Short situation-description of mining in general

Over the past years, a technological breakthrough in the basic processes of underground coal mining in Hungarian has taken place, such as the widespread acceptance of high-productivity sharer-loaders and shield supports in long-wall face mining. The introduction of high-capacity automated haulage system and microprocessor equipped dispatch's centre in production, supervision and control covering the entire mine.

As a result of this measures, the output of cutting-out has a significant increase. With effort therefor, the new casing-support has introduced. A method, which fits into the complex system of drifting is very easily, nevertheless, the high output will be adjust to the drifting-machine and also other demand of the support will fully require. All these targets can fulfil with the new wet-mix shotcrete system for the driving of headings. This procedure of shotcrete system is different to the well-known conventional system. The corresponding research became support from the competent Hungarian authorities.

The mechanical numbers of characteristic of the shotcrete are changeable between the borders and controlled between this borders. This circumstance allows an optimal calculation and realisation of the chamber-structure. This method and the result of the extension a different quality of the surrounding rock and on the alteration will be adept in a flexible way. For this purpose of the method, special grid-elements has developed which made from a possible weld steel-wire out from a reinforced grid manufactured by a high performance machine. These special manufactured elements can use as flat-grids or after a deformity, as a room-grid. In this extension the grids - between the steel-arch and the anchoring - can use as a casing if such becomes into action. Against to the manufacturing of a monolitical steel-concrete-construction the grids are likely as a skeleton and allows thicker built-in layer. The characteristic of the wet-mixed-shotcrete system permits under application of the underground mining and usual breaking down materials as steel-arch, anchoring, steel-mats, grid's etc, a realisation of an extension-combination with high-possible effectiveness under the present circumstances.

For spraying the concrete, a special machine-system in a so called box of brick's system is at disposal. In actual practice the system is working very successfully. From this special machine-system it is always possible to install a production-chain as requested. A large scale of technological construction variants makes the operation of the wet-mixed shotcrete system possible in mining, by concrete works of High- and Underground construction, by finding a solution in special tasks for construction above ground, by reconstruction, rehabilitation and reinforcements of buildings where the benefits of higher load-increase are required.

Below you will find an introduction of using the system since 1975 in different Construction fields.