Study On The Supporting Technology Of T-junction Of The Fully Mechanized Top Coal Caving Longwall Face In Pitched Thick Seams

Different from the delaying slope coal seam, there is difficultly supporting particular complexity in the T-junctions of the fully mechanized top coal caving longwall face in pitched thick seams because of existence of triangle top coal in tail T-junction and triangle floor in head T-junction. Due to existence of that complexity, the tail triangle top coal easily falls and also grows up to high,and the head triangle floor easily slips ,therefor supports fail,which making lost control of"supporting-surrounding",and it also brings great danger to the whole face and limits the application of that mining method.So it is essential to study on supporting technology of T-junction of the fully mechanized top coal caving longwall face in pitched thick seams.The supporting complexities of T-junction of the fully mechanized mining and top coal caving longwall face in pitched thick seams are mainly as follow:1. Roof falls are likely to occur at the joints of the longwall face as above and paralled panels because of the horizontal bedding of the coal seam.Especially, the strata pressures are very high due to the pressure interection in areas of the T-junction and the coal mining face, the present of ground pressure and its control turn to complex.2.As angle of the face greater,the top coal turns around along slop when it falls down to the gob.In the T-junction,supporting turns more difficult due to forming crack of coal piller by ground pressure.3. The tail triangle top coal offen easily falls if support by sigle prop with a long gird bar, and then the top coal slips down ,which may hurt workers and damage the machines.At the same time,the stength of supporting lowere,and the supporting spaces smaller,it is hard for equipment-haulage,man-traffication and ventilation.Also it is easy for the gas to mass and to fire,which greatly dangers the production. 4. There is the easily sloping triangle floor area in the head T-junction. If it were damaged,then it would slipe,meanwhile the damaging and sloping area grows up, so it makes supports heavily slipping and dumping,and roof-caving accident may happen.And in this area, there are machines,in addition ,float coal and water that makes the working environment turns bad and the work turns hard.The T-junctions are the fieled of accident often occurring and managing gweak in practice, frequently aboundent of man-force,money and resourse are consumed there.therefor, the T-junction supporting is a important joint of the face production. The study on T-junction of supporting technology of the full mechanized top coal caving longwall in the pitch and thick coal seams can improve the production and the benefit,also can amend the working environment.The this is based on the particularity and the complexity of the T-junction supporting of longwall minging in pitch and thick coal seams,and it is a styemic study on the subject through physical simulating experement, numerical modeling and ground pressure behaviours by practice.The enginering case shows that the T-junction supporting technology studied works well,but there also exist problems.The programs solving to them have been discussed in the thesis.And the programs have been made use of in the period of reforming support design and improving T-junction supporting technology.