Shore overloads during shoring removal

Abstract The considerable overloads originating during the shore removal process can affect the structural safety of a multistory concrete building under construction. With an incorrect shoring removal reversal of stresses may occur which can cause concrete cracking and excessive deflections. Moreover, excessive overloads will damage the falsework, producing important economical losses due to its elevated cost. A measured program has been conducted during the shore stripping at different building levels. Results show that in general the Refined Method is adequate in a conservative form for the shore removal procedure. Then, the influence of different parameters such as concrete strength or steel reinforcement in shore removal overloads was studied. The use of the actual concrete strength and modeling the steel reinforcement produces a more accurate theoretical result. Nevertheless, these considerations do not bring major changes (less than 4%). Finally, shore overloads originating in five different shore removal procedures in a typical structure have been compared, establishing some criteria for a safe shore stripping sequence. For example the best stripping procedure found consists of removing shores by rows.

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