岩石Π型断裂韧度剖面的预测研究

Study on fracture toughness profile prediction of rock mode Π

水力裂缝的起裂、扩展和转向主要受岩石Π型断裂韧度的影响,岩石断裂韧度参数的获取对水力压裂施工设计有重要的影响。然而,直接测量岩石断裂韧度具有费用高、可用岩心数量有限、转向时间长等缺点,因此,本文在直切口巴西圆盘方法的基础上发展了Π型岩石断裂韧度新型测量法,并在在测井资料的基础上建立了求取岩石断裂韧度剖面的数学模型,为后续压裂施工设计提供了纵向上连续的准确的岩石断裂韧度数据。

Thecrack initiation and excend of Hydraulic fracture are mostly influenced by fracture toughness of rock mode Π.Rock fracture toughness parameters is of great significance for design of hydraulic fracturing.But the direct measurement method of rock fracture toughness is expensive,available to a limited number of cores and requires too much time.Therefore,Straight Brazilian disc method in this article is developed to measure the rock model Π fracture toughness.The mathematical model of rock fracture toughness profiles are established on the basis of logging data.Thus providing continuous and accurate fracture toughness data in lengthways gradient for the design of hydraulic fracturing.