Research progress and future prospect of blasting theory and technology for deep rock masses: A review primarily based on Chinese perspectives

Abstract

Shallow mineral resources are gradually depleting worldwide, therefore, deep mining is becoming increasingly prevalent within the mining industry. Drilling and blasting are the predominant excavation methods used in deep environments. However, challenges such as inefficient borehole utilization and significant over- or under-excavation are frequently encountered. Scientific investigations on deep rock mass blasting are crucial for the effective development and utilization of deep resources, underpinning safe and efficient deep mine operations. This paper identifies the challenges faced in deep rock mass blasting and presents a review of the current research, primarily from the perspective of Chinese institutions and their experiences, integrating theoretical and technical perspectives through a bibliometric analysis. First, key developmental trends and prominent research teams were identified in the context of this review. Subsequently, three principal areas of theoretical research are analyzed and summarized: blasting stress field evolution, crack propagation behavior, and vibrational response characteristics under in-situ stress conditions. The application and optimization of cut and perimeter blasting techniques for deep rock masses were also examined. Finally, drawing upon existing research, this study explores three key future directions: prediction of blasting effects, utilization of unloading stress waves for cooperative rock fragmentation, and optimization of production blasting in deep metal mines. This review aims to provide a systematic framework for future research in the field of deep rock mass blasting.

1. Introduction

The increasing depletion of global mineral resources coupled with rising demand is driving the mining industry to greater depths [1]. Deep mines worldwide commonly exceed 1000 m, with some metal mines reaching depths > 4000 m. For example, the Mponeng Gold Mine in South Africa extends beyond 3900 m, ranking it among the world’s deepest mines [2]. This trend of increasing mining depth is evident in major mining nations such as South Africa, Australia, Canada, and China. As a country with significant deep mining activities, China provides a valuable context for reviewing the associated challenges and technological advancements. Driven by the resource demand, this trend presents significant technical and safety challenges. The high temperature, pressure, and rock stability issues encountered in deep environments considerably increase the complexity of deep rock mass blasting [3].

Drilling and blasting are among the most widely adopted and technologically mature excavation methods used in deep mining, particularly for large, complex orebodies. Offering advantages in terms of cost and operational flexibility, drilling and blasting can adapt to diverse geological conditions and are extensively utilized in deep mining and tunnel development. However, increasing the depth introduces new challenges, such as high in-situ stress, which significantly affects energy transfer and rock fragmentation [4–6]. High in-situ stress alters the mechanical properties of the rock mass, making it more difficult to fracture and resulting in suboptimal fragmentation and poor borehole utilization [7]. Consequently, over- and under-excavation have become prevalent, complicating subsequent construction. Critically, this practice increases costs, generates significant blast-induced vibrations, and can trigger geological hazards, such as rock bursts, posing significant safety risks. Therefore, the geological complexities of deep environments necessitate optimized blasting designs and techniques to ensure effectiveness and safety.