RU2277153C1 - Method for high broken-profile bench slope protection against landslide - Google Patents

Abstract

FIELD: mining, particularly to consolidate or to protect pit sides against landslide during pit operation.

SUBSTANCE: method involves laying transversal members connected to ropes along slope, wherein the ropes are fixedly secured to anchors located in upper bench berm; drilling inclined wells extending to bench slope; installing next anchor along lower edge of upper berm and drilling next inclined well cluster. Suspending net to bench slope and pulling down ropes from upper berm through drilled inclined wells so that the first rope ends extend from bench slope; lowering the rope ends to lower berm and securing thereof to transversal members arranged above the net, wherein the transversal members are installed beginning from lower berm; tightening the ropes and fastening the second rope ends to anchors.

EFFECT: increased operational safety and decreased labor inputs for bench slope consolidation.

1 ex, 2 dwg

Description

The invention relates to mining and can be used to maintain or strengthen prone to shedding ledges of the quarry during its operation.

A known method of strengthening career slopes. The method of strengthening is as follows. Two deviated wells are drilled from the upper berm of the ledge: one before reaching the escarpment surface of the ledge, and the second outside the sliding surface. A roller is installed at the intersection of the wells. From the lower berm of the ledge, a well is drilled perpendicular to an inclined well drilled outside the sliding surface until it intersects with it. A roller is also installed at the intersection of the wells. A rope is passed through the wells, pulling it through the rollers, while one end of it is brought to the surface of the lower berm of the ledge, and the other to the surface of the slope of the ledge. The ends of the rope are connected to metal plates, the rope is tensioned. Installation and tensioning of the rope is carried out until the approach to the limiting contour of the quarry on the lower ledge (RF Patent No. 2049916, application No. 4847225/03, filed July 3, 1990, published December 10, 95, bull. No. 34).

This method, in principle, allows to increase the stability of the ledge as a whole, but is not applicable to strengthen the entire surface of the slope from shedding and outfalls of rock blocks. Due to the limited berms, quarries with high ledges of a broken profile will not have enough space to drill the first deviated well, and if the sliding surface is located outside the ledge, it is impossible to drill the second. The proposed well drilling and the location of the rollers at the intersection of these wells, as well as the technical difficulty in pulling the ropes through the rollers makes practical use difficult, especially for high 35-45-meter ledges.

The closest in technical essence and the achieved result is the method described in the construction of the coating for strengthening quarry slopes. The method includes laying transverse elements along the slope of the ledge on the cables, rigidly fixed to the anchors on the upper berm of the ledge. The method is implemented as follows: on the upper platform of the slope, anchors fix the cables, lay them on the slope; on the ropes fix the cross-members, consisting of separate links articulated with each other; then a concrete coating is applied to the slope (Auth. St. USSR No. 1745817. Coating for reinforcing career slopes, application No. 4792007/03 of 11/16/89, published on 07/07/92).

This method of strengthening is not applicable in quarries with high ledges of a broken profile. When applying concrete to the reinforcing elements of the coating (cables, cross-members, consisting of links) located on a slope 30 meters or more in height, there is a difficulty in holding it. Given that the reinforcement work is carried out in quarries with a slope angle of 75 degrees or more, the use of concrete will require the development of a new spray technology for high ledges and special equipment for supplying mortar to the slope surface, which will increase the labor costs for these works.

The aim of the invention is to increase the safety of work and reduce labor costs to strengthen the slopes of high ledges broken profile.

This goal is achieved by the fact that in the method of strengthening the slopes of high ledges of the broken profile from shedding, including laying transverse elements along the slope of the ledge on the cables, rigidly fixed to the anchors on the upper berm of the ledge, previously deviated wells are drilled from the upper berm of the ledge until the ledge reaches the ledge, a flexible grid is hung on the slope, cables are passed through the wells, and the laying of transverse elements is carried out from the lower berm.

Preliminary, from the upper berm of the ledge, drilling of deviated wells before reaching the ledge of the ledge allows for a simpler and safer way to secure the structure on the ledge of the ledge.

Attaching a flexible grid to the escarpment of the ledge, which protects the escarpment from shedding of rocks, leads to the safety of work on the lower berth of the ledge, since according to the technological scheme for mining the quarry, the lower berth contains mining equipment and people who drill blast hole wells and charge explosive wells Surveying survey of a blasting passport. The hinged grid between the escarpment of the ledge and the cross-members protects the escarpment from weathering and shedding of rocks, since the geological structure of the small blocks of the fractured ledge does not exceed the size of the mesh cell.

Fastening the cross-members (plates) from the lower berm allows you to increase the safety of work, since the installation of cross-members and cables is carried out on a horizontal platform, and not at the height of the slope of the ledge. Installation in place of the metal structure so that the cables are opposite the anchor, and then securing them can significantly reduce the time for strengthening work, and therefore reduce labor costs.

Fastening the flexible mesh to the slope by pressing it with the cross members using the cables fixed to them by pulling them and rigid fastening by the anchors installed on the upper berm prevents the slope from falling out of large pieces of rock, which ensures the safety of work, as the mining equipment located on the lower berm and people, according to the technological scheme of mining the quarry, are not at risk of falling under the dump, which can lead to deaths and serious damage to mining equipment.

Figure 1 shows a section of a ledge broken line profile. Figure 2 shows a top view of a ledge with structural elements for implementing the method, where

1 - ledge;

2 - drilling rig;

3 - anchor (pile), pipe with a cross section of 220 × 5 mm;

4 - deviated wells;

5 - a flexible grid, for example a grid "netting", 1 layer, section 2 × 40 mm;

6 - wire rope with a cross section of 30.5 mm;

7 - cross-members, channel 300 × 100 mm;

8 - connection of the cable to the cross member.

Concrete implementation example

Currently, mining is underway at the quarry. The need to strengthen the escarpment of the ledge is due to the presence of fractured and weathered rocks in it, weakening the strength properties of the escarpment. It is necessary to maintain the ledge and thereby prevent its further deformation.

The following initial data were taken: ledge height - variable, 35-45 m, ledge slope angle - 75-90 degrees, transport loads were taken into account.

Work to strengthen the ledge as follows.

At the very beginning, preparatory work is carried out: the berms are cleaned mechanically and the ledge slope frill. After a mechanized frill, the individual remaining overhangs, “visors”, are manually removed by a team of mountain slope drifters and they clean the berm cloth with mechanized vehicles using special equipment.

On the upper berm of ledge 1, three meters from the lower edge, a drill rig 2 is installed and a well is drilled under an anchor (pile) 3 with a depth of 4-5 meters. Set anchor 3 and concrete it. Having departed from the lower edge on the length of the drilling rig 2, perpendicular to the upper edge of the ledge 1, three deviated wells 4 are drilled on the same berm one meter later until the ledge reaches the slope. To set the angle of drilling of deviated wells 4, the slope of the ledge 1 is previously divided in height into equal sections.

After 3-5 meters along the lower edge on the ledge 1, 3 meters from the lower edge, a drilling rig 2 is installed and a well is drilled under the second anchor 3 (of the same depth) and installed. In a similar manner, the second cluster of deviated wells is drilled. A flexible net 5, for example a netting net, is hung on the escarpment of the ledge 1.

From the upper berm into the inclined wells 4, cables 6 are passed, one end of which is led to the slope of the ledge 1 and lowered to the underlying berm. On the underlying berm, fasten the cables 6 to the cross-beams 7 (at a distance from the ends of the cross-arms corresponding to the even distribution of loads along the slope) by welding 8. The cross-beams 7 are placed on the slope of the ledge 1, stretch the cables 6 until they are fully pressed to the surface and immobility and fastened to anchors 3 using welding. Anchors on the upper platform of the ledge allow a less laborious way, without additional special technical means, to ensure the fastening of the retaining elements. There is a retention and a flexible grid, which is located under the cross members. The number of sections is determined by the length of the reinforced area according to the actual position of the ledge.

As a result of implementing the method on a ledge, a fixed structure is obtained. The proposed method allows you to most effectively strengthen the escarpment of the ledge during the operation of the quarry by reducing labor costs, cost less material to strengthen, and as a result, reduce the cost of maintaining the escarpment, ensuring the safety of reinforcing and mining operations for mining the quarry.

Claims (1)

A method of strengthening slopes from shedding, including laying transverse elements along the slope of the ledge on cables, rigidly fixed to the anchors installed on the upper berth of the ledge, characterized in that to ensure the strengthening of the slopes with high ledges of the broken profile after the installation of anchors on the upper berth, inclined wells are drilled until the exit on the ledge slope, after which along the lower edge of the upper berm the next anchor is installed and the next cluster of deviated wells is drilled, then the grid is hung on the ledge slope and from the top she berm into the drilled inclined wells pass cables, one ends of which lead to the escarpment of the ledge, lower them to the underlying berm and fix to the transverse elements placed on top of the mesh, laying which are starting from the lower berm, after which the cables are tensioned and the second ends of the cables are secured to anchors.

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