DIMENSIONING OF THE MAIN BRACKET FROM CONCRETE I PREMADE OF A MANUFACTURING FACILITY

Shinasi ZEJNELI , Berat ZEJNELI

Abstract

Purpose: The development of small and medium-sized enterprises in the private sector as imperatives of the time for the construction of low buildings but with large spaces for the needs of small non-polluting industries in different environments, the demand of investors in the private social sector is the construction of the above-mentioned buildings but with large spaces for the needs required by the design task imposes the preparation of the main supports with large dimensions, in this paper the principle of dimensioning and calculation of beams up to 30m, which cannot be prepared with these dimensions in factories, is presented for the production of prefabricated products, but the one must be prepared in the place where the construction of the building-object takes place since the beam with a length of 30 m cannot be transported due to inadequate road infrastructure. Methods: Dimensioning of the beam - the main supports for a space of 30m with prestressed concrete brand MB 30, MB 40, MB 50, MB 60 and with prestressing class 0.6; 0.8; 1.0 where the solution with the approximation method is used. Dimensioning of the Rigel-beam constructive element is done for cable prestressing, determination of the method for: - Filling-incorporation of concrete -Type of soft armor - The time of advance - Load according to the purpose of the object, the place where the construction takes place (altitude) - The part of the beam where the load is more pronounced, larger - the most unfavorable position - Shear forces in different cuts, at the beginning of the beam in the middle and other places. - Necessary measurements of honors, deformations, reductions, loss of prestressing seal about time, etc. -Parameters and geometric indicators of transverse and longitudinal sections. Design: Analysis of the most meritorious cross-section of the Rigel-beam Results: Results for the brands of prestressed concrete mentioned above, results for normal values, results from checking values indirectly (Fizo zone), results of reinforcement for acceptance of values from the tensile force, checking the coefficient of safety against fracture, control of tangential parts, value from the calculation of reinforcement in the area of application of the prestressing force, value - results from the calculation of deformations, the weight of the beam and the amount of material and details. Conclusions: After the dimensioning of cross-sections with different heights h=150cm, h=160cm, h=170cm, h=180cm with brands MB 30, MB 40, MB 50, and MB 60 for the same loads, it was found a conclusion of a beam with a height of h=180cm is acquired as the most meritorious for the given area, with cross-section "I", with the geometric characteristics given in the work, and with the mechanical characteristics, cable routing, loss of prestressing force and many other values that are necessary for this type of prestressed concrete beams.

Pages: 216 - 228