Compressive and tensile failure of inclined well bores and determination of in situ stress and rock strength

It is very important to study the pristine stress field in Civil, Mining, Petroleum engineering as well as in Geology, Geophysics, and Seismology. There are various methods of determination of in-situ stress in rock mass. However, hydraulic fracturing techniques is the most convenient method to determine and interpret the test results. Based on an hydraulic fracturing stress measurement campaign at an underground liquefied petroleum gas storage project which locates in ZhuHai, China, this paper briefly describes the various uses of stress measurement, details of hydraulic fracturing test system, test procedure adopted and the concept of hydraulic fracturing in arriving at the in-situ stresses of the rock mass.

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Rock Overstressing in Deep Tunnel Excavation of Pahang-Selangor Raw Water Transfer Project

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.802.16 ◽

2015 ◽

Vol 802 ◽

pp. 16-21 ◽

Cited By ~ 2

Author(s):

Romziah Azit ◽

Mohd Ashraf Mohamad Ismail ◽

Sharifah Farah Fariza Syed Zainal ◽

Norzani Mahmood

Keyword(s):

Rock Strength ◽

Stress Measurement ◽

In Situ Stress ◽

Water Transfer ◽

Stress Factors ◽

Raw Water ◽

Tunnel Excavation ◽

In Situ Stress Measurement ◽

Assessment Approach

Tunneling under high overburden and in-situ stress may cause tunnel instability because of rock overstressing. Evaluating overstressing in deep hard rocks is crucial to minimize excavation risks. The excavation of the Pahang-Selangor Raw Water Transfer Tunnel is evaluated in this study. A potential overstressing problem is expected at a tunnel depth more than 500 m. Therefore, the possibility of rock overstressing is assessed based on the evaluations of in-situ stress measurement, rock strength, and actual observations during the tunnel excavation. An analytical method is used to analyze the behavior of the tunnel under high overburden stress based on rock strength and tangential stress factors. The empirical assessment approach to the observation of actual overstressing appeared to be valid for the prediction of overstressing. These approaches facilitate the reasonable prediction of tunnel behavior under different rock conditions, support systems, and overburden stresses, which serve as useful tools in the observational design and construction method of long and deep tunnels.

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Determination of in situ stress profiles through hydraulic fracturing measurements in two distinct geologic areas

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts ◽

10.1016/0148-9062(89)91444-7 ◽

1989 ◽

Vol 26 (6) ◽

pp. 637-645

Author(s):

W.S. Whitehead ◽

J.M. Gatens ◽

S.A. Holditch

Keyword(s):

Hydraulic Fracturing ◽

In Situ Stress ◽

Stress Profiles

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Point-deflection method for in-situ stress determination of advanced lithographic masks

Microelectronic Engineering ◽

10.1016/s0167-9317(02)00544-0 ◽

2002 ◽

Vol 61-62 ◽

pp. 271-276 ◽

Cited By ~ 4

Author(s):

N. Tang ◽

R.L. Engelstad ◽

E.G. Lovell

Keyword(s):

In Situ Stress ◽

Stress Determination ◽

Lithographic Masks

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APPLICATION OF GUIDELINE CHARTS IN DECISIONMAKING ON WELL TRAJECTORY AND MUD WEIGHT PROGRAM

The APPEA Journal ◽

10.1071/aj00031 ◽

2001 ◽

Vol 41 (1) ◽

pp. 609

Author(s):

X. Chen ◽

C.P. Tan ◽

C.M. Haberfield

Keyword(s):

Stability Analysis ◽

Case Studies ◽

In Situ Stress ◽

Wellbore Stability ◽

Material Strength ◽

Stress Regime ◽

Wellbore Instability ◽

Well Trajectory

To prevent or minimise wellbore instability problems, it is critical to determine the optimum wellbore profile and to design an appropriate mud weight program based on wellbore stability analysis. It is a complex and iterative decisionmaking procedure since various factors, such as in-situ stress regime, material strength and poroelastic properties, strength and poroelastic anisotropies, initial and induced pore pressures, must be considered in the assessment and determination.This paper describes the methodology and procedure for determination of optimum wellbore profile and mud weight program based on rock mechanics consideration. The methodology is presented in the form of guideline charts and the procedure of applying the methodology is described. The application of the methodology and procedure is demonstrated through two field case studies with different in-situ stress regimes in Australia and Indonesia.

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