Static elastic modulus

Indices are dimensionless parameters derived from various mechanical and physical properties of the tablet blend and resulting compacts. Mechanical properties typically measured include indentation hardness (kinetic and static), elastic modulus, and tensile strength (10,11). Physical properties include particle size, shape, and size distribution, density (true, bulk, and tapped), flow properties and cohesive properties. 

Bending Strain Static elastic modulus (Young s Modulus, i.e., the slope of the stress-strain curve in the elastic region) Crystalline morphological transitions... 

Compressive strength ratio -Ratio of static elastic modulus Ratio of dynamic elastic modulus... 

The influence of joints on static and dynamic elastic modulus was investigated based on the data provided in Table 4 and Table 5. Regression analysis was done for the data on ratios of static and dynamic elastic modulus of plaster of Paris (POP) specimen. Plaster of Paris-cement mix specimen and mixed data of plaster of Paris and Plaster of Paris-cement mix specimen. The curves were plotted for the ratio of static elastic modulus and dynamic elastic modulus for all the three groups of data. The plotted curves are shown in Figure 24 to Figure 26. Figure 24 shows the experimental values of ratio of static elastic modulus versus ratio of dynamic elastic modulus for POP specimens. Figure 25 shows the trend of ratio of static elastic modulus versus ratio of dynamic elastic modulus for POP-cement mix specimens. The plot of ratio of static elastic modulus versus ratio of dynamic... 

It is clear from the analysis shown in Figure 25, Figure 26 and Figure 27 that the trends of ratio of static elastic modulus versus ratio of dynamic elastic modulus for POP specimens and POP-cement mix specimen are always below the line of comparison. This indicates that the anisotropy of the specimen is influencing the dynamic elastic modulus more than the static elastic modulus. The low strain experiments on the POP and POP-cement mix models also indicate that the effect of joints is more predominant for the sample material of higher strength than the lower strength material. 

The rocks with planar anisotropy exhibit the highest strength in the direction perpendicular to the anisotropy and the lowest at an inclination of 30°-45° with the plane of anisotropy in jointed samples. The anisotropy of the specimen influences the dynamic elastic modulus more than the static elastic modulus... 

The anisotropy of the specimen is influencing the d5mamic elastic modulus more than the static elastic modulus. 

In this paper the compressive strength/elastic modulus of the jointed rock mass was estimated as a function of intact rock strength/modulus and joint factor. The joint factor reflects the combined effect of joint frequency, joint inclination and joint strength. Therefore, having known the intact rock properties and the joint factor, jointed rock properties can be estimated. The test results indicated that the rock mass strength decreases with an increase in the joint frequency and a sharp transition was observed from brittle to ductile behaviour with an increase in the number of joints. It was also found that the rocks with planar anisotropy exhibit the highest strength in the direction perpendicular to the anisotropy and the lowest at an inclination of 30o-45o in jointed samples. The anisotropy of the specimen influences the dynamic elastic modulus more than the static elastic modulus. The results were also compared well with the published works of different authors for different type of rocks. 

The structure of the venous walls is basically similar to that of the arterial walls. The main difference is that they contain less muscle and elastic tissue than the arterial walls, which raises the static elastic modulus two to fourfold [49]. Because the venous walls are much thinner than the arterial wall, they are easily collapsible when they are subject to external compressions. 

In these expressions, tg is the reaction time at gel point, s and t are the static scaling exponents which describe the divergence of the static viscosity, nO 6 , at trgelation mechanism has been discussed on the basis of several models based on the percolation theory (for review, see ref 16), that provide power laws for the divergence of the static viscosity and the elastic moduli. Characteristic values for the s, t and A exponents are predicted by each of these models (Table I). 

Dynamic elastic modulus, regarded herein as a mechanical property, will be treated along with static elastic modulus and the plastic properties in Chapter 12. Properties included for discussion in this chapter are listed in the following five subsections. 

The static (mechanical) elastic modulus is determined in the linear part of the elastic deformation at the strain-deformation diagram of the sample at static load. The difficulty in determining the static elastic modulus is in the fact that the deformation before the fracture is only microns and a precise apparatus is required. The static elastic modulus may be measured at strength tests (compression, bending, tensile), and, of course, the sample will be broken. In reality, the measurement of the dynamic elastic modulus is more popular. 

Strength characteristics of carbon materials almost do not depend on temperature—at least at temperatures of A1 reduction, so the temperature dependence of strength for carbon cathode materials more likely has academic interest. It is well known that the static elastic modulus (determined at mechanical testing) is sufficiently lower compared with values obtained via ultrasonic methods. 

There are two types of elastic moduli. First, there is the static elastic modulus that is measured from the stress-strain response of the solder when subjected to tension or compression testing (Ref 25). The second type is referred to as the dynamic elastic modulus and is measured by the passage of sound waves through the material (Ref 26). In the latter case, because sound wave propagation in a solid is based upon atomic vibrations that are very rapid, inelastic deformation is largely ehminated from the material response. Therefore, the modulus is determined from nearly pure elastic deformation. On the other hand, the static modulus is sometimes preferred when calculating plastic strain because it accounts for aU deformation leading up to the yield stress as defined by the 0.2% offset criterion. 

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