提高地基动力刚度是减小高科技设施环境振动的有效措施。而水泥注浆是提高地基动力刚度的行之有效的工程技术之一。基于原位振动扫频试验,以5~100 Hz、步长为0.5 Hz的简谐激励作为动力荷载,通过测量和对比注浆区域和非注浆区的地面振动响应,研究了水泥注浆改性卵石土对地面振动的衰减作用。试验结果表明,水泥注浆改性卵石土能够降低29.5%的竖直向地面振动速度总有效值和30.8%的东西向地面振动速度总有效值,而对南北向地面振动速度总有效值几乎没有影响。此外,在整个分析频率范围内,水泥注浆改性卵石土的振动衰减作用是不连续的,表现为有些频率地面振动的速度有效值得以衰减而有些频率地面振动的速度有效值得以放大,但是总体而言衰减作用大于放大作用。
Abstract
Improving the dynamic stiffness of subgrade soil is an effective measure to reduce the environmental vibration at high-tech facilities. Cement grouting is one of the effective engineering techniques to improve the dynamic stiffness of subgrade soil. Based on in-situ frequency sweep vibration test in which harmonic excitations at 5 to 100 Hz with steps of 0.5Hz were used as dynamic loading, the reduction effect of cement-improved gravel soil on ground vibration was investigated by measuring and comparing the ground vibration responses at the cement grouting area and the non-grouting area. The test results show that the cement-improved gravel soil can reduce the total root mean square velocity of the vertical ground vibration by 29.5% and the total root mean square velocity of the east-west ground vibration by 30.8%, but has little effect on the total root mean square velocity of the north-south ground vibration. In addition, the vibration reduction effect of the cement-improved gravel soil is discontinuous in the whole analyzed range of frequency, namely the root mean square velocities of ground vibrations at some frequencies are reduced and at others are amplified. However, overall, the reduction effect is greater than the amplification effect.
关键词
环境振动 /
高科技设施 /
扫频试验 /
水泥注浆 /
振动衰减
{{custom_keyword}} /
Key words
environmental vibration /
high-tech facility /
frequency sweep test /
cement grouting /
vibration reduction
{{custom_keyword}} /
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] Kim HS, Kang JW. Smart platform for microvibration control of high-tech industry facilities[J]. International Journal of Steel Structures, 2017, 17(1):155-164.
[2] 马蒙,刘维宁,丁德云,等. 地铁列车振动对精密仪器影响的预测研究[J]. 振动与冲击,2011,30(3):185-190.
MA Meng, LIU Wei-ning, DING De-yun, et al. Prediction of influence of metro trains induced vibrations on sensitive instruments[J]. Journal of vibration and shock, 2011, 30(3):185-190.
[3] 贾宝印,楼梦麟,宗刚,等. 车辆荷载引起地面振动的实测研究[J]. 振动与冲击,2013,32(4):10-14.
JIA Bao-yin, LOU Meng-lin, ZONG Gang, et al. Field measurements for ground vibration induced by vehicle [J]. Journal of vibration and shock, 2013, 32(4):10-14.
[4] Nelson JT. Recent developments in ground-borne noise and vibration control[J]. Journal of Sound and Vibration, 1996, 193(1):367-376.
[5] Jayawardana P, Achuhan R, De Silva GHMJS, et al. Use of in-filled trenches to screen ground vibration due to impact pile driving: experimental and numerical study[J]. Heliyon, 2018, 4(8):e00726.
[6] Garinei A, Risitano G, Scappaticci L. Experimental evaluation of the efficiency of trenches for the mitigation of train-induced vibrations[J]. Transportation Research Part D: Transport and Environment, 2014, 32(303-315.
[7] Woods RD. Screening of surface waves in soils[J]. Am Soc Civil Engr J Soil Mech, 1968, 94(4):951-979.
[8] 孙晓静, 袁扬, 马蒙,等. 地铁列车运行引起远场低频振动响应预测研究[J]. 振动与冲击,2017,36(4):198-202.
SUN Xiao-jing, YUAN Yang, MA Meng, et al. Prediction of metro train-induced low frequency vibration responses in far field[J]. Journal of vibration and shock, 2017, 36(4):198-202.
[9] Salyards KA, Iii RJF. Review of generic and manufacturer design criteria for vibration-sensitive equipment[C]. Proceedings of the IMAC-XXVII. Orlando, Florida USA, 2009.
[10] Gao G, Chen J, Yang J, et al. Field measurement and FE prediction of vibration reduction due to pile-raft foundation for high-tech workshop[J]. Soil Dynamics and Earthquake Engineering, 2017, 101:264-268.
[11] Sanayei M, Anish KP, Moore JA, et al. Measurement and prediction of train-induced vibrations in a full-scale building[J]. Engineering Structures, 2014, 77(oct.15):119-128.
[12] Amick H, Wongprasert N, Montgomery J, et al. An experimental study of vibration attenuation performance of several on-grade slab configurations[C]. SPIE Proceedings. Bellingham, WA, 2005.
[13] Neuenschwander RT, Liu L, Marques SR, et al. Engineering Challenges of Future Light Sources[J], 2016.
[14] Persson P, Persson K, Sandberg G. Numerical study on reducing building vibrations by foundation improvement[J]. Engineering Structures, 2016, 124:361-375.
[15] Persson P. Analysis of vibrations in high-tech facility[D]. Lund, Sweden: Lund University, 2010.
[16] 王晋芳. 既有建筑地基注浆加固应用研究[D].石家庄: 石家庄铁道大学,2019.
[17] 吴顺川, 金爱兵,高永涛. 袖阀管注浆技术改性土体研究及效果评价[J]. 岩土力学,2007,28(7):72-77.
WU Shun-chuan, JIN Ai-bing, GAO Yong-tao. Studies of sleeve-valve-pipe grouting technique and its effect on soil reinforcement[J]. Rock and Soil Mechanics, 2007, 28(7):72-7.
{{custom_fnGroup.title_cn}}
脚注
{{custom_fn.content}}