- Normalized Uniaxial Compressive Strength Data For Mac Pro
- Normalized Uniaxial Compressive Strength Data For Mac Air
Influence of lithophysal geometry on uniaxial compression of tuff-like rock Manisha Chawla University of Nevada, Las Vegas Follow this and additional works at: Repository Citation Chawla, Manisha, 'Influence of lithophysal geometry on uniaxial compression of tuff-like rock' (2007). Following the discussion on the paper, we would like to add our comments on a few issues. In this study, the uniaxial strength is taken to be the compressive strength of cylinder tested without removing the end friction at the loading platens because, in practice, the uniaxial strength of concrete is obtained in this manner. Strength denoted with. are normalized over the uniaxial cylindrical compressive strength. Ttt. is the normalized. Determination and Validation of Parameters for riedel-Hiermaier-thoma. Yu-Qing Ding., Wen-Hui Tang, Ruo-Qi Zhang, and Xian-Wen Ran. National University of Defense Technology, Changsha - 410 073, China. 1a) was illustrated. The strength dependence of the normalized Hoek–Brown constant (m in) (Fig. 1b) were also calculated rock types. By analyzing the data of five different rock types they found a correlation between the normalized material constant (m in) and the uniaxial compressive strength of the rocks (r ci). The m i value of.
Laboratory testing has been undertaken to study the variability of the responses of rock specimens prepared with varying length-to-diameter ratios when subjected to uniaxial compressive strength testing. Two rock types were used in the experiment; these are granite and grano diorite, known to be massive and homogenous rocks. Specimens prepared at length-to-diameter ratios ranging from 1.5 to 3 were subjected to uniaxial compression in a Material Testing System (MTS) at a constant stroke rate, to evaluate the effects on the rock strength parameters, such as the peak strength, modulus of elasticity and Poison?s ratio (Í). The results of this testing have demonstrated that the modulus of elasticity of the two rock types did not change while the peak strength also did not vary significantly. The grano diorite and granite rocks indicated slight decreases on peak strength with increasing specimen length-to-diameter ratio. Significant variations were, however, demonstrated in the Poisson?s ratio (Í) achieved by the two rock types: The Poisson?s ratio (Í) decreased significantly with increasing specimen length-to-diameter ratio: a decrease of approximately 75% from the smallest specimen length-to-diameter ratio (1.5-to- 1 ratio) to the largest (3-to-1 ratio) for both rock types was apparent. This observation has a significant effect for determining important parameters such as Bulk Modulus (K) and Shear Modulus (G) of the two rock types tested, which are important parameters when performing numerical modeling. Significant benefits for use of the results to normalize specimen length-to-diameter ratio standards for uniaxial compressive strength testing applications has been assessed and presented
The standard test method for unconfined compressive strength testing of intact rock core specimens and the standard practice for preparing rock core specimens and determining dimensional and shape tolerances are provided in ASTM D 2938-86 and ASTM D4543-01, respectively. Procedures, loading rates, specimen perpendicularity, flatness tolerances, minimum specimen diameter, specimen length-to-diameter ratio, etc. are provided by these standards.
A laboratory test program was set up to investigate the effects on the strength parameters of two different rock types when subjected to unconfined compressive strength testing prepared at varying length-to-diameter ratios. The two massive and homogenous rock types used were grano diorite and granite. Uniaxial compression tests were primarily conducted to obtain the intact rock unconfined compressive strength (UCS), Young?s Modulus (E) and Poisson?s ratio (Í) parameters. Besides providing an important data point for determining a failure locus (i.e. Mohr-Coulomb envelope) they are useful for defining parameters needed for numerical modeling. The loading conditions (stroke rates) during compression were also investigated to understand the effect of this variable on the mechanical behaviour of the rock. All specimens were drilled, cut and trimmed (in conformity with ASTM D4543-01) in the rock mechanics preparation laboratory of the Department of Mining Engineering, Queen?s University at Kingston, Ontario, Canada.
Normalized Uniaxial Compressive Strength Data For Mac Pro
Influence of Penetration Rate and Indenter Diameter in Strength Measurement by Indentation Testing on Small Rock Specimens
Abstract
Indentation testing has been developed as an unconventional method to determine intact rock strength using small rock specimens within the size of drill cuttings. In previous investigations involving indentation testing, researchers have used different indenter stylus geometries, penetration rate (PR) and specimen sizes. These dissimilarities can restrict applications of this method for strength measurement and lead to non-comparable results. This paper investigates the influence of indenter diameter (ID) and PR on indentation indices for carbonate rocks to provide objective comparison and application of the existing correlations. As part of this research, several indentation tests were conducted using different IDs and PRs. The laboratory test results showed that indentation indices can be affected by ID while PR has only minor effect on the indentation indices. Thus, a normalizing function was presented to reduce the dependency of test results to ID. Verification of the findings with independent data confirms the suitability of the suggested normalizing function in determining the rock uniaxial compressive strength using testing data obtained from various IDs and PRs.
Normalized Uniaxial Compressive Strength Data For Mac Air
- Indentation test;
- Drill cutting;
- Indenter diameter;
- Penetration rate;
- Normalized indentation modulus;
- Uniaxial compressive strength;
- Wellbore geomechanics