With the rapid development of the national economy, and the blasting engineering is constantly increasing, and the geotechnical blasting technology is applied widely in the mine, highway, railroad, and the electric power construction, and the site preparation and pit excavation cutting excavation in the projects mentioned above need the blasting operation. And the initiation technique of delaying time is used in general rock blasting, pre-splitting blasting and smooth blasting according to the different requirements of the engineering. Especially for the deep-hole blasting under the complex environment, the neighboring people, buildings, all kinds of devices and equipments should be prevented from attaint, therefore it sets higher demands for the safety and technology of the blasting. In recent years, two kinds of blasting methods are used in the mining, civil construction, which are crater blasting and bench blasting. The effectiveness of the two blasting methods has close contact with the knowledge of the crater blasting and bench blasting. The crater blasting is different from the bench blasting because the crater blasting has the free vertical surface relative to the borehole, while there are more than two free surfaces in the bench blasting, and one is parallel to the borehole, and the other is perpendicular to the borehole. And the course of the rock fragmentation around borehole needs a big explosive force, and then a lot of explosion accidents occur frequently in mining enterprise, which cause the a large number of injuries and pecuniary loss. The reasons causing the accidents can be divided into two respects, which are human factor and objective factor. The human factors include the mistakes and disadvantages existing in the blasting technology and construction technology, the shortcoming of on-site experience of engineering and technical personnel, the loose check of the relating managing personnel and the approval in excess of authority and so on. And the objective factors include thunder and light, the quality of the blasting materials and so on.
The risk analysis of the blasting in mining is important for the predicting and controlling blasting accidents. And the risk analysis of the blasting in mining uses the quantity index as the basic data, and the score of all kinds of factors which can cause the blasting accidents in mining is added up, and then the risk ranking is carried out based on the relative risk index directly, and every factor has the same weight, therefore this method can not embody the different affecting degree of every kind of factors. It is necessary to amend the original risk evaluating method, and the proper affecting proportions of every factor on the blasting accidents, and the actual risk of the blasting in mining will be reflected.
In order to understand the effect of all risk factors on the risk probability correctly, and the grey theory is applied in the risk evaluation of the blasting in mining, and the grey theory breaks through the constraint that the tradition precious mathematics does not permit the ambiguous answer, and the association degree between the all kinds of risk factors and the accidental consequences based on the grey theory, and the risk ranking of the accident factors causing the blasting in mining is carried out according to the numeric value of the association degree, and the weight of every accident factor in the all factors in the blasting accidents in mining can be obtained. And the risk of the blasting in mining can be embodied really according to the value of the blasting risk.
The grey system theory is proposed at first by Deng, which concerning on model with uncertainty and inadequate information in studying and understanding systems based on study on conditional analysis, predicting and deciding making. The grey system defines every uncertainty variable as a grey quantity that varies within a given span. It does not depend on statistical technology cope with the grey quantity. It copes directly with the initial information, and looks for the intrinsic regularity of information. The grey predicting mathematical model applies the important part of the grey system theory. From this perspective, grey predicting can be said to confirm the evaluation completed by the application of a grey system, which is in between a white system and a black-box system.
In recent years the study on the risk evaluation based on grey theory has caused wide concern by some scientists, and very significant achievements have been acquired. A risk assessment of construction projects is put forward, and ranking of objects and determination of their optimality are determined based on TOPSIS grey and COPRAS-G method with attributes values determined at intervals. And the proposed model is offered and the main results of the research are analyzed . A proposed version of a network thinking methodology is established for identification and estimation of factors which can affect the logistic process safety in a network context based on its modified stages, and a significant element is presented based on grey systems theory’s method named Grey Relational Analysis quantitatively formulating a common experts’ suggestion relating with an impact mutual force of identified factors . A research of risk perceptions and understanding in OHS by workers was conducted in three sectors, such as construction, refractory, and steel industries. And Grey relational method is applied in assessing safety culture and work practices, and it is demonstrated that this method can be applied in benchmarking of organizations on these two aspects . Industrial jobs are divided into two categories i.e., low risk and high risk based on grey relational analysis method. The results on a dataset are provided, together with the comparisons in terms of classification accuracy between the proposed approach and other methods that used the same dataset. The proposed approach outperforms other alternative methods and yields at least 10% improvement in classification accuracy compared to the best results achieved among the earlier studies .An FMEA based on the fuzzy evidential reasoning (FER) approach and grey theory is put forward to solve the two problems and improve the effectiveness of the traditional FMEA, numerical example show that the proposed FMEA can well capture FMEA team members’ diversity opinions and prioritize failure modes under different types of uncertainties . A risk assessment method which combines wavelet neural network (WNN) and entropy-grey correlation is presented, and the simulation analysis is carried out by MATLAB, and results show that this method can be easily applied on the security risk assessment of the e-government information system to produce objective results . A GRAP method which concludes grey relational projection (GRP), grey prediction, and grey decision making is proposed to carry out risk assessment of ad hoc network. Compared with principal component analysis, GRAP has demonstrated better performance and more flexible characteristics. And results show that model is more effective and efficient for risk assessment than principal component analysis in ad hoc networks . The above achievements can show that the risk analysis based on grey theory has been studied by some scientists in many fields, but the application of the grey theory on the risk evaluation of the blasting in mining has not been reported in public, therefore it is truly a significant to study the blasting risk in mining based on grey theory.