Longhole stoping is a productive exploitation technique for underground metalliferous deposits. The method consists of deep-hole blasting with increased explosive …
The research results demonstrated that in the single blasting-hole model, a triangular crack area caused by reflected stress waves appeared at the rock interface of rock medium I near the blast hole.
To address the problems with deep-hole presplit blasting intended to fracture and improve the ... School of Safety and Engineering, 232001 ... An inappropriate blasthole–relief hole distance will dispose the blasting energy to be distributed in the horizontal near field between the blasthole and the relief hole and promote fracturing in the ...
GB 6722-2014 English Version - GB 6722-2014 Safety regulations for blasting (English Version): GB 6722-2014, GB/T 6722-2014, GBT 6722-2014, GB6722-2014, GB 6722, GB6722, GB/T6722-2014, GB/T 6722, GB/T6722, GBT6722-2014, GBT 6722, GBT6722
Due to the hard roof caving step distance, ... analyzed the regulation effect of coal rock structure and the mechanism of load reduction and shock absorption of roof deep hole blasting in the process of working face mining. Chen et al. analyzed the influence of explosion stress wave generated by ultradeep hole blasting in coal mine roof on the ...
The suggested safety distance in deep mining. ... (about 16 times the radius of the blast hole); the designed safety distance is not enough to reduce the influenced area; therefore, the safety distance in −780 m and −1020 m are suggested to be 1.2 m and 0.8 m, respectively, that can effectively reduce influenced area of hoop tensile stress ...
Blasting must determine the scope and safety distance of blasting hazards, and set up warning and safety protection measures. ① Safe distance for blasting flying stones Blasting type Minimum safe distance for individual flying stones Shallow hole blasting to break large blocks 300m Shallow hole blasting 200m (not less than 300m under complex ...
The undercut blasting adopts the medium-deep hole fan-shaped blasting method, and the layout of the undercut engineering is shown in Fig. 15, where 1 represents the undercut roadway, 2 represents the ore exit roadway (No. 5 main roadway), and 3 represents the ore exit route. Due to the presence of two vertical ore body structural zones in the ...
The sublevel stoping mining method with delayed backfill has been widely used in various mines because it ensures stope production capacity, improves economic benefits and safety, and reduces the risk of tailings ponds [1,2,3,4].Parallel hole cut blasting is a key technology of the sublevel stoping mining method with delayed backfill [3, 5].The largest …
Based on an open-pit deep-hole blasting test. Jiang et al. conducted an analysis of the vibration characteristics caused by blasting on pipelines at various burial depths and proposed safety control standards for pipeline vibration velocity. Other scholars have studied the influence of steel large-diameter pipelines on resistance to dynamic ...
When the distance between the blasting hole and the control hole is set to 3 m, the per- ... 1 School of Urban Construction and Safety Engineering, Shanghai Institute of Technology, Shanghai 201418, China ... used deep hole blasting to carry out tests on rock roadway
School of Resources & Safety Engineering, Wuhan Institute of Technology, Hubei, Wuhan 430074, ... the guttering technology for improving the deep-hole blasting of …
It is required to determine a safety distance away from blasting work faces where the support of the secondary shotcrete can be executed to avoid damage from blasting vibration. For the case of the Jinping-II diversion tunnel, characteristics of the blast-induced vibration under high in situ stress are firstly investigated by site monitoring ...
(16) "deep-hole drilling and blasting" means drill holes made more than three metres in depth and used for blasting in an opencast mining operation; (17) "designer" means an individual, association of individuals, company or institution who designs a coal mining system, method of coal mining or machinery, plant, equipment,
Peledakan lubang dalam (deep hole blasting) merupakan Cara peledakan jenjang kuari atau tambang terbuka dengan menggunakan lubang tembak yang dalam disesuaikan dengan tinggi jenjang; ... (safety distance) antar lubang. Contoh proses detonasi terjadi pada jenis bahan peledakan antara lain: + TNT : C7H5N3O6 > 1,75 CO2 + 2,5 H2O + 1,5 N2 + 5,25 …
But so far, the mechanism of deep-hole blasting technology for controlled roof caving, in respect of the shallow depth seams beneath a room mining goaf, remains to be studied systematically. ... The 3-1-2 Coal Seam is beneath the 3-1-1 Coal Seam with a distance about 6.0 ... 3.3 MPa; n is safety factor, 1.5; and q the overlying strata's load, 1 ...
The suggested safety distance in deep mining. ... (about 16 times the radius of the blast hole); the designed safety distance is not enough to reduce the influenced area; …
Deep-hole blasting and chamber blasting technology are widely used in mining and large- ... It is observed that when the distance between millisecond blasting holes is equal to greater than 5 m ...
Applying deep hole blasting in hard composite roof caving along goaf in deep well. Jan 2013; 1588; ... In addition to the distance from the blasting center and the charge amount, the influence of ...
Pre-cracking and smooth blasting holes shall be packed as designed. 6. The pre-cracking blasthole should be detonated before the adjacent main blasting hole or buffer blasting hole, and the time difference should be no less than 75ms. The smooth blasting hole should lag behind the adjacent main blasting hole. 4. Complex environment deep hole ...
Safe distance for blasting Blasting hazards: blasting earthquakes, air shock waves, scattered debris, toxic gases. Blasting must determine the scope and safety distance of blasting hazards, and set up warning and safety protection measures. ① Safe distance for blasting flying stones Blasting type Minimum safe distance for individual flying stones Shallow hole blasting to …
Deep hole blasting Deep hole blasting is the blasting method that uses drilling equipment to drill deeper holes as the charge space of mining explosives. The deep hole blasting in open pit mine is mainly bench …
The radius of the crush zone formed by mining explosive blasting is typically 1.5–3 times the radius of the charge, and the radius of the fissure zone is approximately 10–17 times the radius of the charge (Dai 2013). Deep-hole blasting technology is mature, easy to organize, and widely used in coal mines.
The Datong Mine was a background to study the blast crush zone and drainage influence range following deep-hole blasting with holes laid in coal seams, which resulted in a 24% increase in gas flow ...
The safety distance of electric detonation mainly considers the safety distance between the blasting area and the emission sources such as high-voltage lines, radio stations and television stations. ... The hole should be deep enough to insert the detonator completely without exposing the explosive roll. After the detonator is inserted into the ...
Using the traditional cutting blasting technology in vertical shaft construction has some features, e.g. slows driving speed, gangue with large volume and throwing high.
Blasting safety involves assessing, controlling, monitoring, and managing risk throughout the entire process of a blast, from site selection to clean-up. ... Blast geometry: including hole size(s), hole depth, drill pattern, …
Safety Precautions While Blasting. Here are the key safety considerations BICs and blasting crews should consider while shooting the blast: A red flag will mark the blast area for everyone's safety. Evacuate all …
The components of a drill rig are (1) the rig itself, which supplies the power to mobilize, drill rock, and remove the drill cuttings from the hole; (2) the mounting; (3) the drill steels or drill string; …
A case study was conducted using 258 blasting data samples to develop these models. Key factors influencing flyrock were identified: blast hole burden distance, maximum instantaneous charge, and rock brittleness index. Using these factors, a flyrock possibility assessment chart was created to enhance the safety of small-scale mining operations.
Flyrock represents a significant and fundamental challenge in surface mine blasting, carrying inherent risks to humans and the environment. Consequently, accurate prediction, minimization, and identification of the factors influencing flyrock distance are imperative for effective control and mitigation of its destructive consequences. Machine learning and artificial …
2 Deep hole dispersed cut blasting model and its mechanism analysis 2.1 Deep hole dispersed cut blasting technology As mentioned previously, this paper proposes a deep hole dispersed charge cut blasting technology to improve the excavation eciency of deep hole cut blasting. This tech-nology's core is represented by changing the traditional
In order to prevent the impact of blasting vibration on the TBM, the safety distance is larger than 30 m. The hole-by-hole delayed detonating network with electronic detonator is selected with MS-3 (50 ms) different for each borehole, and the delay time is selected with MS-5 (100 ms). ... The deep-hole blast model used in this study ...