Shaking table test of buried pipelines under longitudinal non-uniform excitation

The seismic response of buried pipelines under longitudinal uniform and non-uniform excitations was investigated to explore the similarities and differences of soil and pipeline seismic responses in different boxes by employing the multi-point shaking table tests. The test data of soils and pipelines in different boxes were analyzed and studied in terms of acceleration and pipeline strain. The results show that:(1) The displacement time-history curves of the soil surfaces in different boxes are similar under uniform excitation with different loading levels. Under non-uniform excitation, however, the displacement time-history curves of the soil surfaces in different boxes are significantly different. Obvious longitudinal relative displacements occur between the soils in each box, the soils are torn apart, and large residual displacements are produced after ground motions. (2) Compared with the uniform excitation, there is obvious relative displacement between the pipelines and the surrounding soil under the non-uniform excitation, which results in the increase of the pipeline strain with a peak value about twice that under the uniform excitation. (3) Under uniform excitation, the seismic responses of the pipelines are similar to the response of the soil. Under the non-uniform excitation, the seismic responses of soil and pipeline in different boxes are different, but the seismic response laws of soil and pipeline in each box are basically the same. © 2022, Science Press. All right reserved.