COMPARATIVE ANALYSIS OF LIMIT BEARING CAPACITY OF A CONTINUOUS BEAM APPLYING THE LIMIT AND SHAKEDOWN ANALYSIS DEPENDING ON THE CHARACTER OF THE LOAD

Applying the theorems of structural limit analysis it is possible to determine the limit load of linear systems exposed to load which increases proportionally until the formation of failure mechanism. In the case when beam systems are exposed to repeated load, the limit theorems do not yield the adequate solutions, thus the adaptation theorems which made safe limit load determination possible were developed simultaneously. In this paper, applying the static and kinematic theorem of limit and shakedown analysis, the failure load of continuous beam with two spans has been determined. Also displayed is the difference between the values of failure forces depending on the character of load and the beam span value in order to assess justification for application of the shakedown method in the analysis of the limit bearing capacity of the beams.Original Abstract: Primjenom poucaka analize granicne nosivosti moguce je odrediti granicno opterecenje linearnih sustava izlozenih opterecenju koje se proporcionalno povecava dok ne dode do loma. U slucaju kada su nosivi sustavi izlozeni ponovljenom opterecenju, postavke granicne analize ne daju odgovarajuca rjesenja. Zbog toga su simultano razvijeni adaptacijski poucci koji su omogucili sigurno odredivanje granicnog opterecenja. U ovom je radu odredeno opterecenje loma kontinuiranog nosaca s dva polja, primjenom statickog i kinematickog poucka granicne analize i metode adaptacije. Pokazana je takoder razlika izmedu vrijednosti sila loma ovisno o karakteru opterecenja i vrijednosti raspona nosaca da bi se procijenila opravdanost primjene metode adaptacije u analizi granicne nosivosti nosaca.