To solve the technical problems in controlling surrounding rock of gob-side entry retaining deep and close distance coal seams under goaf, deformation failure characteristics goaf were analyzed this paper. Basic support inside roadway high-strength prestressed wire meshes, beam cable anchor, reinforcement single hydraulic with hinged roof roadside high-water material filling structure proposed....

This paper presents a data-driven method for automatic building reconstruction from raw airborne laser scanner data. The method utilises a TIN-structure that is calculated into the point cloud. The parameters of every TIN-mesh are mapped into a 3D trianglemesh parameter space, which is then analysed using a cluster analysis technique. By analysing the clusters, significant roof planes are deriv...

In order to explore the stability of overburden rock and development height water flowing fractured zone in roadway filling mining, based on movement deformation mechanism rock, mechanical analysis failure was carried out, model main roof beam established, ultimate span limit deflection fracture were deduced. Combined with basis for judgment developing is given this paper. Taking a coal mine ba...

With the gradual increase of coal mining intensity, many pillars need to be left near stope. The stability composite structure and their overlying strata determines safety whole stope surface. This paper conducts uniaxial compression tests on coal-rock structures with same lithology height ratio finds structure’s mechanical properties failure characteristics have greater discreteness. Combining...

This article presents the application of a self-excited acoustic SAS system for non-destructive testing (NDT) roof-bolt housings in laboratory and real mine conditions. The proposed with filtering mechanism was applied to J64-27 composite anchors. conducted tests allowed successful confirmation usefulness detection rod defects, damage coupling anchor rock mass stress state itself. eliminating e...

INTRODUCTION The medial maxillary sinus roof is a ridge formed by the superior margin of the maxillary sinus antrostomy. The posterior wall of the maxillary sinus is always included in operative fields. OBJECTIVE To perform a radiologic study assessing the utility of the medial maxillary sinus roof and the posterior wall of the maxillary sinus as fixed landmarks for providing a safe route of ...

Aiming at the problems of difficult support mining roadway under goaf close distance coal seam, obvious large deformation, and long-term continuous deformation surrounding rock, an advanced bolt-grouting system is proposed. The can effectively solve problem from design system, construction monitoring evaluation realize intelligent support. Based on actual engineering background 29204 working fa...

This study aims at the robust automatic detection of buildings with a gable roof in varying rural areas from very-high-resolution aerial images. The originality of our approach resides in a custom-made design extracting key features close to modeling, such as e.g. roof ridges and gutters. In this way, we allow a large freedom in roof appearances. The proposed method is based on a combination of...

Solid backfill coal mining technology has been widely applied in coal seams that are at risk of hard roof. Using actual measured strain–stress curves of the backfill body and the similarity theory, this study designed and employed four experimental models for physical simulation, corresponding to roof-controlled backfilling ratios of 0%, 40%, 82.5% and 97% using the geological conditions of Fac...

Mines with exceptionally low-strength roof (UCS <3,500 psi and CMRR <40) are much more likely to struggle with roof falls than other mines. Weak roof is a particular problem for many room and pillar mines in the Midwestern and Northern Appalachian coal basins. Traditional roof support techniques are often not up to the challenge at these operations. This paper focuses on two mines, one operatin...