考虑施工过程影响的PCCP地震响应分析

为了研究地震作用下施工过程对预应力钢筒混凝土管(PCCP)的影响,建立考虑PCCP施工过程影响的非线性有限元模型,利用生死单元技术实现PCCP从地应力平衡到施加预应力钢丝预应力、铺设管道,再到回填回填土过程的有限元分析,以压实度作为衡量回填土施工质量的指标,基于黏弹性人工边界理论、等效节点力地震动输入法以及静-动力边界...

Seismic response analysis of PCCP considering the effects of the construction process

In order to study the impact of the construction process on the prestressed concrete cylinder pipe(PCCP)under the action of an earthquake, a PCCP seismic response analysis method considering the impact of the construction process is proposed: a nonlinear finite element model that considers the impact of the PCCP construction process is established and the alive and death element technology is used to realize the finite element analysis of the PCCP from the ground stress balance to the application of prestressed steel wire prestress, pipe laying, and backfilling to determine the degree of compaction. As an index to measure the construction quality of backfills, based on the viscoelastic artificial boundary theory, equivalent nodal force ground motion input method and static-dynamic boundary conversion method, the analysis considers the construction process and the impact of different backfill compaction quality on the PCCP seismic response analysis. The results show that the stress of the pipeline is affected by the gravity of the backfill and itself. The hoop compressive stresses of the inner and outer concrete pipe tops, the outer units of the pipe bottom, and the inner units of the pipe waist are larger considering the influence of the construction process than those of the pipe top without considering the construction process. The hoop compressive stress of the inner unit of the tube bottom and the outer unit of the tube waist is smaller than the construction process without considering the construction process; under the the earthquake, the backfill soil is evenly compacted, and increasing the compression degree of the backfill soil can reduce the axial tensile stress at the PCCP socket. The more uneven the degree of backfill compaction, the greater the maximum value of the horizontal and vertical rotation angles between the pipes, and the impact of the backfill compaction quality on the vertical rotation angle is greater than the impact on the horizontal direction.