USE OF MODELS TO PREDICT THE DYNAMIC RESPONSE OF DYNAMICALLY LOADED UNDERGROUND STRUCTURES

摘要

Similitude requirements for predicting the dynamic response of under- ground structures are investigated, and the validity of the proposed model design conditions is checked experimentally. The structures used in the tests were hollow aluminum cylinders instrumented with SR-4 strain gages. Most of the tests were run on circular cylinders having diameters of 4 in., 2 in. and 1 in. Some data are also presented for structures having square cross sections. In all tests the structures were buried in dry Ottawa sand. Three different types of loaders were used in the test program: a drop-weight loader, a vertical shock tube, and a horizontal shock tube. Peak strain and complete strain-time curves were obtained for various depths of burial and a detailed analysis of the data is presented. For the one series of tests performed with the horizontal shock tunic consistent data were obtained and a discussion of the discrepancies encountered is presented. Several series of tests were completed with the drop-weight loader and the vertical shock tube.