Experimental validation of ASME strain-based seismic assessment methods using piping elbow test data

Abstract

To quantify the conservatism of existing ASME strain-based evaluation methods for seismic loading, this paper presents very low cycle fatigue test data of elbows under various cyclic loading conditions and comparison of evaluation results with experimental failure cycles. For strain-based evaluation methods, the method presented in ASME BPVC CC N-900 and Sec. VIII are used. Predicted failure cycles are compared with experimental failure cycle to quantify the conservatism of evaluation methods. All methods give very conservative failure cycles. The CC N-900 method is the most conservative and prediction results are only ∼0.5% of experimental data. For Sec. VIII method, the use of the option using code tensile properties gives ∼3% of experimental data, and the use of the material-specific reduction of area can reduce conservatism but still gives ∼15% of experimental data.