Open-pit mining is the near-surface extraction of mineral raw materials in open pits. It is characterized by stepped slopes, overburden movement, and high-volume material flows. In addition to classic methods such as drilling and blasting, increasingly precise, low-vibration hydraulic solutions are used today to loosen rock, deconstruct structures, and modify installations. In particular, hydraulic wedge splitters and concrete demolition shears are used in selected work steps, for example in secondary breakage, in the removal of concrete foundations, or in sensitive areas where blasting is to be avoided.
Definition: What is meant by open-pit mining
Open-pit mining refers to the extraction of deposits at the surface, i.e., without coverage by massive soil layers or overburden rock. It is used for lignite, ore minerals, industrial minerals, natural stone, and construction raw materials. Extraction proceeds along benches and berms that advance step by step. Overburden (barren rock) is separated from the ore and either dumped or used for backfilling and later landscape shaping. Operations include geotechnical engineering, pit dewatering, haul roads, conveying technology, processing, and occupational safety. The goal is to extract raw materials economically, safely, and in an environmentally compatible manner while preparing the area for subsequent reuse.
Mining chain in open-pit mining: From the deposit to processing
The process chain in open-pit mining follows a clear sequence that varies by commodity and geology, but always aims at controlled material loosening and efficient hauling.
- Exploration and planning: geological modeling, slope design, water management concept, traffic and safety planning.
- Preparatory measures: removal of overburden soils, temporary dewatering, preparation of roads and ramps.
- Material loosening: drilling and blasting or the blasting-minimized use of hydraulic wedge splitters for controlled loosening and secondary breakage.
- Loading and transport: wheel loaders, excavators, dump trucks, or conveyor belts move the material to processing.
- Processing: crushing, screening, classification; in natural stone, selection by grain size; in ores, further separation where applicable.
- Dismantling and reclamation: stepwise dismantling of temporary structures and shaping of landscape elements.
Soft vs. hard rock
In unconsolidated material and lignite, shovel and bucket-wheel solutions dominate. In hard rock, drilling and blasting are common. Where vibrations, noise, or flyrock must be minimized, rock wedge splitters support precise splitting along predrilled holes.
Blasting-minimized alternative in sensitive areas
Near plant buildings, transport infrastructure, or sensitive slopes, low-vibration splitting methods are used to open blocks, break down oversize, and secure berm edges. This reduces dust and noise emissions and facilitates quality control of the slope surface.
Rock reduction in open-pit mining without blasting
Controlled size reduction is crucial for loadability, conveying performance, and crusher utilization. Using hydraulic rock and concrete splitters, high splitting forces are generated in the borehole and rock bodies are separated along planes of weakness. This allows oversize blocks to be divided into conveyable pieces or disturbing ribs at the pit floor to be trimmed without introducing additional vibration.
Typical applications
- Secondary breakage of oversize at the loading face
- Slope smoothing and removal of protrusions (scaling)
- Preparation of block stone in natural stone extraction
- Localized rock excavation near sensitive installations or utility lines
Benefits for operations and the environment
- Low-vibration and controlled, protecting adjacent structures
- Reduced flyrock and low noise input
- Fine control of size distribution for even crusher utilization
Secondary breakage, block management, and loadability
A homogeneous stream of pieces reduces bottlenecks at the primary crusher. With rock wedge splitters, blocks are divided so that target edge lengths and weights do not exceed the load capacity of the bucket, dump truck, or conveyor systems. This lowers the share of manual rework and minimizes the risk of crusher jams.
Process notes
- Adjust borehole spacing and depth to layer thickness, joint pattern, and target grading
- Select the splitting sequence to create free edges and relieve stresses in a controlled manner
- Coordinate interfaces with processing regarding target size distribution
Infrastructure in open-pit mining: Construction, operation, and dismantling
Conveyor bridges, crusher stations, belt lines, retaining walls, silos, and plant buildings characterize every open pit. These structures must be adapted, relocated, or dismantled at the end of mining. For concrete demolition and special demolition, different tool-side solutions are used depending on the material and installation situation.
Foundations, columns, and massive concrete components
Concrete demolition shears enable targeted grabbing, crushing, and cutting off of concrete parts including reinforcement. In combination with hydraulic power units, high closing forces can be controlled safely. For prestressed or particularly massive sections, a preliminary splitting step with hydraulic wedge splitters is recommended to reduce cross-sections and define crack paths.
Steel and hybrid structures
Belt gantries, conveyor bridges, and pipelines are dismantled section by section. hydraulic shears and steel shears cut profiles and plates, while Multi Cutters cut cables, fittings, and reinforcement. For tanks in plant yards or the processing area, cutting torches are used in structured cutting sequences. These tasks fall under gutting works and cutting as well as special demolition.
Special deployments during ongoing operations
When facilities remain partly in service, quiet, low-spark, and controlled methods are required. Planning of cut sequences, load transfer, and lifting points is combined with suitable tool selection to minimize hazards and keep downtimes short.
Safety, emissions, and environmental protection in open-pit mining
Occupational safety has priority. Measures against dust, noise, and vibration are standard. Hydraulic wedge splitters and concrete demolition shears contribute by enabling controlled, localized interventions. Legal requirements on emissions, nature conservation, groundwater, and waste management differ by location; they should be integrated into planning and execution at an early stage without anticipating specific cases.
Minimizing emissions
- Water mist and localized extraction at crushing and cutting points
- Use of quieter, low-vibration methods near sensitive assets
- Control material flow to reduce transfer points and drop heights
Reclamation and subsequent use
After extraction, the landscape is shaped. This includes securing slopes, removing temporary structures, and backfilling pit sections. During dismantling, concrete demolition shears, hydraulic shears, and, where needed, hydraulic wedge splitters are used to free foundations, crush concrete, and separate steel. An early-planned sequence shortens project duration and improves material recyclability.
Planning, quality assurance, and documentation
Robust planning links geology, equipment, tool selection, and maintenance. Quality metrics such as particle size distribution, conveying availability, and deconstruction rate support operational control. Hydraulic tools are supplied via hydraulic power packs; their output should be matched to cylinder and shear requirements and checked regularly. Documented cutting and splitting sequences facilitate repeat processes and increase occupational safety.
Material properties and tool selection in open-pit mining
Rock and concrete behave differently. Jointed granite, limestone, or sandstone can be effectively split along existing planes of weakness. Heavily reinforced concrete, by contrast, requires a combination of pre-splitting and final reduction with concrete demolition shears. For steel structures, steel shears are appropriate, while Multi Cutters are used for cables, lines, and reinforcement. Tool selection is guided by strength, toughness, degree of reinforcement, and accessibility.
Classification by application area
- Rock excavation and tunnel construction: selective loosening work, slope stabilization, secondary breakage
- Natural stone extraction: controlled pre-splitting, block size control
- Concrete demolition and special demolition: foundation removal, plant dismantling
- Gutting works and cutting: selective removal of steel and concrete components
- Special operations: work in sensitive zones with higher requirements for vibration and noise control