RU2490461C1 - Method to mine thick steep deposits of unstable ores - Google Patents

Abstract

FIELD: mining.SUBSTANCE: method to mine thick steep deposits of unstable ores includes separation of an ore body into floors, and floors - into horizontal or flat layers, mined in a descending order, extraction of ore within layers by stopes, filling of the mined space with hardening materials, tunnelling of stopes of the second and further layers under the filling mass. When tunnelling stopes of the second and further layers in their sides represented by an ore massif, they drill blast holes, where they install anchors from materials that are easily damaged when tunnelled, for instance, wooden ones, anchors are installed in rows arranged at the different distance from soil of the stope, the length of anchors in rows is accepted as more than the depth of area propagation in the stope sides, and within this area the ore is damaged to the moment of start of works for filling of the stope with hardening materials under action of the reference mining pressure, at the same time anchors in the row are installed with a shift in direction parallel to the axis of the stope, relative to the anchors in the adjacent row at the 0.5 of distance between anchors.EFFECT: improved safety of mining works, increased speed of stopes tunnelling and higher quality of filling works.2 dwg

Description

The invention relates to the mining industry and can be used in underground mining of powerful steeply dipping ore deposits characterized by low strength characteristics of ores.

There is a method of developing powerful steeply dipping deposits of unstable ores (Patent RU No. 2309253, published October 27, 2007), including dividing the ore body into horizontal or slightly inclined layers worked out in ascending order, excavating the layers with horizontal or slightly inclined treatment openings, and filling the openings with hardening materials. The disadvantages of this method are the increased danger of sewage treatment associated with the collapse of the roof and sides of the openings, as well as the significant cost of securing the openings and laying the worked out space. This is explained by the periodic, as the layers are mined, deformation of the undermined ore mass, associated with incomplete filling of the worked out space with filling material, compaction of the filling mass in the process of hardening, and cleaning operations in the layers. Due to the increase in the degree of disturbance of the undermining ore mass, the transition to the mining of each new upstream layer is accompanied by an increase in the risk of mining and production costs.

A known method of developing steeply falling ore bodies (Patent RU No. 2209972, publ. 08/10/2003). This method includes dividing the ore body into floors, and floors into horizontal or slightly inclined layers, worked out in a descending order. In the layers are starting preparatory workings. Ore excavation within the layers is carried out by horizontal or slightly inclined treatment openings, passable from starting preparatory workings. Snapshots after their full-length are laid with hardening materials. As starting workings, drifts or orts are used. The disadvantages of this method when developing powerful steeply dipping deposits of unstable ores are the increased danger of treatment and significant costs for fixing treatment openings.

A known method of developing powerful steeply dipping deposits of unstable ores (Patent RU No. 2405108, publ. 11/27/2010). This method, adopted as a prototype method, includes dividing the ore body into floors, and floors into horizontal or slightly inclined layers, worked out in a descending order. Excavation of ore within the layers is done by sagging. The developed space is laid with hardening materials. Ends of the second and subsequent layers pass under the filling array created during mining of the above layers.

The disadvantages of this method when developing powerful steeply dipping deposits of unstable ores are: increased risk of mining due to the high intensity of spontaneous collapse of rocks and ore from the sides of the entry of the second and subsequent layers located under the filling array; low penetration rate of the entry, associated with the need to clean the rock mass that collapsed from the sides of the entry and “frills” of the side surfaces of the entry before filling and closing the sides of the entry with a special tightening; low quality of filling operations, which is associated with the presence of openings on the sides and on the ground of openings of destroyed ore.

The technical result of the proposed method for the development of powerful steeply dipping deposits of unstable ores is to increase the safety of mining, increase the speed of penetration of openings and improve the quality of laying works.

The technical result is achieved in that in a method for developing powerful steeply dipping deposits of unstable ores, including dividing the ore body into floors, and floors into horizontal or slightly inclined layers mined in a descending order, excavation of ore within the layers with openings, laying of the worked out space with hardening materials, sinking of the openings the second and subsequent layers under the backfill array, when drilling the penetrations of the second and subsequent layers in their sides, represented by the ore mass, drill holes in They install anchors made of materials that are easily destroyed during penetration, for example, wood, anchors are installed in rows located at different distances from the entry soil, the length of the anchors in the rows is greater than the depth of distribution in the sides of the entry area, within which the ore is destroyed by the time the laying starts approach with hardening materials under the influence of reference rock pressure, while the anchors in the row are set with an offset in the direction parallel to the axis of the approach, relative to the anchors in the inter row at 0.5 distance between the anchors.

The essence of the proposed method for the development of powerful steeply dipping deposits of unstable ores is illustrated by the schemes presented in figure 1 and figure 2.

Figure 1 presents a schematic diagram explaining the location on the side of the entry, passed through the 2nd and subsequent layers, anchors and the area of destruction of the ore mass under the influence of reference rock pressure.

Figure 1: 1 - ore mass; 2 - filling array created as a result of filling up the worked out space (completed passages) with hardening materials; 3 - entry to the laying of its hardening materials; 4 - anchors; b is the width of the sunset 3; a - the width of the sunset adjacent to the sunset 3; h is the thickness of the layer (height of entry); ABC - the area of destruction of the ore mass in the side of the entry 3 under the influence of reference rock pressure; S is the length of the anchor; d is the depth of propagation in the sides of the embedment area, within which the ore is destroyed by the time the work on laying the embedment with hardening materials under the influence of reference rock pressure formed above the edge of the ore mass begins; z is the distance between the anchors in the row; x is the distance from the top row of anchors to the entry soil.

A method of developing powerful steeply dipping deposits of unstable ores is as follows.

The ore body is divided into floors, and the floors into horizontal or slightly inclined layers worked out in a descending order. Excavation of ore within the layers is done by sagging. The worked out space (completed passages) is laid with hardening materials. Snaps of the second and subsequent layers pass under the filling array.

When driving the penetrations 3 of the second and subsequent layers (Fig. 1), holes are drilled in their sides represented by the ore mass, in which the anchors 4 are installed. For the manufacture of anchors, materials, for example wood, are easily destroyed during the penetration of the drillings by combines or using blasting .

Anchors are installed in rows located at different distances from the entry soil. Figure 2 shows three rows of anchors. The length of the anchors in the rows is taken to be greater than the depth of distribution in the side of the embedment area, within which the ore is destroyed by the time the work begins on laying the chamber with hardening materials under the influence of reference rock pressure forming in the side of the embedment above the edge of the ore mass. So in the upper row of anchors, located at a distance X from the soil of the sunset (figure 2), the length of the anchors S take more than d.

Anchors in a row set with an offset in the direction parallel to the axis of the entry, relative to the anchors in an adjacent row at a distance Z / 2 between the anchors (figure 2).

A feature of mining the second and subsequent layers in comparison with mining the first (upper) layer is an increased concentration of stresses in the zones of reference pressure that are formed in the sides of the openings above the edge parts of the ore mass. This is due to the hovering over the worked out space of the worked out layer of the filling array created during mining of the above layers. Under the influence of increased stresses in the zone of reference pressure, the ore mass in the sides of the openings is destroyed, which is the reason for spontaneous collapse of the ore into the openings.

The installation on the sides of the openings, represented by the ore mass, of anchors longer than the distribution depth in the side of the openings of the area within which the ore is destroyed by the time the work on laying the chamber with hardening materials begins, eliminates spontaneous ore collapse from the sides of the openings.

The installation of anchors made of materials, such as wood, which are easily destroyed during penetration, allows mining to be carried out without reducing the speed of penetration.

Installing anchors in rows with offset anchors in adjacent rows by 0.5 distance between the anchors allows you to achieve the maximum effect of hardening the sides of the castings with a minimum number of anchors.

The depth d (Fig. 1) of the distribution in the sides of the embedment area, within which the ore is destroyed by the moment the work on laying the embedment by hardening materials under the influence of reference rock pressure formed above the edge of the ore mass, begins, is determined in each case using well-known mine methods laboratory or analytical studies.

The parameters a, b, h, S, z and x are determined using known methods in the design of the technological scheme for mining the ore body, taking into account the influence of geological and mining factors.

Using the proposed method allows to increase the safety of mining, to increase by 10-15% or more the speed of penetration of openings, to improve the quality of laying works. Improving the safety of work is associated with the exclusion of spontaneous collapse of ore mass from the sides of the openings. The increase in the rate of entry penetration is due to the decrease in the volume of work to clean up the entries from the ore mass and the “frill” of the side surfaces of the entries before performing filling operations. Improving the quality of filling works is associated with the exclusion of spontaneous collapse of the ore mass from the sides of the openings and a more complete laying of the worked out space with hardening materials.

The inventive method is intended for use in underground mining of powerful steeply dipping ore deposits characterized by low strength characteristics of ores. In the Russian Federation, this method with significant social (security) and economic effect can be used in the development of rich iron ore deposits of the Belgorod group: Yakovlevsky, Gostischevsky, etc.

Claims (1)

A method for developing powerful steeply dipping deposits of unstable ores, including dividing the ore body into floors, and floors into horizontal or slightly inclined layers mined in a descending order, excavation of ore within the layers by fillings, filling the worked out space with hardening materials, drilling of the second and subsequent layers under the filling array , characterized in that during the penetration of the second and subsequent layers, in their sides, represented by the ore mass, drill holes in which they are installed Woodworkers made of materials that are easily destroyed during penetration, for example, wooden ones, are installed in rows located at different distances from the entry soil, the length of the anchors in the rows is greater than the depth of spread in the sides of the entry area, within which the ore is destroyed by the time the work on laying the entry hardens materials under the influence of the reference rock pressure, while the anchors in the row are set with an offset in the direction parallel to the insertion axis, relative to the anchors in the adjacent row by 0.5 distance Niya between anchors.

Images