预应力蛋形消化池振动台试验研究

分别输入不同加速度峰值的El-Centro波和广州人工波,对1:8缩尺的预应力蛋形消化池模型进行了模拟地震振动台试验研究。对模型试验结果进行了加速度、位移、应变反应分析,并与有限元模型计算结果作了对比。发现在试验过程中,空池模型和半池水模型主要处于弹性阶段,局部有非线性反应出现;充水导致结构的基频降低;充水对中腹部以下壳体与对中腹部以上壳体产生相反方向的影响;不同的地震波输入对结构反应产生不同的影响,广州人工波下的结构反应较之输入相同加速度峰值的El-Centro波为大;有限元模型的计算结果与试验结果吻合较好。研究结果表明预应力蛋形消化池具有良好的抗震性能,三维流固耦合有限元分析模型以及时程分析计算方法是合理、可行的。

An experimental study on prestressed egg-shape digesters

The seismic performance of prestressed egg-shaped digesters(PESD) is studied.A structural model of a 1/8 scale was designed and tested on the shaking table with two earthquake peak accelerations,namely the El Centro and artificial Guangzhou earthquakes.The acceleration,displacement and strain responses were analyzed and compared with the results from FEM modeling.It is found that the half-full model and the empty model mainly assume linear-elastic behavior with only localized non-linear effects.The filled water has apparently reduced the natural frequency of the PESD.The coupling interaction between water and the shell enhances the responses below the middle plane and reduces the responses above the middle plane of the model.Different seismic excitations have distinct influences on the responses of the PESD because of the fact that different frequency spectra and the amplification factors under GZR excitation are greater than those under El-Centro excitation.The calculated results of FEM model agree well with those of the shaking table tests.The results indicate that PESD has good seismic resistances and the FEM model appears to give both rational and reasonable predictive results.