In accordance with Sect. 6.6.3.1.1 and Sect. 10.14.1.2 out of the ACI 318-19 and CSA A23.3-19 respectively, RFEM effectively takes into consideration concrete member and surface stiffness reduction for various element types.
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Technical Article: Concrete Stiffness Modification in RFEM 6 According to ACI 318-19 and CSA A23.3-19
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