A Theoretical Explanation for Rock Core Disking in Triaxial Unloading Test by Considering Local Tensile Stress

• Autorzy: Huang H. , Fan P. , Li J. , Wang M. , Rong X.

Identyfikatory

DOI

10.1515/acgeo-2016-0068

• Języki publikacji: EN

Abstrakty

EN

Rock is a typical inhomogeneous material with a large number of flaws in different scales; the stress field of the rock in its elastic state consists of two parts: the elastic stress, which distributes uniformly in the entire region; and an additional stress, which only exists around the flaws. Theoretical expressions of the additional stress and local stress are derived based on the Maxwell model. Core disking which takes place under the condition that the axial stress is rapidly reduced while the confining pressure is kept unchanged is explained with a new method. Unloading duration’s effect on core disking is analyzed. A new criterion for core disking is presented based on attributing the core disking to the result of the exceedance of local tensile stress over the tensile strength. Based on our theoretical analysis and the conclusions from published resources, core disking is most likely to occur if the maximum principal stress is more than five to six times the tensile strength.

Słowa kluczowe

EN

flaws; local stress; core disking

PL

wady; naprężenie lokalne

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2016
• Tom: Vol. 64, no. 5
• Strony: 1430--1445
• Opis fizyczny: Bibliogr. 15 poz.

Twórcy

autor

Huang H.

• State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact, PLA University of Science and Technology, Nanjing, China

autor

Fan P.

• State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact, PLA University of Science and Technology, Nanjing, China

autor

Li J.

• School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, China

autor

Wang M.

• School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing, China

autor

Rong X.

• State Key Laboratory of Disaster Prevention and Mitigation of Explosion and Impact, PLA University of Science and Technology, Nanjing, China

Bibliografia

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