Abstract：The concept and theory of stress shadow were introduced. The particle discrete element model was constructed with the fluid-solid coupling calculation. The distribution of the induced stress due to the stress shadow around a single hydraulic fracture was simulated and analyzed. The analysis shows that the mainly effect of stress shadow is the increasing of the minimum horizontal stress，and the effect has dual character. The effect of initial horizontal stress on hydraulic fracture was analyzed using the established model. The result shows that the induced stress due to the stress shadow was increasing with the increasing of the ratio of the initial horizontal principal stress，and it was more disadvantageous to the dehiscence and development of the new fractures. When the hydraulic pressure in the initial fracture was closed to or greater than the maximum initial horizontal stress，the propagation direction of the hydraulic fracture caused by the infusion holes would be changed，and it was conductive to the formation of a complex fracture network.
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2016, Vol. 35 
