Roof Bolting Anchoring Performance Research on the Entry under the Gob of Close-Distance Coal Seam

Yang, Yongjie; Huang, Gang; Ji, Haiyu

doi:10.1155/2022/8991574

Cited by 3 publications

(3 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…On the basis of the difficulties in roadway support and support principles, [23][24][25][26][27][28][29] in view of the large area roof fall disaster of the broken surrounding rock of No. 11103 fully mechanized caving roadway under the double gob, the Usteel + anchor + prop coupling support structure is used to bear the broken surrounding rock, resist the top pressure, and prevent the U-shaped steel from appearing weak section under the eccentric load conditions of coal pillar stress concentration and gob stress reduction, which reduces the bearing capacity.…”

Section: Analysis Of Coupling Support Structurementioning

confidence: 99%

Coupling support technique for coal roadway under double gobs in close coal seams

Wu,

Nan,

Chen

et al. 2024

Energy Science & Engineering

View full text Add to dashboard Cite

In the process of lower coal roadway support under double gobs in close coal seams, there are problems such as the whole destruction of the lower coal seam and the intermediate strata, the thin roof of the lower coal roadway with the smaller support space, the upper rock of the lower coal roadway without anchor bearing layer, the roof falling, the anchor cable offing, and so on. On the basis of the engineering background of No. 11103 haulage roadway in Fenxi coal mine, the research methods of theoretical modeling analysis, numerical simulation analysis and field engineering test are comprehensively adopted. In this paper, the layout of the roadway with floor insertion in the lower coal seam, the distribution characteristics of surrounding rock deviatoric stress, the control principle of broken surrounding rock and the coupling support method of shed–cable–prop are systematically studied. The study shows that many measures are needed to ensure the stability of the surrounding rock in the strong mining roadway of the lower coal seam. The lower coal seam roadway section was modified from the original rectangular section to adopt an arched section to counteract the broken roof. The staggered position of the lower coal seam roadway layout was modified from the original coal roadway position to a coal–rock roadway, so as to avoid the area of high deviatoric stress in the coal pillar and the area of crushed coal body, and to leave an effective support space for the roof. The support scheme of the lower coal seam roadway was improved to use anchor cable and single prop to support the weak section of U‐type steel shed with local coupling, and realize unequal force coupling by adjusting the size of the force at different coupling points. In the field monitoring the deformation of the roadway is small, and the support effect is good.

show abstract

Section: Analysis Of Coupling Support Structurementioning

confidence: 99%

Coupling support technique for coal roadway under double gobs in close coal seams

Wu,

Nan,

Chen

et al. 2024

Energy Science & Engineering

View full text Add to dashboard Cite

show abstract

“…Some scholars have studied the problems arising from close-distance coal seam mining (Cheng et al; Ning et al 2020; Yang et al 2022). The bearing structure characteristics of overlying strata in the overlying goaf in short-distance coal seams mining are the main factors inducing roof dynamic disasters.…”

Section: Introductionmentioning

confidence: 99%

“…After the upper coal seam mining, the strength and stress distribution of the roof in the lower coal seam mining area changes, and the roof effective control is the key to the lower coal seam mining, so it is very important to study the roof breaking characteristics in the close distance coal seam. Some scholars have studied the problems arising from close-distance coal seam mining (Cheng et al;Ning et al 2020;Yang et al 2022). The bearing structure characteristics of overlying strata in the overlying goaf in short-distance coal seams mining are the main factors inducing roof dynamic disasters.…”

Section: Introductionmentioning

confidence: 99%

Roof breaking characteristics and mining pressure APPEARANCE laws in close distance COAL seams

Liu

Ren

et al. 2022

Energy Exploration & Exploitation

View full text Add to dashboard Cite

In order to obtain lower coal seam mining of roof breaking characteristic and the law of mine pressure appearance in the close distance coal seams, this paper takes working face 6101 of a mine as the engineering background, and studies the roof breaking characteristics and pressure law in close distance coal seam through theoretical analysis, numerical simulation and engineering verification, which provides the basis for roof control in lower coal seam mining. The results show that the maximum failure depth of 4# coal seam mining on floor is 8.28 m. The lower coal seam mining roof forms a “loose-block” structure, and the main roof fracture step distance is 44.61 m. The UDEC simulation shows that the initial weighting intensity of 6# coal seam is large, and the first weighting distance step is about 40 m. The hydraulic support with the highest working resistance should be chosen based on the roof pressure analysis, and the weighting is frequent. The hydraulic support with higher working resistance should be selected through the analysis of roof pressure, some control measures should be taken to strengthen the organization and management, and prevent the occurrence of roof disasters. The roof is effectively controlled through engineering verification. The study further recognizes the laws of mining pressure appearance in lower coal seam of close distance coal seam, and provides experience for similar mine mining.

show abstract

The evolution law of deviatoric stress and asymmetric control technology in roadways during panel mining through overlying residual coal pillars

Tian,

Ye,

et al. 2024

Sci Rep

View full text Add to dashboard Cite

Close-distance coal seams (CDCS) are widely distributed, and the layout of the upper and lower panels can be divided into “=” type and “+” type. The “+” superposition of upper and lower coal pillars in CDCS caused strong mine pressure, but there are few studies on the panel crossing residual coal pillars (RCP) when the upper and lower coal seams are “+” type layout. In view of the special spatial position (“+” type layout), this paper takes the typical panel 4-301 of a particular mine as the project indagation background and studies mining and crossing the overlying coal pillars by dint of field measurement, numerical simulation, indoor test, and engineering application. Compared with vertical stress or horizontal stress alone, the indexes of deviatoric stress and plastic zone can reflect the failure evolution of surrounding rock more comprehensively. Hence, this paper analyzes the expansion form of the plastic zone and the variation law of deviatoric stress before and after mining influence in the underlying mining roadway. The research results show that: (1) There is a sub-peak zone of deviatoric stress under the RCP. The deviatoric stress is bimodal in the range of 9 m below. After the peak value decays to 7.4 MPa, it changes to a single peak located in the area directly below the middle of the RCP. (2) The maximum plastic zones of the roof and two ribs of the roadway below the RCP are 3.4 m and 5 m, respectively. The crest value of deviatoric stress reaches 10 MPa. As the distance between the panel and the RCP decreases, the shape of the high deviatoric stress area presents the evolution law from the “ellipse” of the roof → the “crescent” of two ribs → the “cochlea” of the tips of the ribs. (3) When the mining of the underlying panel is 10 m, 0 m, or − 10 m away from the RCP (without passing through the RCP). The crest value of deviatoric stress within 5–10 m in advance of the roadway increases in turn. However, the peak value is significantly reduced when it is − 20 m away from the RCP (through the RCP). The crest value of deviatoric stress of two ribs decreases in turn along the panel rib → section coal pillar rib → solid coal rib. Based on this, the underlying 45 m of the RCP is divided into area I (10 m), area II (overlapping area 20 m), and area III (15 m) based on the degree of disturbance. And propose the technical scheme of asymmetric combined control in different zones by using asymmetric channel steel truss anchor cable for the top-ribs of areas I and III, and top-ribs asymmetric channel steel truss anchor cable + door-type support in area II. On-site project practice shows that the partitioned control technology successfully resisted the roadway instability and failure caused by the dynamic-static superimposed stress disturbance under the RCP and realized the primary support of the sectional coal roadway. The conclusion provides technical support and scheme design for the partitioning support of roadways under similar “+” type cross‐panels.

show abstract

Roof Bolting Anchoring Performance Research on the Entry under the Gob of Close-Distance Coal Seam

Cited by 3 publications

References 22 publications

Coupling support technique for coal roadway under double gobs in close coal seams

Coupling support technique for coal roadway under double gobs in close coal seams

Roof breaking characteristics and mining pressure APPEARANCE laws in close distance COAL seams

The evolution law of deviatoric stress and asymmetric control technology in roadways during panel mining through overlying residual coal pillars

Contact Info

Product

Resources

About