A new procedure for the analysis of construction loads in multistory reinforced concrete structures

Abstract

Construction loads in a multistory reinforced concrete building are largely influenced by the construction schedule. These loads may exceed the designed strength of the building's structure or produce early cracking of the floor, with adverse consequences to its service conditions, because of amplifications of time-dependent deflections. Fresh floors are supported by previously cast floors, using a formwork system with shores and reshores. The definition of floor loads, considering the construction sequence, provides an outlook of the load history on the structural elements from the beginning to the end of the construction work. Models for evaluating that phenomenon are very important and, as far as possible, should be simple and suitable for quick analysis. The present work proposes a new method to analyze the distribution of construction loads. This method is based on the experience of the authors in using finite elements in sequential structural analyses of multistory reinforced concrete buildings. Using the concept of primary structures, the new method offers a viable way of distributing construction loads between the formwork and the interconnected floors. the forms were removed, each floor bears only its self-weight. Loads on shores and reshores are evaluated by equilibrium.Operation 10 involves the fifth floor casting, whose weight is equally divided among the four floors of the supporting system. Note that their load factors increase by 0·25. Equilibrium conditions lead to the updating of shore and reshore load factors.

Load transmission between slabs and shores during the construction of RC building structures – A review

“…Table 1 contains a summary of all the proposed calculation methods formulated up to the present time. [36] 1952 Sweden Grundy & Kabaila [37] 1963 Australia Taylor [47] 1967 Australia Liu et al [48] 1986 USA Aguinaga & Bazant [49] 1986 Spain-USA Mosallam & Chen [40] 1991 USA El-Shahhat & Chen [50] 1992 USA Duan & Chen [41] 1995 USA Beeby [43] 2001 UK Fang et al [51] 2001 China Prado et al [53] 2003 Brazil Kajewski [54] 2005 Australia Fang et al [52] 2009 China Park et al [55] 2011 South Korea Calderón et al [46] 2011 Spain Buitrago et al [59] 2016 Spain Buitrago et al [60] 2016 Spain…”