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681.
立足于长期从事大型开山爆破工程的实际,客观总结了十年来山体爆破实践的成功经验,试图推荐一些新的技术和方法,以期引起同行的关注,共同拓展爆破技术的空间. 相似文献
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A knowledge-based system shell called ‘Confound’ has been developed for the production of decision support systems. It was initially used for developing a system for conceptual foundation design but has subsequently been used for retaining wall, expansive soil and ground investigation applications. It uses a hierarchical object-oriented knowledge base where each object represents a decision in the decision making process. A simple rule-based approach is used to provide advice on the suitability of each potential choice, based on project specific information that is provided by the user. Confound has the ability to work with incomplete information and uses a system of confidence levels so that the user is aware of the confidence with which each piece of advice is given. Conflicting information in areas where knowledge is poorly defined can also be handled. Confound is designed to leave the user in full control. It simply provides comments on suitability (with an indication of confidence) and leaves the final decision to the user. 相似文献
683.
In many areas of the world, the presence of shallow high velocity, highly heterogeneous layers complicate seismic imaging of deeper reflectors. Of particular economic interest are areas where potentially hydrocarbon-bearing strata are obscured by layers of basalt. Basalt layers are highly reflective and heterogeneous. Using reflection seismic, top basalt is typified by a high-amplitude, coherent reflector with poor resolution of reflectors below the basalt, and even bottom basalt. Here, we present a new approach to the imaging problem using the pattern recognition abilities of a back-propagation Artificial Neural Network (ANN). ANNs are computational systems that attempt to mimic natural biological neural networks. They have the ability to recognize patterns and develop their own generalizations about a given data set. Back-propagation neural networks are trained on data sets for which the solution is known and tested on the data that are not previously presented to the ANN in order to validate the network result. We show that Artificial Neural Networks, due to their pattern recognition capabilities, can invert the medium statistics based on the seismic character. We produce statistically defined models involving a basalt analogous layer, and calculate full wavefield finite difference synthetic seismograms. We vary basalt layer thickness and source frequency to generate a synthetic model that produces seismic that is similar to real sub-basalt seismic, i.e. high amplitude top basalt reflector and the absence of base basalt and sub-basalt events. Using synthetic shot gathers, generated in a synthetic representation of the sub-basalt case, we can invert the velocity medium standard deviation by using an ANN. By inverting the velocity medium standard deviation, we successfully identified the transition from basalt to sub-basalt on the synthetic shot gathers. We also show that ANNs are capable of identifying the basalt to sub-basalt transition in the presence of incoherent noise. This is important for any future applications of this technique to the real-world seismic data, as this data is never completely noise-free. There is always a certain level of residual (noise remaining after initial noise filtering) environmental/ambient noise present on the recorded seismics, hence, neural network training with noise-free synthetic seismic is less than optimal. 相似文献
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Design of a model blasting system to measure peak p-wave stress 总被引:4,自引:0,他引:4
Literature review information and model scale rock blasting tests have been utilized to study the effects of some blast and fragmentation parameters on peak p-wave stress. A method for modelling scaled blasting in sandstone blocks with dimensions 515×335×215 mm3 has been presented. The dynamic and static properties of the sandstone are given. The results from model blasting experiments instrumented with pressure gauges are discussed. It is also shown there exists a useful correlation between blast, fragmentation parameters and peak p-wave stress. 相似文献
688.
水不耦合炮孔装药爆破冲击波的形成和传播 总被引:1,自引:0,他引:1
探讨了炮孔和装药间以水不耦合介质爆破时,在爆轰波压力和高压、高温爆生气体压力作用下,水中爆炸冲击波的形成和传播规律,求解了冲击波的初始参数和孔壁处冲击波参数,并应用弹性波动理论,提出了正入射情况下岩石内的初始冲击压力。 相似文献
689.
简述了太子矶长江航道整治工程水下控制爆破施工情况和该地区爆破震动监测情况。振动监测表明,工程所设计的爆破方案,采用微差起爆系统对邻近的长江两岸防洪堤是安全的,为控制爆破参数和评价长江堤防的安全提供了科学依据。 相似文献
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