STUDY ON ROCKMASS DETERIORATION AND CHANGES OF POROSITY AND PERMEABILITY IN DOUBLE-POROSITY MEDIUM UNDER HYDRAULIC FRACTURE BASED ON DAMAGE THEORY
ZHAO Wanchun1，AI Chi1，LI Yuwei1，GUO Boyun2
(1. Key Laboratory of Education Ministry for Enhance Oil Recovery，Daqing Petroleum Institute，Daqing，Heilongjiang 163318，China；2. College of Oil Engineering，University of Louisiana，Lafayette 70504，USA)
Abstract：Firstly，according to the mechanism of rock damage of hydraulic fracturing for oil reservoir，considering the changes of matrix porosity and micro-cracks volumes after loading on rock，the tensor damage variable of rock damage is defined by using the changes of matrix porosity and microfracture volumes，and the rock damage deterioration model of hydraulic fracturing is obtained based on damage theory. Secondly，assuming the dynamic evolution of microfracture of the process of hydraulic fracturing satisfies with the Logistic fork standard model，the microfracture dynamic evolution model is established based on the damage theory and according to energy conservation principle of hydraulic fracturing，the internal relation among the volumetric strain，medium porosity and damage variable of the process of rock damage evolution is determined. Finally，the model of matrix porosity and the evolution of permeability tensor of Microfracture for hydraulic fracturing rock is established. Taking the well named 29–3，4 in Jilin oil field for example，the traditional method and the new one are implemented as modules into finite element software to simulate productivity to verify the advantage of new model. The comparison result shows that the new model is more suitable for practical situation.
赵万春，艾池，李玉伟，郭柏云. 基于损伤理论双重介质水力压裂岩体劣化与孔渗特性变化理论研究[J]. 岩石力学与工程学报, 2009, 28(S2): 3490-3496.
ZHAO Wanchun1，AI Chi1，LI Yuwei1，GUO Boyun2. STUDY ON ROCKMASS DETERIORATION AND CHANGES OF POROSITY AND PERMEABILITY IN DOUBLE-POROSITY MEDIUM UNDER HYDRAULIC FRACTURE BASED ON DAMAGE THEORY. , 2009, 28(S2): 3490-3496.
