Application in Mining

Mine Lencschecy (Hungarian)

A transformer-box on level +97m with temporary insert of steel-arch in a distance of 2m have been constructed and between the arch, wire mesh are installed. Through the spraying of concrete with quality B200 in a profile of 4000mm cross-section a wall of 20cm thickness 40m lengths was build.

Mine Recsk I (Hungarian)

On level - 900m a loadingstation with a combination of top-anchoring, mats and wet-mixed shotcrete by a rock-temperature of 52°C has been constructed. The concrete- mixture under expenditure of Andesit-gravel has been try pre-mixed above ground and was feed through a drainpipe to the working place. From concrete quality B280 a wall of 40cm thickness and about 8m lengths was build.

Mine MÈV IV (Hungarian)

A machine-room for an underground shaft-hosting-equipment has been constructed with a combination of top-anchoring, steel-mat and wet-mixed shotcrete. The dimensions of the permish red-sand-stone undermining rooms are 18m lengths, 12m width and 10 m high. Half of the high of the hollow-space, it has found a clay-layer of about 30cm thickness and therefor the hollow-space was deformed accordingly. In the rock, by a temperature of 60°C, a supporting wall of 25cm thickness has been built, the concrete with gravel has had the quality of B280.

Mine Tatbanáya, Pit XXI/A (Hungarian)

Construction of a loading-station under an outlet of ventilation-slop-pit. The original construction with steel arch in a distance of one meter fence-grids between the arch, become for the final construction the concrete with gravel and has a quality of B280. The concrete has mixed on construction-side. The construction length comes up to 76m with a thickness of 25cm.

Mine Gyöngyös, adit XIII (Hungarian)

The task was the spraying of an impermeable isolation-layer for an underground oil-reservoir and in a bypass-tunnel. The reservoirs - from a cross-section of 4000mm - have constructed with concrete-form-stones type VA40. The sprayed isolation-layer with a thickness of 8cm, sprayed on a mesh-wire of 8mm, had the concrete quality B280 with gravel. In the bypass-tunnel from a cross-section of 6,6m² a construction from wooden-barring in a trapeze-cross-section of a length of 64m has been installed. The constructions become reinforced by a steel-mat and a sprayed-concrete-wall, thickness 10cm, from concrete-quality B280.

Mine Putnok (Hungarian)

In Oligozän a slop pit from 19m² breakout-cross-section of a length of 760m with open archway-profile craved-heading and with steel-arch from a distance of 1 m timber-casing has been constructed. Thirteen months after the heading the final supporting has completed. By the dismantling of the casing on different places it was find out, that in spite of the gently heading, already one year later, signs of over-break in a substantial extent become visible. A group of professional and researcher of the Borsodar-Mining comes after an expert report on side, and with a corresponding control-calculations to the decision, that the removal of the mountain-debris and the belated rear-filling with shotcrete becomes to lavish. For that reason therefore a wall out from shotcrete with the quality of B200 and steel-mats in a thickness of 15cm above the untouched TH-arcs and casing brought in. By the concrete-spraying injection-pipes has been installed, after the final construction of the slop-pit the rear-filling with cement-mortar was carried out through pipes.

Mine Markushegy (Hungarian)

A Water-dam from 11m in a slop-pit has carried out in a concrete-spraying-system. A closed archway-profile, with provisional fixed steel-arch in a distance of 40cm and watertight concrete of the quality B400, a concrete-wall of 40cm thickness was carried out. In a drifting slop-pit with provisional fixed steel-arch in a distance of 60 - 80cm with grids-elements in between was installed and with a complex advance-heading system from experts of Oroszlàny developed. The assemblies of the sprayed concrete are in dependence of the steadiness of the surrounding rock and the concrete quality had a variation in between of B280 and B400. Several times during the interior works it comes to the construction of crossings with two to three sections and with large cross-sections of 25m² to 30m² and the breakthrough accordingly. During the rhythm of the development-works the interior works with shotcrete in the pit-hollow-space in the mine Markushegy was to continue.

Mine Tatabánya XIV/B (slop-pit) (Hungarian)

In course of maintenance-work of a constructed section with steel-arch of a length from 230m become a long-life spraying-concrete of a quality B280.

Mine Majk (Hungarian)

A tunnel with a cross-section of 3500mm, installed with steel-arch and wooden casings catch fire. Of a length of 90m a shell of fire-resistant concrete for firefighting has constructed. The hermetically sealed concrete-layer prevent the air-supply to the fire-place. Therefore it was possible to damp the fire. After the firefighting the shell of spraying-concrete has taken over the interior function.

Ajka, slop Armin (Hungarian)

After the blast road-advance the wet-mixed-shotcrete technologies come into function. In a cross-section of 3200mm a provisional construction with steel-arch in a distance of 1 to 2m has brought in. Later on, a wall of wet-mixed-shotcrete in a changeable and in advance calculated thickness has produced. Problems rise up by the ups and downs through the blast of the break outs in the cross-section. On one side by the hump up of the steel-arch, where the pre-stress of the steel-arch was not successful, and on the other side, an unwanted fluctuation in the sprayed-concrete layer.

Nagyegyháza (Hungarian)

The task is a final construction with wet-mixed-shotcrete for a slop-pit with a closed archway-profile of a length of 1660m. The slop-pit had a cross-section of 16m² and a slop of 12°. The main-haulage-drift - coal floor +29m - and the belt-section of the lower bed in a length of 220m has constructed in the final stage, also with the wet-mixed-shotcrete technology. With drilling from collecting-holes and use from chemicals the problems with the disturbing water-flow in the slop-pit cut be solved. The provisional works of the called hollow-space exist from steel-arch and steel-mats. The sprayed concrete manufactured in a mixer above surface and transported in container to side.

Komló, pit - Anna (Hungarian)

In course of maintenance work a constructed road with steel-arch from 3000mm cross-section become grid-elements and after that a concrete layer with gravel from Andesit-gravel has spread on.

Dorog, pit XXI (Hungarian)

A new slop-pit for mining of a coal-reserve, recumbent in a column, has been built. In course of this work at the crossings with two sections with a diameter of 4000mm respectively 5000mm, a sprayed concrete layer of 40m length was brought in.

Tokod (Hungarian)

In Tokod a drift-way by trapeze-cross-section, on floor +132m, has been built by rail and grid-casing, a sprayed-concrete construction was brought in. From time to time self-inflamed occur in this section. This sprayed-concrete-layer caused in his construction-function also as fire-protection.

Mine Walsum, Extension of shaft-bottom no.4 (Germany)

First time in German Mining a drift-way in concrete without steel-arch on mine Walsum has been constructed. The dimensions of the drift-way are 4,4m high, 6,5m white the inside cross-section are 23,9m² , the breakout cross-section is 26,5m² and the advance-length is 3m. In this area the dominant rock was from slate-clay. The task is a long-life and reliable construction with a high load-supporting and nearly without steel-construction-elements. The opening up drift-way shall use over many years. By the conventional construction-method it must be calculated that through the breaking down influence, sooner or later, the arch-construction will corrode and the load-supporting will be strong effected. Therefore steel-construction-elements shall not use normally. After an advance of three meters, the uncovered top-region and the upper part of the face of heading has break down. Later on, a concrete-layer from two centimetre thickness has brought in and practically the rocks become sealed. The blast rocks are cleared and the uncovered drift-way connections and the part under the face of heading has been reinforced by a concrete-shell. After that the miner saves the top with anchors 2,6m long and structural-steel-mats. Approximately 30 to 50m behind the face of heading the final concrete construction, at least 15cm thickness, was brought in. To avoid, that by a possible breaking down influence of the heading, part of the concrete-shell chips off, therefore the concrete gets armouring out from grid-arch and structural-steel-mats. This grid-arch makes it possible to keep the drift-way profile. Results of measurements confirm, the former calculated values are fulfilled and the wet-mixed-shotcrete system in the thin-stream technology reached a reliable and a long-life construction with a remarkable high-load supporting.