地铁隧道精确延时爆破振动传播规律与控制试验研究
发布时间：2018-08-01 14:09
【摘要】：城市地铁钻爆法修建过程中,由于岩体开挖的位置距地面较近,对爆破振动控制严格。电子雷管的使用使精确微差延期成为现实。越来越多的地铁爆破施工采用电子雷管起爆技术,电子雷管爆破在改善岩石破碎效果、减小爆破振动强度方面有着无可比拟的优势。目前爆破工程界还未建立微差延期间隔与岩石破碎和振动控制效果间的理论关系,现场施工更多依靠经验和多次试验确定电子雷管延期时间,对地铁隧道精确延时的爆破振动控制进行深入研究已迫在眉睫。本文依托国家自然科学基金“围压环境爆破荷载作用下地下结构累积损伤动力响应特性研究(51374212)”,以北京地铁、深圳地铁等地铁隧道钻爆法施工为工程背景,对地铁隧道精确延时爆破振动控制进行了深入研究分析。采用理论计算、现场试验和数值计算等方法,从改善岩石破碎效果、减小爆破振动强度两方面探讨了精确延时的合理孔间延期和段间延期时间,分析了地铁隧道爆破对邻近隧道结构和地面建筑的影响,研究内容主要有以下几个方面:(1)基于已有的HHT方法在爆破信号分析方面的不足,提出了相应的改进措施。通过计算分解时间、不同迭代次数的过度极值和对不同分解次数得到的各IMF分量与原始分量的相关系数的计算结果,得到了CEEMD的合理的集总平均次数为200—300次。提出了数据内部端点极值点的确定、数据外部非平稳信号向平稳信号过渡阶段的数据扩展和过渡段向平稳信号延拓的数据延拓“过渡段—平稳段”的信号端点处理方法。将提出的端点处理方法嵌入CEEMD中,对仿真信号和实际信号的分解结果表明,该方法保留了原始信号在端点处的延伸趋势,减小了迭代次数和由高频间歇噪声等造成的信号突变形成的包络线“欠冲”和“过冲”,剔除延拓的数据能保证原始数据不受到端点波动的影响。(2)将解相关算法嵌入CEEMD分解中,采用本文提出的端点处理方法、解相关算法和CEEMD方法的信号联合处理方式,能有效的抑制信号模态混叠现象,避免虚假分量带来的能量损失。仿真信号的计算结果表明,该方法分解精度比EMD和CEEMD高,处理信号内模态混叠和虚假分量的效果较好,通过多次迭代计算可以得到较好的分解效果;同时基本保证了实际信号中每个IMF内非主频率信号的能量比例较低。(3)现场试验结果表明:隧道埋深较大时,由于高频波被大量吸收,信号主频较低,主频随距离的变化改变量较小,很难通过设置电子雷管的微差间隔提高爆破主频。此时需通过降低单孔及最大单段药量来控制爆破振动强度。采用三排掏槽孔进行爆破施工,从减振效果和提高掘进速率两方面均较双排掏槽有着明显的提升。孔间微差的设置要综合考虑降低爆破振动和提高爆破效果两方面因素。选择掏槽孔延期间隔为2ms,其它类型炮孔微差间隔为4ms,在保证爆破振速不超标的前提下,加强了围岩的破碎效果,减少了机械二次破碎岩石几率。邻近隧道迎爆侧振动强度远大于背爆侧,由于上台阶开挖出的临空面效应,使下台阶整体上爆破振动速度小于上台阶爆破。隧道迎爆侧在掌子面前后1d范围内振动强度较大,隧道内爆破主频分布在30—90hz之间,不会引起邻近隧道结构的共振,结构的损伤主要受振动速度的影响。提出了“速度—频率—能量”的安全判定标准,将信号中小于20hz的能量比例加入原有安全允许标准中,新提出的标准较以往的安全标准更全面。(4)从爆破振动三要素和能量的角度分析了电子雷管和非电子雷管在爆破振动控制和改善爆破效果的差异,在隧道截面面积、炮孔布置形式和炮孔数量整体上基本相同的情况下,电子雷管可以实现逐孔起爆,爆破振动强度较普通毫秒延期雷管有大幅度的下降,并能增加单次爆破进尺。采用线性叠加法构造不同延期时间下的爆破叠加应力波形,当延期时间在波形主振半周期范围内,叠加峰值振速明显减小,振动主频有不同程度的提升,0—20hz内的能量比例同时会有较大程度的降低。半周期叠加振速可能并非合成波的最小振速峰值,当t/2tt时,叠加振速出现增大的情况;微差爆破的总能量基本小于炮孔同时起爆时的总能量,波形半周期及较近时间范围内总能量有最小值,并出现叠加能量大于单孔能量的情况,证明了实际应用中采用半周期起爆进行爆破振动控制较难。(5)提出了改善岩石破碎效果的合理孔间和段间爆破延期计算公式。计算方法综合考虑了单孔装药量、炮孔与掌子面夹角、装药长度、不耦合系数、岩体性质、抛掷岩体的质量和体积、炸药属性、进尺深度等诸多因素。使用电子雷管进行精确延期爆破控制确定的延期时间必须不小于形成新的自由面需要的时间。根据计算结果,最终确定掏槽孔的孔间延期设置为3—4ms;内圈孔、二圈孔等辅助孔延期设置为3—5ms。进尺为1.0m时,设置各段别延期间隔为30ms;进尺1.5m时,掏槽段采用45ms延期,非掏槽段采用40ms延期间隔;进尺在2m时,掏槽段采用50ms大延期间隔,非掏槽段采用45ms延期间隔。(6)邻近隧道爆破数值模拟结果表明:爆破参数相同时,圆形隧道的结构形式受爆破振动时的响应较小,马蹄形隧道的抗振性相对较差。上台阶爆破时圆形隧道和马蹄形隧道在迎爆侧拱肩至帮部范围受到的振动强度最大。随着隧道间距的增大,迎爆侧质点振速出现“断层”式衰减。间距为2.0d时,迎爆侧各部位受到的爆破振动强度趋于一致。段药量相同时,掏槽孔为6炮孔起爆有效的分散爆破能量,并减小了爆破进尺,引起的爆破振动强度小于4炮孔爆破。隧道间距小于1.0d时,单孔药量为1.8kg和2.6kg的爆破施工对结构影响较大,容易造成隧道破坏。三个方向的最大振动速度并非严格出现在与掌子面平行的垂直平面上,振动速度在隧道纵向前后5m范围内呈振荡变化。(7)提出了考虑相邻炮孔间距的隧道迎爆侧孔间延期的计算公式。合理的延期时间主要与相邻炮孔到监测点的距离差、单孔药量、爆心距和岩体性质有关。在一定距离内,相邻炮孔到监测点的距离差对延期时间的影响最大、爆心距次之、单孔药量对延期时间的影响最小。迎爆侧不同位置,得到的孔间最佳延期时间存在差异。计算结果同时要符合形成新的自由面的最短延期时间的要求,即不小于3ms。选取圆形隧道相同爆破参数在不同延期时间下的振动波形分析。结果表明合理的延期时间下,信号相邻应力波的波峰和波谷相遇的比例较大,减小了峰值振速,并能提高振动主频。随着延期时间的增加,爆炸应力波施加于同一位置的荷载逐渐分散,减少了相邻波形峰峰叠加概率,峰值能量得到有效控制。数值模拟的结果和理论计算结果基本一致,提出的计算公式切实可行。隧道不同的部位,应力波的减振效果不同。迎爆侧拱肩和帮部在微差爆破时的振动速度远小于炮孔同时起爆的振速。延期时间较小时,迎爆侧甚至出现小延期爆破振动强度大于炮孔同时起爆的情形。综合考虑炮孔间距的差异对叠加振速的影响,形成新的自由面的最小延期时间和实际监测到的不同延期下隧道迎爆侧最大振速的变化情况,在相邻隧道不同间距下,给出不同隧道间距下掏槽孔为4炮孔,单孔药量2.6kg时孔间延期为5—6ms;单孔药量1.2kg时,孔间延期为3—5ms;掏槽孔为6炮孔,单孔药量1.8kg时,孔间延期为4—6ms。(8)对不同延期时间下的掏槽孔爆破实测波形的反应谱和CEEMD分析可知,输入信号的振动强度是影响反应谱面积最主要因素,归一化反应谱面积和能量集中程度呈正比,即能量越集中,归一化谱面积越大,能量分布的越分散,归一化谱面积越小。速度反应效应的变化趋势和速度谱面积相同,二者对于建筑安全的评估具有等效性。微差间隔时间的选择应综合信号的振动强度、能量在各频带的分布、反应谱面积和速度反应效应,从能量的角度分析爆破振动特征与建筑结构对外部激励响应的综合特性。
[Abstract]:During the construction of subway drilling and blasting in urban subway, the blasting vibration control is strict because the position of rock mass excavation is closer to the ground. The use of electronic detonator makes the exact differential delay a reality. More and more subway blasting uses electronic detonator initiation technology. The electronic detonator blasting can improve the rock breaking effect and reduce the blasting vibration intensity. There is an unparalleled advantage in the field. At present, the theoretical relationship between the delay interval of the blasting and the effect of rock breaking and vibration control has not been established. The field construction relies more on experience and many experiments to determine the delay time of the electronic detonator. It is imminent to study the precise delay of the blasting vibration control of the subway tunnel. Based on the National Natural Science Foundation "study on dynamic response characteristics of cumulative damage of underground structures under ambient pressure environment blasting load (51374212)", the construction of drilling and blasting method for subway tunnels, such as Beijing subway and Shenzhen subway, is taken as the engineering background. The precise delay blasting vibration control of subway tunnel is deeply studied and analyzed. In the field test and numerical calculation, the reasonable delay time delay and intersection delay time are discussed from two aspects of improving the rock breaking effect and reducing the blasting vibration intensity. The influence of the subway tunnel blasting on the adjacent tunnel structure and the ground building is analyzed. The main contents are as follows: (1) based on the existing HHT Methods in the analysis of blasting signal, the corresponding improvement measures are put forward. By calculating the calculation results of the decomposition time, the excessive extremum of different iterations and the correlation coefficients of the IMF components and the original components obtained from different decomposition times, the reasonable total average number of CEEMD is obtained from 200 to 300 times. The determination of the extreme point of the internal endpoint, the data extension of the non stationary signal to the stationary signal in the external data and the extension of the transition segment to the stationary signal extension to the signal endpoint processing of the transition segment stationary phase. The proposed endpoint processing method is embedded in the CEEMD, and the decomposition results of the simulation signal and the actual signal show that the results of the simulation signal and the actual signal are shown. This method preserves the extension trend of the original signal at the end point, reduces the number of iterations and the envelope "undershoot" and "overshoot" from the mutation of the signal caused by the high frequency intermittent noise. The elimination of the extension data can ensure that the original data is not affected by the fluctuation of the endpoint. (2) the solution correlation algorithm is embedded in the CEEMD decomposition. The end point processing method proposed in this paper, the correlation algorithm and the signal joint processing method of CEEMD method, can effectively suppress the signal modal aliasing and avoid the energy loss caused by the false components. The simulation results show that the method has higher resolution than EMD and CEEMD, and the effect of processing the modal aliasing and false components in the signal is better than that of the simulation signal. Well, a good decomposition effect can be obtained through multiple iterations. At the same time, the energy ratio of each IMF signal in the actual signal is low. (3) field test results show that the main frequency of the signal is lower and the main frequency changes with the distance with a large amount of high frequency wave, and it is difficult to pass the tunnel when the depth of the tunnel is large. By setting the difference interval of the electronic detonator to increase the main frequency of blasting, it is necessary to control the blasting vibration intensity by reducing the single hole and the maximum single stage dosage. The three row of cutting holes are used to carry out the blasting construction. From the two aspects of the vibration damping effect and the increase of the driving speed, the blasting is obviously lifted. The setting of the gap between the holes should be comprehensively considered and reduced. The blasting vibration and the improvement of the blasting effect are two factors. The delay interval of the cutting hole is 2ms, the other type of the hole gap is 4ms. Under the premise that the blasting vibration speed is not exceeding the standard, the crushing effect of the surrounding rock is strengthened and the two broken rock probability is reduced. The vibration intensity of the adjacent tunnel is far greater than the back side, because of the platform. The blasting vibration speed of the lower step is less than that of the upper step blasting. The vibration intensity of the tunnel is larger in the 1D range of the front and rear side of the tunnel. The main frequency of the blasting in the tunnel is between 30 and 90hz, which will not cause the resonance of the adjacent tunnel structure, and the damage of the structure is mainly influenced by the vibration velocity. " The safety criterion of speed frequency energy is added to the original safety allowable standard. The new standard is more comprehensive than the previous safety standards. (4) the blasting vibration control and improvement effect of electronic detonator and non electric detonator are analyzed from the angle of three elements and energy of blasting vibration. In the case of the section area of the tunnel, the layout of the gun hole and the number of the holes on the whole, the electronic detonator can be detonated by hole by hole. The blasting vibration intensity is reduced greatly than that of the ordinary millisecond delay detonator and can increase the length of the single blasting. The blasting superposition under different delay time is constructed by the linear superposition method. The stress waveform, when the delay time is in the half cycle of the waveform, the superposition peak vibration speed is obviously reduced, the main frequency of the vibration is promoted in different degrees. The ratio of the energy in the 0 - 20Hz will be greatly reduced. The superposition velocity of the half cycle may not be the minimum peak of the vibration velocity of the synthetic wave. When t/2tt, the superposition of the velocity of vibration increases. The total energy of the millisecond blasting is less than the total energy when the hole is detonated at the same time. The total energy in the half cycle of the waveform and the total energy in the near time range is minimum, and the superimposed energy is greater than the single hole energy. It is proved that it is difficult to control the blasting vibration in the practical application. (5) the effect of rock breaking is improved. The calculation method of the delay between the hole and the interval is considered. The calculation method takes into account the amount of single hole charge, the angle of the hole and the face, the length of the charge, the uncoupling coefficient, the rock mass, the mass and volume of rock mass, the property of the explosive, the depth of the scale and so on. The delay time determined by the precise delay blasting control by using electronic mine pipe must be used. It is not less than the time required to form a new free surface. According to the calculation results, it is finally determined that the delay of the hole in the hole is set to 3 - 4ms; when the auxiliary holes of the inner ring hole and two ring hole are set to 3 - 5ms. to 1.0m, the delay interval of each paragraph is 30ms; when the footage is 1.5m, the slot section is delayed by 45ms and the non cutting section adopts the 40ms extension period. At 2m, the cutting section adopts 50ms large delay interval, and the non cutting section adopts 45ms delay interval. (6) the numerical simulation results of the adjacent tunnel blasting show that the structure of the circular tunnel is less responsive to blasting vibration when the blasting parameters are the same, and the vibration resistance of the horseshoe tunnel is relatively poor. With the increase of the distance between the tunnel and the tunnel, the vibration intensity of the mass point of the attack side appears "fault" attenuation. When the distance is 2.0D, the blasting vibration intensity of each part of the attack side is consistent. At the same time, the cutting hole is the effective dispersed blasting energy of the 6 hole. The blasting vibration strength is reduced, and the blasting vibration intensity is less than 4 hole blasting. When the distance of the tunnel is less than 1.0d, the blasting construction with the single hole dosage of 1.8kg and 2.6kg has great influence on the structure and easily causes the tunnel destruction. The maximum vibration velocity of the three directions is not strictly in the vertical plane parallel to the face of the palm, and the vibration velocity is in the tunnel. The 5m range is oscillatory in the range of the longitudinal direction. (7) a formula for the delay between the adjacent holes in the tunnel is proposed. The reasonable delay time is mainly related to the distance difference between the adjacent cannon holes and the monitoring points, the single hole dosage, the detonating distance and the rock mass property. The effect of the interval is the most, the single hole dosage has the smallest effect on the delay time. The optimal delay time between the holes is different. The calculation results should meet the requirement of the shortest delay time for the formation of the new free surface, that is, not less than 3ms., the same blasting parameters in the circular tunnel are selected at different delay time. The results show that the proportion of the peak and the trough of the adjacent stress wave is larger in the reasonable delay time. The peak vibration speed is reduced and the main frequency of the vibration can be improved. With the increase of the delay time, the load of the explosion stress wave is gradually dispersed in the same position, reducing the superposition probability and peak of the adjacent wave peak and peak. The results of numerical simulation are effectively controlled. The results of the numerical simulation are basically in agreement with the theoretical calculation results. The proposed formula is feasible. The effect of the stress wave is different in different parts of the tunnel. The vibration velocity of the arch shoulder and the help part in the blasting side is much less than that of the hole at the same time. The vibration intensity of the small delay blasting is greater than that of the hole at the same time. Considering the influence of the difference of the hole spacing on the superimposed vibration speed, the minimum delay time of the new free surface and the change of the maximum vibration speed of the tunnel under the different delay are observed. Different tunnels are given for different tunnels under the different distance between the adjacent tunnels. The gap between the holes is 4 holes, and the single hole charge 2.6kg is delayed to 5 - 6ms when the single hole dose is 2.6kg. When the single hole dose is 1.2kg, the hole is delayed to 3 - 5ms; the hole is 6 hole and the single hole dosage is 1.8kg, the interval between the holes is 4 - 6ms. (8). The vibration intensity of the measured waveform of the cut hole blasting under different delay time can be seen, the vibration intensity of the input signal is known. It is the most important factor affecting the area of the response spectrum. The normalized response spectrum area is proportional to the concentration of the energy concentration, that is, the more centralized the energy is, the greater the normalized spectral area, the more dispersed the energy distribution, the smaller the normalized spectral area. The change trend of the velocity response effect is the same as the velocity spectrum area, and the two are equivalent to the assessment of the building safety. The choice of interval time should be the vibration intensity of the integrated signal, the distribution of energy in each frequency band, the response spectrum area and the response effect. The comprehensive characteristics of the blasting vibration characteristics and the external excitation response of the building structure are analyzed from the point of view of the energy.
【学位授予单位】：中国矿业大学(北京)
【学位级别】：博士
【学位授予年份】：2016
【分类号】：U455.6
[Abstract]:During the construction of subway drilling and blasting in urban subway, the blasting vibration control is strict because the position of rock mass excavation is closer to the ground. The use of electronic detonator makes the exact differential delay a reality. More and more subway blasting uses electronic detonator initiation technology. The electronic detonator blasting can improve the rock breaking effect and reduce the blasting vibration intensity. There is an unparalleled advantage in the field. At present, the theoretical relationship between the delay interval of the blasting and the effect of rock breaking and vibration control has not been established. The field construction relies more on experience and many experiments to determine the delay time of the electronic detonator. It is imminent to study the precise delay of the blasting vibration control of the subway tunnel. Based on the National Natural Science Foundation "study on dynamic response characteristics of cumulative damage of underground structures under ambient pressure environment blasting load (51374212)", the construction of drilling and blasting method for subway tunnels, such as Beijing subway and Shenzhen subway, is taken as the engineering background. The precise delay blasting vibration control of subway tunnel is deeply studied and analyzed. In the field test and numerical calculation, the reasonable delay time delay and intersection delay time are discussed from two aspects of improving the rock breaking effect and reducing the blasting vibration intensity. The influence of the subway tunnel blasting on the adjacent tunnel structure and the ground building is analyzed. The main contents are as follows: (1) based on the existing HHT Methods in the analysis of blasting signal, the corresponding improvement measures are put forward. By calculating the calculation results of the decomposition time, the excessive extremum of different iterations and the correlation coefficients of the IMF components and the original components obtained from different decomposition times, the reasonable total average number of CEEMD is obtained from 200 to 300 times. The determination of the extreme point of the internal endpoint, the data extension of the non stationary signal to the stationary signal in the external data and the extension of the transition segment to the stationary signal extension to the signal endpoint processing of the transition segment stationary phase. The proposed endpoint processing method is embedded in the CEEMD, and the decomposition results of the simulation signal and the actual signal show that the results of the simulation signal and the actual signal are shown. This method preserves the extension trend of the original signal at the end point, reduces the number of iterations and the envelope "undershoot" and "overshoot" from the mutation of the signal caused by the high frequency intermittent noise. The elimination of the extension data can ensure that the original data is not affected by the fluctuation of the endpoint. (2) the solution correlation algorithm is embedded in the CEEMD decomposition. The end point processing method proposed in this paper, the correlation algorithm and the signal joint processing method of CEEMD method, can effectively suppress the signal modal aliasing and avoid the energy loss caused by the false components. The simulation results show that the method has higher resolution than EMD and CEEMD, and the effect of processing the modal aliasing and false components in the signal is better than that of the simulation signal. Well, a good decomposition effect can be obtained through multiple iterations. At the same time, the energy ratio of each IMF signal in the actual signal is low. (3) field test results show that the main frequency of the signal is lower and the main frequency changes with the distance with a large amount of high frequency wave, and it is difficult to pass the tunnel when the depth of the tunnel is large. By setting the difference interval of the electronic detonator to increase the main frequency of blasting, it is necessary to control the blasting vibration intensity by reducing the single hole and the maximum single stage dosage. The three row of cutting holes are used to carry out the blasting construction. From the two aspects of the vibration damping effect and the increase of the driving speed, the blasting is obviously lifted. The setting of the gap between the holes should be comprehensively considered and reduced. The blasting vibration and the improvement of the blasting effect are two factors. The delay interval of the cutting hole is 2ms, the other type of the hole gap is 4ms. Under the premise that the blasting vibration speed is not exceeding the standard, the crushing effect of the surrounding rock is strengthened and the two broken rock probability is reduced. The vibration intensity of the adjacent tunnel is far greater than the back side, because of the platform. The blasting vibration speed of the lower step is less than that of the upper step blasting. The vibration intensity of the tunnel is larger in the 1D range of the front and rear side of the tunnel. The main frequency of the blasting in the tunnel is between 30 and 90hz, which will not cause the resonance of the adjacent tunnel structure, and the damage of the structure is mainly influenced by the vibration velocity. " The safety criterion of speed frequency energy is added to the original safety allowable standard. The new standard is more comprehensive than the previous safety standards. (4) the blasting vibration control and improvement effect of electronic detonator and non electric detonator are analyzed from the angle of three elements and energy of blasting vibration. In the case of the section area of the tunnel, the layout of the gun hole and the number of the holes on the whole, the electronic detonator can be detonated by hole by hole. The blasting vibration intensity is reduced greatly than that of the ordinary millisecond delay detonator and can increase the length of the single blasting. The blasting superposition under different delay time is constructed by the linear superposition method. The stress waveform, when the delay time is in the half cycle of the waveform, the superposition peak vibration speed is obviously reduced, the main frequency of the vibration is promoted in different degrees. The ratio of the energy in the 0 - 20Hz will be greatly reduced. The superposition velocity of the half cycle may not be the minimum peak of the vibration velocity of the synthetic wave. When t/2tt, the superposition of the velocity of vibration increases. The total energy of the millisecond blasting is less than the total energy when the hole is detonated at the same time. The total energy in the half cycle of the waveform and the total energy in the near time range is minimum, and the superimposed energy is greater than the single hole energy. It is proved that it is difficult to control the blasting vibration in the practical application. (5) the effect of rock breaking is improved. The calculation method of the delay between the hole and the interval is considered. The calculation method takes into account the amount of single hole charge, the angle of the hole and the face, the length of the charge, the uncoupling coefficient, the rock mass, the mass and volume of rock mass, the property of the explosive, the depth of the scale and so on. The delay time determined by the precise delay blasting control by using electronic mine pipe must be used. It is not less than the time required to form a new free surface. According to the calculation results, it is finally determined that the delay of the hole in the hole is set to 3 - 4ms; when the auxiliary holes of the inner ring hole and two ring hole are set to 3 - 5ms. to 1.0m, the delay interval of each paragraph is 30ms; when the footage is 1.5m, the slot section is delayed by 45ms and the non cutting section adopts the 40ms extension period. At 2m, the cutting section adopts 50ms large delay interval, and the non cutting section adopts 45ms delay interval. (6) the numerical simulation results of the adjacent tunnel blasting show that the structure of the circular tunnel is less responsive to blasting vibration when the blasting parameters are the same, and the vibration resistance of the horseshoe tunnel is relatively poor. With the increase of the distance between the tunnel and the tunnel, the vibration intensity of the mass point of the attack side appears "fault" attenuation. When the distance is 2.0D, the blasting vibration intensity of each part of the attack side is consistent. At the same time, the cutting hole is the effective dispersed blasting energy of the 6 hole. The blasting vibration strength is reduced, and the blasting vibration intensity is less than 4 hole blasting. When the distance of the tunnel is less than 1.0d, the blasting construction with the single hole dosage of 1.8kg and 2.6kg has great influence on the structure and easily causes the tunnel destruction. The maximum vibration velocity of the three directions is not strictly in the vertical plane parallel to the face of the palm, and the vibration velocity is in the tunnel. The 5m range is oscillatory in the range of the longitudinal direction. (7) a formula for the delay between the adjacent holes in the tunnel is proposed. The reasonable delay time is mainly related to the distance difference between the adjacent cannon holes and the monitoring points, the single hole dosage, the detonating distance and the rock mass property. The effect of the interval is the most, the single hole dosage has the smallest effect on the delay time. The optimal delay time between the holes is different. The calculation results should meet the requirement of the shortest delay time for the formation of the new free surface, that is, not less than 3ms., the same blasting parameters in the circular tunnel are selected at different delay time. The results show that the proportion of the peak and the trough of the adjacent stress wave is larger in the reasonable delay time. The peak vibration speed is reduced and the main frequency of the vibration can be improved. With the increase of the delay time, the load of the explosion stress wave is gradually dispersed in the same position, reducing the superposition probability and peak of the adjacent wave peak and peak. The results of numerical simulation are effectively controlled. The results of the numerical simulation are basically in agreement with the theoretical calculation results. The proposed formula is feasible. The effect of the stress wave is different in different parts of the tunnel. The vibration velocity of the arch shoulder and the help part in the blasting side is much less than that of the hole at the same time. The vibration intensity of the small delay blasting is greater than that of the hole at the same time. Considering the influence of the difference of the hole spacing on the superimposed vibration speed, the minimum delay time of the new free surface and the change of the maximum vibration speed of the tunnel under the different delay are observed. Different tunnels are given for different tunnels under the different distance between the adjacent tunnels. The gap between the holes is 4 holes, and the single hole charge 2.6kg is delayed to 5 - 6ms when the single hole dose is 2.6kg. When the single hole dose is 1.2kg, the hole is delayed to 3 - 5ms; the hole is 6 hole and the single hole dosage is 1.8kg, the interval between the holes is 4 - 6ms. (8). The vibration intensity of the measured waveform of the cut hole blasting under different delay time can be seen, the vibration intensity of the input signal is known. It is the most important factor affecting the area of the response spectrum. The normalized response spectrum area is proportional to the concentration of the energy concentration, that is, the more centralized the energy is, the greater the normalized spectral area, the more dispersed the energy distribution, the smaller the normalized spectral area. The change trend of the velocity response effect is the same as the velocity spectrum area, and the two are equivalent to the assessment of the building safety. The choice of interval time should be the vibration intensity of the integrated signal, the distribution of energy in each frequency band, the response spectrum area and the response effect. The comprehensive characteristics of the blasting vibration characteristics and the external excitation response of the building structure are analyzed from the point of view of the energy.
【学位授予单位】：中国矿业大学(北京)
【学位级别】：博士
【学位授予年份】：2016
【分类号】：U455.6
【参考文献】
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