Study On The Deformation Mechanism Of The Surrounding Rock In Rectangular Laneway And Its Application In Wangcun Coal Mine

The failure law and support technology research of rectangular roadway under complexconditions is an important issue of coal mine construction and production. To carry out arectangle surrounding rock deformation mechanism study has important theoreticalsignificance and practical engineering value In this paper，studys on the surrounding rockdeformation mechanism and control technology of the laneway on the background of WangCun coal mine by theoretical analysis, numerical simulation, site monitoring as well aslaboratory.The main conclusions are as follows:⑴The basic law of the rectangle surrounding rock deformation and failure were studied.The results showed that when the span-height ratio is constant,with the lateral pressureincreasing,the stress continues to increase in rectangular laneways corner, corner rock causesshear failure, the crack or shear failure is occurred in the roof, composite-layered roof andboth sides and its displacement gradually increas. When the lateral pressure coefficient isconstant, with the span-heigh ratio increasing, the corner stress increases firstly and thendecreases.The displacement of both sides increases, while the displacement of the roof withcomposite-layered roof decreases.⑵Analyzed the mechanical mechanism of the deformation and failure about thesurrounding rock in rectangular laneway was studied systematically. The results show that thestability of a single layer roof depends on elastic modulus, Poisson’s ratio and thickness-spanratio, while the stability of the composite layer roof related with its consolidated elasticmodulus and Poisson’s closely whose deformation and failure include four phases which is theadjustment of structural carrying capacity, the weakness of structural overall stiffness,the stress adjustment and the structural instability.The displacement of coal sides in rectangularlaneways inculdes the crush zone, plastic zone and the elastic zone.It provided thedistribution of load in coal sides’ limit equilibrium region, was established about the coalplastic zone formula of the width and horizontal displacement and was derived about themaximum failure depth of the backplane when both sides is squeezed.(3)Studied the extent of failure and the form of failure in different sides pressure.As theplatts balance arch theory is inadequate in the practical engineering application,this paperstudys on the stablity of the backplane and the balance arch shape of the single layered roofand composite layered roof in different sides pressure.According to the features of rock stressstate by ellipse laneways distributing after rectangular laneways rock failure,it was derived onmaximal span-height ratio of elliptical maximum inscribed rectangle laneways.Based on therelationship of elliptic surrounding rock stress with the axial ratio,the paper establish theoptimal span-height ratio formula of rectangular laneways by elliptical maximum inscribedrectangle laneways which provides a basis for rectangular laneways’ design.(4)The field test study on deformation and failure of surrounding rock of rectangulartunnels was launched. Aiming at the destruction of the deformation and failure of surroundingrock circle theory in the study of the existing rectangular roadway surrounding rock of deeppoint, the method of multi-point displacement meter and sight combination is used, the mainrectangular roadway surrounding rock deformation and failure scope of Wangcun mine fieldmonitoring. Through the collation and analysis of many data, established the buried depth,roof lithology and span and two for damage range of single and multiple factors predictingformula considers rectangular tunnel.(5)The transport of Wangcun mine13503working face crossheading roadway as test,using the above research results to the field of surrounding rock of the original supportscheme and parameters were optimized. The results show that, the mechanism of deformationand failure of surrounding rock of roadway surrounding rock based on rectangle to determinesection size and support parameters are reasonable and feasible.