, which necessary for calculation and design structures of buildings. In article such characteristics of foam concrete as durability and deformability at the age of 28 days by results of short-term tests and also influence of average density and a type of structure on its durability and deformability are considered. Change of mechanical properties of foam concrete in time by results of short-term tests is analyzed and studied. Experimental and theoretical researches which have in turn allowed to recommend for rationing of value of settlement characteristics the foam of concrete taking into account their variability, aging and duration of action of loading are executed.

Distributed Sensing of Loads Acting Against the Hull of a Stationkeeping Vessel in Ice

This paper introduces the concept of distributed motion sensing for stationkeeping vessels in ice infested waters. During the SKT 2017 project, conducted in February and March 2017 in the Bay of Bothnia, five inertial measurement units were installed on the vessel Magne Viking. Four of the sensor units were installed at different positions inside the hull of the vessel, which enabled the system to locally measure ice-induced vibrations in the hull of the vessel. The fifth sensor unit was installed at a central position of the vessel and served as reference sensor for measuring the acting global load on the vessel. Under stationkeeping the global load measured on the ship should be close to zero, because the environmental load is equal to the force from the stationkeeping system. However the remaining four motion sensor units in the hull also measured locally induced vibrations. The study shows that this sensor configuration allows for the detection of changes in the acting load against the vessel. This is demonstrated with motion data obtained during the stationkeeping trials on the vessel Magne Viking.

Influence of long-term compressive stresses on strength of concrete and steel-fiber concrete prismatic element

The strength and deformation characteristics of concrete and steel-fiber concrete on prisms and cubes are determined. Short-term and long-term tests of the samples were carried out taking into account the recommendations of the regulatory documents for the testing of concrete. Loading of samples with a long load was carried out in force installations (stands) consisting of four metal rods to which rigid loading plates were fixed at certain levels with threaded connections. To cover the entire operational spectrum of the stress state of real reinforced concrete elements, levels of 0.3; 0.4; 0.5; 0.67 and 0.8 from the short-term destructive load were adopted as long-term loading levels. All samples, which were more than a year under the action of a long-acting load, increased their bearing capacity. Prisms from steel-fiber concrete, which were under the influence of a long-acting load during 370 days, increased the bearing capacity, depending on the level of load, by 30-50%. The higher load level, the higher the creep rupture strength. When the loading was repeated before the destruction, the deformations of steel-fiberconcrete prisms changed linearly.

Analysis of Power of Underwater Cylinder Excited by Propeller/Shaft System

To adopting means to reduce power radiated from the hull, power injected by the shaft system and that radiated by the hull are analyzed for an underwater cylinder excited by the propeller/shaft system. As the power is injected by combination of the solely acting loads on the junction and there concurrent, power transmitted by each solely acting load, radiated by the hull and the concurrent power are compared to understand the mechanism of power transmission and transformation. In the comparisons, quantities are decomposed according to circum orders to understand the radiation modes. The conclusion drawn in the paper will provide some guidance for acoustic reduction by shaft isolation design.

Research on Load Analysis and Calculation Method of the Unit Glass Curtain Wall

Due to the applicable installation height, small mass, flexible characteristic, large span, so the unit glass curtain wall (UGCW) could be differ from the glass curtain wall of frame members. Based on the characteristic of UGCW, analysis the load of UGCW and building the formula of static wind load, Earthquake Action, Temperature Function etc. The formula to calculate the load of the unit glass curtain wall (UGCW) is given on the base of analyzing the acting load and the mechanism of force transfer of the UGCW in service condition. Hope to provide some reference for similar designs.