Title:
Construction safety of multistory concrete buildings
Author(s):
Ashraf M. El-Shahhat, David V. Rosowsky, and Wai-Fah Chen
Publication:
Structural Journal
Volume:
90
Issue:
4
Appears on pages(s):
335-341
Keywords:
concrete construction; deflection; loads (forces); shoring; multistory buildings; reliability; safety; structural analysis; Construction
DOI:
10.14359/3974
Date:
7/1/1993
Abstract:
This paper investigates the issue of safety of multistory concrete buildings during construction. The safety of the structure, in these early days of its life, is greatly influenced by a large number of factors, including the loads, the geometry, material properties of the building, and the method of construction. For a building constructed at a fast rate, in which the shoring and reshoring system is employed and the partially stiffened concrete slabs are used frequently as load-carrying elements during construction, the safety of the building becomes an important issue for investigation. The failure of the building may be taken to correspond to the failure of the concrete slabs. The corresponding limit state functions for a reliability analysis are characterized by the flexural bending, punching shear, and excessive deformations. In the reliability analysis, the loads and resistances (strengths) are treated as random variables. The structural analysis of the building is performed using the "improved" method (El-Shahhat and Chen) in which the deflection approach is used to compute the load effects of the building during construction. The method is used to analyze the building at all stages of construction and to identify the critical stage corresponding to the maximum probability of failure. The failure probability is computed using Monte Carlo simulation. A parametric study is performed to investigate the effect of concrete strength, spacing of forms, and the construction cycle length on the construction safety.