A construction method for excavating a wide cross section mining roadway with pillar in a space driving manner

Abstract

The present application relates to a kind of interval driving pillar type wide cross section recovery roadway excavation construction method, comprising the following steps: according to the size of recovery roadway section, when the cross section of recovery roadway is greater than 6.5m, it is divided into multiple small sections from left to right along the center line of recovery roadway in wide cross section recovery roadway excavation;S2, first interval excavation odd small section, after the completion of odd small section excavation, then excavate the remaining even small section, leave ore pillar in the recovery roadway of the remaining even small section, continue to excavate after point column rear section until along the ore body is excavated, finally form several point column under the protection of recovery roadway.The advantages are: through block excavation in turn, realize a small amount of parallel operation blasting, reduce the damage to surrounding rock and ore body, which is beneficial to the safe and efficient recovery of ore body.At the same time, the first excavated section can provide free surface and compensation space for the remaining section excavation, improve the blasting effect.

Description

Technical Field

[0001] This invention belongs to the field of mining technology, specifically relating to a construction method for excavating wide-section mining roadways with intermittent tunneling and pillar retention. Background Technology

[0002] Currently, the sublevel caving method is widely recognized as one of the best mining methods for mining thick ore bodies and has been widely used worldwide. The sublevel caving method divides the ore body into several stages, and then further divides each stage into several sub-sections using a retreat roadway. Mining is carried out segment by segment from top to bottom. No bottom structure for ore extraction is set at the bottom of each sub-section, and no pillars are left. Drilling, caving, and ore extraction are all carried out within the retreat roadway, making it safe and reliable.

[0003] In traditional sublevel caving mining methods, roadways with a cross-sectional width greater than 6.5m are generally referred to as large-section roadways. The existing construction method for large-section roadways involves excavating the full width in a single pass. While this method widens the roadway cross-section, allowing for uniform ore extraction by loaders and facilitating the use of large-scale mechanized production equipment, thus improving ore extraction efficiency, it also presents the following problems:

[0004] 1. After the wide cross-section mining roadway is excavated and formed, it is affected by ground pressure. Due to the large open roof area of ​​the wide cross-section roadway, there is a potential stability risk in the roof.

[0005] 2. Wide cross-section single-blast tunneling involves a large total amount of explosives in a single blast and a long cycle, which causes significant damage to the surrounding rock and ore body, and has a significant impact on safe and efficient mining.

[0006] 3. Wide cross-section blasting requires a large number of blasting holes per blast, making blasting operations and construction management complex and increasing safety hazards.

[0007] 4. When excavating a wide cross-section, each blast only has a single free face, resulting in a relatively poor blasting effect.

[0008] Cyclic advance and blasting operations are relatively inefficient. Summary of the Invention

[0009] The purpose of this invention is to provide a construction method for excavating wide-section mining roadways with intermittent tunneling and pillar retention, which can provide free face and compensation space for blasting ore extraction, is safe and reliable, can be applied to large-scale mechanized production equipment, and improves ore extraction efficiency.

[0010] The present invention discloses a construction method for excavating a wide-section mining roadway with intermittent tunneling and pillar retention, characterized by comprising the following steps:

[0011] S1, based on the size of the mining roadway cross section, when excavating a large-section mining roadway with a cross section span greater than 6.5m, it is divided into several small sections from left to right along the center line of the mining roadway.

[0012] S2, firstly, the odd-numbered small cross sections are excavated at intervals. Each individual cross section is excavated by blasting in one go according to the cut holes, auxiliary holes and peripheral holes, and free face and compensation space are provided for the remaining even-numbered small cross sections.

[0013] After the odd-numbered small cross sections are excavated, the remaining even-numbered small cross sections are excavated. In the mining roadway of the remaining even-numbered small cross sections, ore pillars are reserved. After the pillars are placed, the cross sections continue to be excavated until they are excavated along the ore body, and finally several mining roadways under the protection of pillars are formed.

[0014] Preferably, when excavating a wide cross-section mining roadway with a span of L m, the roadway is divided into five small sections from left to right along its centerline; sections I, III, and V are odd-numbered sections, and sections II and IV are even-numbered sections. After the odd-numbered sections I, III, and V are excavated, the remaining even-numbered sections II and IV are excavated. Pillars are reserved in the mining roadway where sections II and IV are excavated. Excavation continues on the sections behind the pillars until the excavation is completed along the ore body strike, ultimately forming a mining roadway protected by pillars.

[0015] Preferably, the dimensions of the reserved pillar are length * width = L / 10m * L / 10m.

[0016] The advantages of this invention are: This method divides a large cross-section into multiple smaller cross-sections using an intermittent, pillar-based excavation approach. Partial cross-sections are excavated first, followed by the remaining sections. After excavation, the vertical stress and displacement of the entire cross-section exhibit a peak-valley pattern, resulting in a more uniform stress distribution. This solves the stability problem of the roof of a large cross-section roadway after excavation. By excavating in blocks sequentially, multiple parallel blasting operations are achieved, reducing damage to the surrounding rock and ore body, which is beneficial for the safe and efficient mining of the ore body. Simultaneously, the first excavated cross-section provides a free face and compensation space for the excavation of the remaining cross-sections, improving the blasting effect. Attached Figure Description

[0017] Figure 1 This is a front view of the excavation section of a wide-section mining roadway with intermittent tunneling and pillar retention according to the present invention.

[0018] Figure 2 This is a cross-sectional view (A-A') of a wide-section mining roadway with intermittent excavation and pillar retention.

[0019] Figure 3 The diagram shows the peak-valley pattern of vertical stress across the entire cross-section after excavation.

[0020] Figure 4 The vertical displacement after excavation presents a peak-valley pattern with staggered curves. Detailed Implementation

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] like Figures 1-2 As shown, the present invention provides a method for excavating a wide cross-section mining roadway with a column-retaining type. The mining roadway has a wide cross-section with a span of L m. The wide cross-section roadway is located in the ore body 1 and within the ore body boundary 2. The excavation project of the wide cross-section roadway is divided into 5 small cross-sections from left to right along the center line of the mining roadway.

[0023] First, odd-numbered small cross sections (I, III, and V) are excavated at intervals. Each individual cross section is excavated by blasting through slotting holes, auxiliary holes, and peripheral holes in one go. The excavation of slotting holes, auxiliary holes, and peripheral holes is not based on existing technology and will not be described in detail here. This provides free surfaces and compensation space for the remaining even-numbered small cross sections, resulting in more explosive energy acting on the ore body for crushing and less explosive energy acting on the surrounding rock of the roadway.

[0024] After the odd-numbered small cross-sections are excavated, the remaining even-numbered II and IV small cross-sections are excavated. In the mining roadways of these remaining even-numbered small cross-sections, a pillar (3) is reserved. The dimensions of the reserved pillar are length * width = L / 10m * L / 10m. Excavation continues on the cross-sections after the pillars are placed until excavation is completed along the ore body strike, ultimately forming several mining roadways protected by pillars.

[0025] This invention employs a method of excavating first through a subset of odd-numbered small cross-sections, followed by the remaining even-numbered cross-sections. After excavation, the vertical stress and displacement across the entire cross-section exhibit a peak-valley pattern, as shown in the diagram. Figure 3 and Figure 4 Its stress distribution is more uniform, which solves the problem of the stability risk of the roof of the large cross-section roadway after excavation and shaping, and improves the blasting effect.

Claims

1. A construction method for excavating wide-section mining roadways using intermittent tunneling and pillar retention, characterized in that, Includes the following steps: S1, based on the size of the mining roadway cross section, when excavating a wide mining roadway with a cross section span greater than 6.5m, it is divided into multiple small cross sections from left to right along the center line of the mining roadway. S2, firstly, the odd-numbered small sections are excavated at intervals. Each individual section is excavated by blasting in one go according to the cut holes, auxiliary holes and peripheral holes, and free face and compensation space are provided for the remaining even-numbered small sections. After the odd-numbered small cross sections are excavated, the remaining even-numbered small cross sections are excavated. In the mining roadway of the remaining even-numbered small cross sections, ore pillars are reserved. After the pillars are placed, the cross sections continue to be excavated until they are excavated along the ore body, and finally several mining roadways under the protection of pillars are formed.

2. The construction method for excavating a wide-section mining roadway with intermittent tunneling and pillar retention as described in claim 1, characterized in that, When excavating a large-section mining roadway with a cross-sectional span of L m, it is divided into 5 small sections from left to right along the center line of the mining roadway; I, III, and V are odd-numbered small sections, and II and IV are even-numbered small sections. After the excavation of the odd-numbered small sections I, III, and V is completed, the remaining even-numbered small sections II and IV are then excavated. In the mining roadway where the even-numbered small sections II and IV are excavated, pillars are reserved respectively. The section behind the pillars is excavated until it is completed along the strike of the ore body, and finally a mining roadway under the protection of pillars is formed.

3. The construction method for excavating a wide-section mining roadway with intermittent tunneling and pillar retention as described in claim 1, characterized in that, The dimensions of the reserved pillar are length * width = L / 10m * L / 10m.

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