Influence of free surface numbers on the energy distribution and attenuation of vibration signals of underwater drilling blasting
-
摘要: 针对自由面不仅影响爆破效果还影响爆破振动效应的问题,提出从能量角度探索自由面对水下爆破振动衰减规律的影响。以三峡大坝至葛洲坝水利枢纽河段水下钻孔爆破地震波现场监测数据为基础,结合SPH-FEM数值模拟技术和小波时频能量分析方法,对不同自由面数量的爆破振动信号的总能量、各频带间的能量分布特征及振动衰减规律进行了研究。结果表明:水下钻孔爆破具有低主频、短持时、快衰减的特点,爆破主频带主要集中在15.625~31.250 Hz;受单一自由面限制的水下开槽爆破,监测信号的爆炸能量主要以振动形式消耗,单自由面比振动能为13.14 mm2/(kg·s2),随着后续开挖爆破自由面数量的增加,双自由面和三自由面的比振动能分别降低至1.36和0.28 mm2/(kg·s2),频带质点峰值振动速度分别降低65%和37%,能量更多用于破碎和抛掷岩体,水下爆破振动主频由低频向高频带(31.25~62.50 Hz)发展。因此,在水下控制爆破设计时,需要考虑自由面数量对振动能量分布和衰减规律的影响,并利用这个特征,确定各段的控制药量,减少对周边建构物的共振危害。Abstract: Aiming at the problem that the free surface not only affected the blasting effect but also the blasting vibration effect, an analytical method of exploring the influence of free surface on the vibration attenuation law of underwater drilling blasting was proposed from the energy point of view. Taking the field monitoring data of the underwater blasting seismic wave between the river reach of the Three Gorges Dam and Gezhouba Dam as the research object, the characteristic information on time and frequency scales of the monitored signals was analyzed by wavelet transform. Similarly, the total energy of the blasting vibration signals, the energy distribution characteristics in variety of frequency band on different free surface, and the main frequency range were extracted. Combined with the method of the SPH-FEM simulation technology, the vibration velocity attenuation law of different numbers of free surfaces was verified. The results indicate that underwater drilling blasting vibration has the characteristic of low frequency, the short duration and the fast attenuation. The main frequency band of the underwater drilling blasting is focused on the frequency band of 15.625−31.250 Hz. Most of the explosion energy will be consumed as seismic energy in the underwater slotted blasting due to the restricted of a single free surface. The specific vibrational energy λE of the single free surface signal is 13.14 mm2/(kg·s2). However, with the increase of the number of free surfaces in subsequent excavation blasting, the λE of the double free surfaces and the three free surfaces decrease to 1.36 and 0.28 mm2/(kg·s2), and the reduction rates of the peak particle velocity (PPV) of the frequency band are 65% and 37%. Besides, the energy of the subsequent explosion will be used more for breaking and throwing the rock mass, and the main frequency of it will also develop from low frequency to high frequency band (31.25−62.50 Hz). Therefore, the influence of the number of free surfaces on the vibration energy distribution and attenuation law should be considered in the design of underwater controlled blasting. Using this regularity and characteristic, it is possible to more accurately determine the controlled explosive charge of each segment and reduce the resonance hazard to surrounding structures.
-
表 1 爆破振动信号的能量分布
Table 1. Energy distribution of blasting vibration signals
频带 频率/Hz 频带能量/(mm2·s−2) 能量占比/% 1-1 1-2 2-1 2-2 1-1 1-2 2-1 2-2 d8 0~7.8125 2.6287 0.1087 0.8633 0.3083 0.10 0.04 0.51 0.919 d7 7.8125~15.625 24.4471 0.1631 2.5392 0.4864 0.93 0.06 1.50 1.450 d6 15.625~31.25 2147.6642 194.0952 117.3110 17.4006 81.70 71.40 69.30 51.890 d5 31.25~62.5 312.8177 64.6168 37.8002 11.1425 11.90 23.77 22.33 33.228 d4 62.5~125 105.4117 8.9708 8.1254 4.1473 4.01 3.30 4.80 12.368 d3 125~250 26.2872 3.2621 2.6069 0.0377 1.00 1.20 1.54 0.112 d2 250~500 7.0975 0.5709 0.0288 0.0103 0.27 0.21 0.017 0.031 d1 500~1000 2.3658 0.0054 0.0005 0.0003 0.09 0.02 0.003 0.001 总和 2628.72 271.79 169.28 33.53 表 2 岩石的HJC模型主要参数
Table 2. HJC model parameters of rock
密度
ρ0/(g·cm−3)剪切模量
G/GPa黏性常数
A压力强化系数
B应变率系数
C硬化指数
N静态单轴抗压
强度fc/MPa最大拉应力
T/MPa归一化最强值
Sf,max2.6 7.42 0.3 2.01 0.009 7 0.7 113 11.3 11 损伤常数
D1损伤常数
D2压力常数
K1压力常数
K2压力常数
K3压实应变
μlock压碎体压力
pcrush/MPa压实应力
plock/MPa破碎体积应变
μcrush0.4 1 0.085 −0.171 0.208 0.1 38 800 0.004 -
[1] 李洪涛, 杨兴国, 舒大强, 等. 不同爆源形式的爆破地震能量分布特征 [J]. 四川大学学报(工程科学版), 2010, 42(1): 30–34. DOI: 10.15961/j.jsuese.2010.01.025.LI H T, YANG X G, SHU D Q, et al. Study on energy distribution characteristics of seismic waves induced by different forms of blasting resource [J]. Journal of Sichuan University (Engineering Science Edition), 2010, 42(1): 30–34. DOI: 10.15961/j.jsuese.2010.01.025. [2] 吴从师, 徐荣文, 张庆彬. 自由面对爆破振动信号能量分布特征的影响 [J]. 爆炸与冲击, 2017, 37(6): 907–914. DOI: 10.11883/1001-1455(2017)06-0907-08.WU C S, XU R W, ZHANG Q B. Influence of free surface on energy distribution characteristics of blasting vibration [J]. Explosion and Shock Waves, 2017, 37(6): 907–914. DOI: 10.11883/1001-1455(2017)06-0907-08. [3] 汪万红, 冷振东, 卢文波, 等. 临空面数量对爆破振动特征的影响研究 [J]. 矿冶工程, 2018, 38(6): 17–22. DOI: 10.3969/j.issn.0253-6099.2018.06.004.WANG W H, LENG Z D, LU W B, et al. Effect of free face numbers on blasting vibration in rock blasting [J]. Mining and Metallurgical Engineering, 2018, 38(6): 17–22. DOI: 10.3969/j.issn.0253-6099.2018.06.004. [4] 杨建华, 卢文波, 严鹏, 等. 全断面开挖爆破产生的自由面对振动频率的影响研究 [J]. 振动与冲击, 2016, 35(7): 193–197. DOI: 10.13465/j.cnki.jvs.2016.07.029.YANG J H, LU W B, YAN P, et al. Influences of blast-created free surfaces on blasting vibration frequencies during full-face excavation [J]. Journal of Vibration and Shock, 2016, 35(7): 193–197. DOI: 10.13465/j.cnki.jvs.2016.07.029. [5] 陈星明, 肖正学, 蒲传金. 自由面对爆破地震强度影响的试验研究 [J]. 爆破, 2009, 26(4): 38–40, 56. DOI: 10.3963/j.issn.1001-487X.2009.04.010.CHEN X M, XIAO Z X, PU C J. Experimental study on influence blasting earthquake strength to free faces [J]. Blasting, 2009, 26(4): 38–40, 56. DOI: 10.3963/j.issn.1001-487X.2009.04.010. [6] 马瑞恒, 时党勇. 爆破振动信号的时频分析 [J]. 振动与冲击, 2005, 24(4): 92–95. DOI: 10.3969/j.issn.1000-3835.2005.04.026.MA R H, SHI D Y. Time-frequency analysis of blasting vibration signal [J]. Journal of Vibration and Shock, 2005, 24(4): 92–95. DOI: 10.3969/j.issn.1000-3835.2005.04.026. [7] 孙苗, 吴立, 周玉纯, 等. 水下钻孔爆破地震波信号的最优降噪光滑模型 [J]. 华南理工大学学报(自然科学版), 2019, 47(8): 31–37. DOI: 10.12141/j.issn.1000-565X.180601.SUN M, WU L, ZHOU Y C, et al. Optimal denoising smooth model of underwater drilling blasting seismic wave signal [J]. Journal of South China University of Technology (Natural Science Edition), 2019, 47(8): 31–37. DOI: 10.12141/j.issn.1000-565X.180601. [8] 孙苗, 吴立, 袁青, 等. 基于CEEMDAN的爆破地震波信号时频分析 [J]. 华南理工大学学报(自然科学版), 2020, 48(3): 76–82. DOI: 10.12141/j.issn.1000-565X.190179.SUN M, WU L, YANG Q, et al. Time-Frequency analysis of blasting seismic signal based on CEEMDAN [J]. Journal of South China University of Technology (Natural Science Edition), 2020, 48(3): 76–82. DOI: 10.12141/j.issn.1000-565X.190179. [9] 李夕兵, 凌同华. 单段与多段微差爆破地震的反应谱特征分析 [J]. 岩石力学与工程学报, 2005, 24(14): 2409–2413. DOI: 10.3321/j.issn:1000-6915.2005.14.002.LI X B, LING T H. Response spectrum analysis of ground vibration induced by single deck and multi-deck blasting [J]. Chinese Journal of Rock Mechanics and Engineering, 2005, 24(14): 2409–2413. DOI: 10.3321/j.issn:1000-6915.2005.14.002. [10] 张声辉, 刘连生, 钟清亮, 等. 露天边坡爆破地震波能量分布特征研究 [J]. 振动与冲击, 2019, 38(7): 224–232. DOI: 10.13465/j.cnki.jvs.2019.07.032.ZHANG S H, LIU L S, ZHONG Q L, et al. Energy distribution characteristics of blast seismic wave on open pit slope [J]. Journal of Vibration and Shock, 2019, 38(7): 224–232. DOI: 10.13465/j.cnki.jvs.2019.07.032. [11] 陈江海, 顾文彬, 王振雄, 等. 洋山港水下多孔爆破陆地和水底震动实地测试与分析 [J]. 振动与冲击, 2016, 35(24): 207–212,220. DOI: 10.13465/j.cnki.jvs.2016.24.033.CHEN J H, GU W B, WANG Z X, et al. Field measurement and signal analysis of land and water bottom vibrations induced by underwater multi-hole blasting at Yangshan Port [J]. Journal of Vibration and Shock, 2016, 35(24): 207–212,220. DOI: 10.13465/j.cnki.jvs.2016.24.033. [12] 中国生, 房营光, 徐国元. 基于小波变换的建(构)筑物爆破振动效应评估研究 [J]. 振动与冲击, 2008, 27(8): 121–124,129. DOI: 10.13465/j.cnki.jvs.2008.08.038.ZHONG G S, FANG Y G, XU G Y. Study on blasting vibration effect assessment of structure based on wavelet transform [J]. Journal of Vibration and Shock, 2008, 27(8): 121–124,129. DOI: 10.13465/j.cnki.jvs.2008.08.038. [13] 凌同华, 李夕兵, 王桂尧, 等. 爆心距对爆破振动信号频带能量分布的影响 [J]. 重庆建筑大学学报, 2007, 29(2): 53–55. DOI: 10.11835/j.issn.1674-4764.2007.02.013.LING T H, LI X B, WANG G Y, et al. Influence of distance from blasting center on frequency bands energy distribution of blasting vibration signals [J]. Journal of Chongqing Jianzhu University, 2007, 29(2): 53–55. DOI: 10.11835/j.issn.1674-4764.2007.02.013. [14] 李夕兵, 凌同华, 张义平. 爆破震动信号分析理论与技术 [M]. 北京: 科学出版社, 2009: 92−94. [15] 胡英国, 卢文波, 陈明, 等. SPH-FEM耦合爆破损伤分析方法的实现与验证 [J]. 岩石力学与工程学报, 2015, 34(S1): 2740–2748. DOI: 10.13722/j.cnki.jrme.2014.0104.HU Y G, LU W B, CHEN M, et al. Implementation and verification of SPH-FEM coupling blasting damage analytical method [J]. Chinese Journal of Rock Mechanics and Engineering, 2015, 34(S1): 2740–2748. DOI: 10.13722/j.cnki.jrme.2014.0104. [16] 冷振东, 卢文波, 胡浩然, 等. 爆生自由面对边坡微差爆破诱发振动峰值的影响 [J]. 岩石力学与工程学报, 2016, 35(9): 1815–1822. DOI: 10.13722/j.cnki.jrme.2015.1499.LENG Z D, LU W B, HU H R, et al. Studies on influence of blast-created free face on ground vibration in slope blasts with millisecond-delays [J]. Chinese Journal of Rock Mechanics and Engineering, 2016, 35(9): 1815–1822. DOI: 10.13722/j.cnki.jrme.2015.1499. [17] 彭亚雄. 水下钻孔爆破地震波与水击波协同作用下桥墩动力响应特征研究 [D]. 武汉: 中国地质大学(武汉), 2018: 83−84. [18] 李建阳, 李永池, 高光发. 混凝土水下径向不耦合爆破特性研究 [J]. 工程爆破, 2010, 16(1): 1–5. DOI: 10.3969/j.issn.1006-7051.2010.01.001.LI J Y, LI Y C, GAO G F. Study on blasting characteristics of underwater concrete with radial decoupling charge [J]. Engineering Blasting, 2010, 16(1): 1–5. DOI: 10.3969/j.issn.1006-7051.2010.01.001. [19] 鞠杨, 环小丰, 宋振铎, 等. 损伤围岩中爆炸应力波动的数值模拟 [J]. 爆炸与冲击, 2007, 27(2): 136–142. DOI: 10.11883/1001-1455(2007)02-0136-07.JU Y, HUAN X F, SONG Z D, et al. Numerical analyses of blast wave stress propagation and damage evolution in rock masses [J]. Explosion and Shock Waves, 2007, 27(2): 136–142. DOI: 10.11883/1001-1455(2007)02-0136-07.