Dynamic response of walls and slabs by single-degree-of-freedom analysis—a critical review and revision

Single-degree-of-freedom (SDOF) methods for dynamic analysis of reinforced concrete flexural members subjected to blast or ground-shock loading are reviewed. It is concluded that the Equivalent single-degree-of-freedom method is an appropriate approximate method of analysis, but that the widely published parameters in common usage for two-way spanning members such as slabs and walls are inaccurate by up to almost 50% for some coefficients, due to inappropriate assumptions and approximations being used in their original derivation. Revised values of SDOF parameters are presented for two-way spanning members, based on modern finite element and yield-line calculations.