摘要
为了研究高架桥梁桥墩爆破引起的振动传播规律及其对周边的影响,采用现场试验和数值分析相结合的方法开展相关研究。首先在表层无混凝土的土层上选取有代表性的桥墩,按相同尺寸和配筋在试验场进行浇注,修建2个独立墩柱模型进行单柱爆破试验及现场实测;然后利用LSDYNA软件建立单柱数值计算模型,对爆破试验进行了详细的拟合分析,给出了各测点的振动速度时程曲线及其频谱曲线,并从振动幅值和频谱特性2个方面分析了爆破振动效应;最后将计算结果与试验结果进行对比分析。研究结果表明:随着测点与爆源之间距离的增加,各方向速度响应逐渐衰减,其中竖向速度衰减最快,测点各方向速度为0.05~1.36cm/s,其中竖向速度最大,水平切向速度最小;各方向振动频率为15~20Hz,与周边一般建筑的基频相差较大,爆破振动在空气中衰减迅速,表明爆破自身引起的振动效应影响较小;数值拟合分析结果与试验结果的动力响应规律基本一致,表明采取的动力有限元计算分析方法能较好地模拟爆破过程,可利用该方法对整个高架桥的爆破过程进行初步分析,从而为最终的爆破方案提供合理依据。
To research the vibration transmission law and its effect on surroundings induced by viaduct pier blasting,the field test and numerical analysis were combined to carry out relative research.Firstly,representative piers were selected on the surface of soil without concrete,which were poured at the test site according to the same size and reinforcement.And two independent pier column models were built to carry out single column blasting tests and field measurements.Then,numerical calculation models were established through LS-DYNA software and the detailed fitting analysis of the blasting test were conducted to obtain vibration velocity curves and their spectrum of each measuring point.Blasting effect was analyzed from two aspects,vibration amplitude and spectral characteristic.Finally,the results were compared with the test data.The results show that the velocity response of each direction decreases graduallywith the increase of distance between measuring point and blast source.The vertical velocity decays fastest,and velocity at each point is between 0.05 to 1.36cm/s,among which the vertical velocity is the largest and the horizontal tangent is the smallest.The vibration frequency at each point in each direction ranges from 15 to 20Hz,has relatively large difference to the fundamental frequency of general buildings in surrounding area.Blasting vibration decreases very quickly in air,which indicates that the vibration effect caused by blasting is less affected.The numerical fitting analysis results are basically consistent with the dynamic response of the test results,which verifies that the dynamic finite element method employed in this paper can better simulate the test process,and can be used for preliminary analysis on the whole blasting process of viaduct,so as to provide reasonable basis for blasting scheme.
作者
王国波
胡俊
季杉
谢伟平
王礼
WANG Guo-bo HU Jun JI Shan XIE Wei-ping WANG Li(Key Laboratory of Hubei Province for Road, Bridge and Structure Engineering, Wuhan University o{ Technology, Wuhan 430070, Hubei, China School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan 430070, Hubei, China)
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2017年第4期105-111,共7页
Journal of Chang’an University(Natural Science Edition)
基金
国家自然科学基金项目(51178365)
关键词
桥梁工程
足尺模型试验
爆破
振动响应
动力有限元
bridge engineering
full-scale model test
blasting
vibration response
dynamic finite element
