基于DIC技术的爆炸应力波过异质界面应变场演化规律实验研究

杨仁树; 赵勇; 赵杰; 左进京; 葛丰源; 陈程; 丁晨曦

doi:10.11883/bzycj-2022-0097

基于DIC技术的爆炸应力波过异质界面应变场演化规律实验研究

doi: 10.11883/bzycj-2022-0097

杨仁树^{1, 2,},
赵勇^{1, 2, ,},
赵杰³,
左进京^{1, 2},
葛丰源^{1, 2},
陈程^{1, 2},
丁晨曦^{1, 4}

1.
北京科技大学土木与资源工程学院，北京 100083
2.
北京科技大学城市地下空间工程北京市重点实验室，北京 100083
3.
天津宏泰华凯科技有限公司，天津 301913
4.
江汉大学爆破工程湖北省重点实验室，湖北武汉 430056

基金项目: 国家自然科学基金（52074301）；中国博士后科学基金（2021M700386，2020TQ0032）；爆破工程湖北省重点实验室开放基金（BL2021-05）

详细信息

作者简介:
杨仁树（1963－　），男，博士，教授，博士生导师，yangrsustb@163.com

通讯作者:
赵　勇（1993－　），男，博士研究生，zhaoyong931216@126.com

中图分类号: O382
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出版历程
- 收稿日期: 2022-03-14
- 修回日期: 2022-06-26
- 网络出版日期: 2022-09-05
- 刊出日期: 2022-12-08

Experimental study on evolution of strain field of explosion stress wave passing through a heterogeneous interface based on the DIC method

YANG Renshu^{1, 2
,},
ZHAO Yong^{1, 2
, ,},
ZHAO Jie³,
ZUO Jinjing^{1, 2},
GE Fengyuan^{1, 2},
CHEN Cheng^{1, 2},
DING Chenxi^{1, 4}

1.
School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
2.
Beijing Key Laboratory of Urban Underground Space Engineering, University of Science and Technology Beijing, Beijing 100083, China
3.
Tianjin Hongtai Huakai Science and Technology Co. Ltd., Tianjin 301913, China
4.
Hubei Key Laboratory of Blasting Engineering, Jianghan University, Wuhan 430056, Hubei, China

摘要

摘要: 采用氯仿粘结聚碳酸酯（polycarbonate, PC）板和聚甲基丙烯酸甲酯（polymethylmethacrylate, PMMA）板模拟含异质界面模型；在PC介质中布置柱状炮孔并与界面呈一定角度，根据炮孔端部与界面相对位置，分别于柱状炮孔两个端部设置起爆点，起爆点远离界面端部时定义为孔口起爆，靠近界面端部时定义为孔底起爆；借助数字图像相关实验系统，研究爆炸应力波通过异质界面后PMMA介质应变场演化过程及炮孔底部区域拉、压应变变化规律。实验结果表明，异质界面改变了爆炸应力波过界面后的传播形态。孔口起爆时，异质界面受爆破荷载作用后易形成应力集中区，界面处产生开裂，横向拉伸波作用是造成异质界面开裂的主要原因。起爆方式对过界面后介质PMMA的横/纵向拉、压应变场作用贡献不同，主要体现在应变场强度、拉/压应变场位置分布2个方面。在炮孔底部区域，起爆方式对应变场时程特性的影响主要体现在作用时效长短和应变强度2个方面。孔口起爆时，横/纵向应变体现出短时效、高强度的变化特征。就应变强度而言，起爆方式对横向压应变的影响显著强于其对纵向拉应变的影响。对空间分布特性影响主要体现在衰减程度，起爆方式对纵向应变衰减程度影响较大。无论采用何种起爆方式，爆炸应变场在PC介质中衰减速度较快，进入PMMA介质后衰减速度显著降低。
- 数字图像相关法 /
- 爆炸应力波 /
- 异质界面 /
- 起爆方式 /
- 模型实验
Abstract: Chloroform was used to bond a polycarbonate (PC) plate and a polymethylmethacrylate (PMMA) plate to fabricate a model with a heterogeneous cemented interface. A cylinder blasthole was set in the PC plate with a certain angle to the interface. Base on the locations between the interface and the explosive initiation points, two kinds of initiation methods were used in the experiment. The one is the top initiation method, in which the initiation point is settled far away from the interface; and the other is the bottom initiation method, in which the initiation point is close to the interface. The digital image correlation (DIC) method was used to study the evolution of the strain field during the passage of the blast waves in the medium with the heterogeneous interface. The results show that the propagation pattern of the blast stress wave varies significantly after it passes through the interface. In the top initiation, a stress concentration zone is formed on the interface under blast loadings, and induce a crack initiate at the interface. The transverse tensile wave is the main reason for the cracking of the interface. Besides, it can be found that the initiation methods have different contributions to both the magnitude and the locations of the tensile/compressive strain in both the transverse and longitudinal directions. Moreover, in the bottom area of the borehole, the influence of the initiation method on the time-related characteristics of the strain field mainly has two aspects, namely, the duration time and the strain magnitude. And it is found that the transverse/longitudinal strain is of "short duration, high magnitude" variation characteristic for the top initiation. In terms of the strain magnitude, the influence of the initiation method on the transverse strain is much greater than it on the longitudinal strain. In addition, the initiation method can significantly influence the attenuation characteristics of the strain field, which is more obvious for the longitudinal strain field. In terms of the attenuation rate, the magnitude blast stress waves attenuated faster in the PC plate, whereas the blast stress waves attenuated slowly when it passed through the interface and propagated in the PMMA plate regardless of the initiation method.
- digital image correlation /
- blast stress wave /
- heterogeneous interface /
- initiation method /
- model experiment

HTML全文

图 1 数字图像相关方法的基本原理

Figure 1. The basic principle for the digital image correlation method

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图 2 数字图像相关实验系统

Figure 2. An experimental system based on the digital image correlation method

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图 3 试件模型

Figure 3. The specimen model

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图 4 试件受爆炸荷载作用后的断裂

Figure 4. Fracture of the specimens under explosion load

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图 5 θ=30º时的孔口起爆应变演化云图

Figure 5. Strain field evolution of the hole-top initiation at θ=30º

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图 6 θ=30º时的孔底起爆应变演化云图

Figure 6. Strain field evolution of the bottom initiation at θ=30º

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图 7 θ=60º时不同起爆方式下t=55.00 μs时的横向应变云图

Figure 7. Transverse strain fields at t=55.00 μs for different initiation modes with θ=60º

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图 8 研究区域示意图

Figure 8. Schematic diagram of the target area

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图 9 θ=30º，孔口起爆时PMMA介质拉、压应变分布可视化结果

Figure 9. Visualization results of tensile and compressive strain distribution in PMMA with the hole-top initiation at θ=30º

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图 10 θ=30º，孔底起爆时PMMA介质拉、压应变分布可视化结果

Figure 10. Visualization results of tensile and compressive strain distribution in PMMA with the hole-bottom initiation at θ=30º

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图 11 θ=60º，孔口起爆时PMMA介质拉、压应变分布可视化结果

Figure 11. Visualization results of tensile and compressive strain distribution in PMMA with the hole-top initiation at θ=60º

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图 12 θ=60º，孔底起爆时PMMA介质拉、压应变分布可视化结果

Figure 12. Visualization results of tensile and compressive strain distribution in PMMA with the hole-bottom initiation at θ=60º

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图 13 炮孔底部的测点分布

Figure 13. Distribution of measuring points at the bottom of the blasthole

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图 14 θ=30º时孔口起爆测点应变时程曲线

Figure 14. Strain time history curves at measuring points with hole-top initiation at θ=30 º

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图 15 θ=30º时孔底起爆测点应变时程曲线

Figure 15. Strain time history curves at measuring points with hole-bottom initiation at θ=30º

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图 16 应变峰值及其衰减拟合曲线

Figure 16. Strain peaks and their attenuation-fitting curves

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表 1 PC和PMMA相关材料参数^[25-26]

Table 1. Relevant material parameters of PC and PMMA^[25-26]

材料	ρ/(kg·m⁻³)	c_p/(m∙s⁻¹)	c_s/(m∙s⁻¹)	E_d/GPa	G_d/GPa	μ_d
PC	1449	2125	1090	4.5	1.7	0.32
PMMA	1240	2320	1260	6.1	1.9	0.31

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表 2 PC和PMMA介质中测点拉、压应变峰值

Table 2. Tensile and compressive strain peaks at measured points in PC and PMMA

介质	测点	x/mm	θ=30º, 孔口起爆		θ=30º, 孔底起爆		θ=60º, 孔口起爆		θ=60º, 孔底起爆
介质	测点	x/mm	ε_xx,max/10⁻⁶	ε_yy,max/10⁻⁶	ε_xx,max/10⁻⁶	ε_yy,max/10⁻⁶	ε_xx,max/10⁻⁶	ε_yy,max/10⁻⁶	ε_xx,max/10⁻⁶	ε_yy,max/10⁻⁶
PC	L1	11	13927	8445	3756	3099	11485	7400	4344	2914
	L2	9	11147	6784	2957	2243	9261	5991	3415	2230
	L3	7	9650	5473	2426	1759	7498	4934	2548	1781
	L4	5	9032	4438	1950	1462	6421	3986	1948	1522
	L5	3	8053	3513	1463	1088	5614	3143	1457	1170
PMMA	R1	5	5356	1630	1236	900	4284	1952	1256	970
	R2	15	4444	1576	1205	890	3625	1630	1042	821
	R3	25	4021	1257	1132	780	3368	1578	784	625
	R4	35	3356	1062	959	678	2946	1461	739	518
	R5	45	3275	942	960	593	2912	1211	649	490
	R6	55	2957	823	913	559	2599	1049	639	451
	R7	65	2789	812	778	511	2557	941	570	450

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表 3 应变衰减指数和应变衰减程度

Table 3. Strain attenuation index and strain attenuation degree

起爆方式	应变	衰减函数		衰减指数		(ε_L4−ε_R1)/ε_L4
起爆方式	应变	PC	PMMA	PC	PMMA	(ε_L4−ε_R1)/ε_L4
θ=30º，孔口起爆	ε_xx	ε_max=1.40x^−1.57	ε_max=56144x^−0.66	1.57	0.66	0.4070
θ=30º，孔口起爆	ε_yy	ε_max=1.01x^−2.40	ε_max=25613x^−0.76	2.40	0.76	0.6327
θ=30º，孔底起爆	ε_xx	ε_max=5.98x^−2.50	ε_max=56144x^−0.66	2.50	0.42	0.3662
θ=30º，孔底起爆	ε_yy	ε_max=1.51x^−2.89	ε_max=25613x^−0.76	2.89	0.58	0.3844
θ=60º，孔口起爆	ε_xx	ε_max=5.44x^−2.09	ε_max=27604x^−0.52	2.09	0.52	0.3328
θ=60º，孔口起爆	ε_yy	ε_max=6.94x^−2.32	ε_max=20396x^−0.65	2.32	0.65	0.5103
θ=60º，孔底起爆	ε_xx	ε_max=2.76x^−2.97	ε_max=23138x^−0.82	2.97	0.82	0.3552
θ=60º，孔底起爆	ε_yy	ε_max=4.65x^−2.50	ε_max=22053x^−0.88	2.50	0.88	0.3627

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表 4 不同测点孔口起爆应变峰值与孔底起爆应变峰值的比值

Table 4. Ratios of strain peak of top initiation to strain peak of bottom initiation at different measuring points

θ/(º)	应变	应变峰值比
		PC					PMMA
		L1	L2	L3	L4	L5	R1	R2	R3	R4	R5	R6	R7
30	ε_xx	3.7	3.8	4.0	4.6	5.5	4.3	3.7	3.6	3.5	3.4	3.2	3.6
30	ε_yy	2.7	3.0	3.1	3.0	3.2	1.8	1.8	1.6	1.6	1.6	1.5	1.6
60	ε_xx	2.6	2.7	2.9	3.3	3.9	3.4	3.5	4.3	4.0	4.5	4.1	4.5
60	ε_yy	2.5	2.7	2.8	2.6	2.7	2.0	2.0	2.5	2.8	2.5	2.3	2.1

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