【摘要】 滚压破岩为冲击压碎和剪切碾碎的复合过程。表征其破碎效果的参量是侵入深度h和岩石自然破碎角φ。h取决于外载荷和岩石坚固性,在一定的载荷条件下,h虽能表示破坏岩石的难易程度,但不充分,因为塑性岩石h可能很大,但破碎下来的岩体并不多。φ则是较单纯的量,它与载荷和压头的几何形状无关,而与岩石性质和自由面条件(数目和形状)有关,可用它表征岩石的可破坏性。本文在讨论滚压破岩中,以φ为基本参量,以试验数据为基础,建立了抛物线破碎面积和体积模型,从力平衡和能量守恒定律出发,分析了滚压破岩各参量之间的关系,确定载荷与各参量之间的函数形式。更多还原

【Abstract】 Rock fracture by rolling disc-cutter is a compound fracture process combined with the impacting compression and the shear crushing. The fracture effects may be characterized by two parameters as the depth of penetration h and the fracture angle of rock φ The value of h depends on the load-up condition and the hardness of rock. On certain load-up condition, the crushing strength of rock may be shown in term of A,however, it is considered as unsufficient. The value of h would be propably high in plastic rock , while amount of fracture are not quite as much. As to the angle φ, a more simple quantity, is unrelated to both the load-up condition and the shape of bit but looks like related to rock characters and condition of free surface of rocks. It may also be a characterizing index of crushing strength of rock.As a review of studies on rock fracture by rolling disc-cutter, this paper deals with the theoretical analysis about fracture process. Taking the angle φ into account as a fundamental parameter and in view of the counter-balance of forces and the law of energy conservation,the models of parabolic area and volume fractured has been set up on the basis of experiments. Also, a functional relation between loads and other parameters has been formulated as follows:whereP-vertical force (kg);Kd-coefficient of conversion;[σe]-uniaxial compressive strength of rock (kg/cm2);φ-rock fracture angle (deg);γ-radius of wear ci cle (mm);θ-a half of the angle between cutting edges (deg);R-cutter radias (cm);h-depth of cutter penetration (cm);αd-specific energy of rolling fracture (kg·m/cm3).Those formulae above indicate that the vertical force is a function of both the rock fracture parameters (as [σc] etc) and the geometrical parameters of disc-cutter as R, θ and r.更多还原