Field-test for environment vibration induced by shield tunneling in sand gravel layer
TAO Lian-jin1,GUO Fei1,HUANG Jun2,LI Ji-dong1,AN Jun-hai1
1.The Key Laboratory of Urban Security and Disaster Engineering, Ministry of Education, Beijing University of Technology, Beijing 100124, China;
2. CCTEB civil defense and Underground Space Institute Wuhan 430071, China
The sand gravel layer in Beijing western region are of characteristics of shallow burial depth and large particle size. Environment vibration influence induced by shield construction in sand gravel layer is great. Field tests of acceleration vibrations were carried out in an interval tunnel of Beijing. Vibration data in construction process had been simultaneously collected by buried strata points, ground points and measuring points in tunnel. Vibration frequency domain characteristics and spatial attenuation law were drawn. Environmental influence assessment was conducted. It is shown that the vibration is mainly due to collision with cutter tool and gravel particles. Vibration caused by machines and transport vehicle have little effect on ground environment. Main frequency of vibration near cutter head is mainly distributed in more than 30 Hz. The main frequency of measuring point away from cutter head about 40 m on the surface cross-section has decayed to below 20 Hz. Amplitude of measuring points are related with relative position between cutter head and measuring points, which are in order as followed: points ahead of the cutter head, points on both sides of the cutter head, points behind the cutter head. Vibration level in vertical near the cutter head on ground is about 80 dB, it has decayed to 60 dB away from cutter head between 20 m to 30 m.
[1] New B M. Vibrations caused by underground construction [M]. London:Proceedings, Tunnelling’82, 1982:217-229.
[2] 王汝恒, 贾彬, 邓安福,等. 砂卵石土动力特性的动三轴试验研究[J].岩石力学与工程学报,2006(S2):731-736.
WANG Ru-heng, JIA Bin,DENG An-fu, et al. Dynamic triaxial testing study on dynamic characterisistics of sandy pebble soil[J]. Chinese Journal of Rock Mechanics and Engineering,2006(S2):731-736.
[3] 郭文,李强,王汝恒. 振动频率对饱和砂卵石土动模量和动阻尼比影响的试验研究[J]. 四川建筑科学研究,2007, 33(6): 113-115.
GUO Wen, LI Qiang, WANG Ru-heng. Experimental study on influence of vibration frequency to dynamic modulus and damping ratio characteristics of saturate sandy pebble soil[J]. Sichuan Building Science,2007, 33(6): 113-115.
[4] 黄清飞. 砂卵石地层盾构刀盘刀具与土相互作用及其选型设计研究[D].北京:北京交通大学,2010.
[5] GB10071-1988,城市区域环境振动测试方法[S].
[6] 叶茂, 任珉, 谭平,等. 城市交通诱发地面振动测试时域分析[J].环境科学与技术,2011,34(S2):201-205.
YE Mao, REN Min, TAN Ping,et al. In situ measurement and analysis for environmental vibration induced by urban traffic in time domain[J].Environmental Science Technology, 2011, 34(S2):201-205.
[7] 王济,胡晓. MATLAB 在振动信号处理中的应用[M]. 北京:中国水利水电出版社, 2006.
[8] 葛哲学,沙威. 小波分析理论与MATLAB R2007实现[M].北京:电子工业出版社, 2007.
[9] ISO Standard. ISO2631/1: Mechanical Vibration and shock-evaluation of human exposure to whole body vibration-Part1: General requirements [S]. Washington D. C.: ISO Standard, 1997.
[10] ISO Standard. ISO2631/2: Mechanical vibration and shock-evaluation of human exposure to whole body vibration -Part2: Continuous and shock induced vibration in buildings (1-80 Hz) [S]. Washington D. C.ISO Standard, 1989.
[11] GB10070-1988,城市区域环境振动标准[S].