摘要
以陕西一电厂粉煤灰库区下部基岩内埋设的输水隧洞为对象,研究上部粉煤灰坝填筑碾压振动过程中下卧浅埋隧洞的动力响应特性。通过ADINA有限元软件建立隧洞衬砌结构的动力分析模型,采用峰值振动加速度作为评价指标分析下卧隧洞的频谱特征和加速度反应谱特征,拟合隧洞设计加速度反应谱曲线。结果表明,碾压振动作用下隧洞的加速度反应频率主要分布在12Hz以下的较窄范围内,表现为多峰状不规则形态;隧洞顶点的加速度反应谱卓越频率集中在0.01~0.02s的短周期范围内;粉煤灰库区内的振动频谱曲线主频集中在低频范围内,与软土的低通滤波作用相吻合,这为坝体施工控制及隧洞安全性评价提供了依据。
Taking the water conveyance tunnel buried in the lower bedrock of the fly ash reservoir area of a power plant in Shaanxi Province as an object,the dynamic response characteristics of the underlying shallow tunnel during the rolling vibration of the upper fly ash dam were studied.The dynamic analysis model of the tunnel lining structure was established by ADINA finite element software.The peak vibration acceleration was used as the evaluation index to analyze the spectrum characteristics and acceleration response spectrum characteristics of the lower tunnel,and the tunnel design acceleration response spectrum curve was fitted.The results show that the acceleration response frequency of the tunnel under the action of rolling vibration is mainly distributed in a narrow range below 12 Hz,showing a multi-peak irregular shape;The excellent frequency of the acceleration response spectrum of the tunnel apex is concentrated in the short period range from 0.01 to 0.02 s.The main frequency of the vibration spectrum curve in the fly ash reservoir area is concentrated in the low frequency range,which is consistent with the low-pass filtering effect of soft soil.The research results can provide a basis for dam construction control and tunnel safety evaluation.
作者
韩婧文
张爱军
胡锦方
HAN Jing-wen;ZHANG Ai-jun;HU Jin-fang(College of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,China)
出处
《水电能源科学》
北大核心
2021年第6期101-104,共4页
Water Resources and Power
基金
国家自然科学基金项目(51978572)
陕西省重点研发计划项目(2017ZDXM-SF-074)。
关键词
灰坝
碾压振动
隧洞
频域分析
加速度反应谱
ash dam
rolling vibration
tunnel
frequency domain analysis
acceleration response spectrum
