Stability analyses and design recommendations for practical shoring systems during construction

This paper presents stability analysis and design recommendations for the falsework of wood and metal post shores. Based on the setup of shoring systems used on actual construction sites, analysis models of the shoring system have been derived. The experimental test results indicate that the base stiffness to the ground of shores is 50 t-cm/rad for (490 kN-cm/rad) wood post shores and 70 t-cm/rad (686 kN-cm/rad) for metal post shores of which the joint stiffness between members is 750 t-cm/rad (7,355 kN-cm/rad). With these stiffnesses, factors of 0.75 for wood post shores and 0.85 for metal post shores are used to modify the critical loads of shoring systems calculated from individual shores. The critical loads of a shoring system increase with the number of fixed strong shores, but are not affected by the number of leaning columns. In simplifying shore design, the LeMessurier formula is used for the strength computation of shoring systems composed of wood post shores. The critical loads of shoring systems increase linearly with the number of strong shores, but they are invariant with the positions of strong shores. If the required number of strong shores is defined, the critical loads of shoring systems can be found by interpolation.