Tensile splitting

These tests are performed by loading the standard 6" x 12" cylinder by a line load perpendicular to its longitudinal axis. The tensile splitting strength in pounds per square inch (f ) can be defined as... 

For members subjected to bending, the value of the modulus of rupture % rather than tensile splitting strength f is used in design. The modulus of rupture is measured by testing to failure, plain concrete beams 6 in. square in cross-section having a span of 18 in. and loaded at two points, each 16 in. equidistant from the end supports of the beam (ASTM C-78). 

For negative normal stresses, a state of tension exists in the sample along the yield locns. This area is generally not measnred by direct shear cells, bnt can be measured by triaxial shear and tensile split cells. 

CEN EN 12390-6.2009. Testing hardened concrete - Fart 6 Tensile splitting strength of test specimens. Brussels CEN. 

Figure 6. Baolian temple was tensile splitting by Wenchuan earthquake.

Figure 7. The square building was tensile splitting at the hilltop.

DS3 Extensive cracks with tensile splitting and falling of the outer layer of a few bricks repairable damage Loss of wall integrity 70 % reduction of the maximum strength Ultimate strain in the infill... 

Physical properties (ASIM methods in parentheses) Gel time = 2-5 min hardness (D2240) = 49 Shore D (>90 Shore A) tensile strength (D412) = 2393 pounds per square inch (psi) ultimate elongation (D412) = 103% die C tear (D624 — 91) = 341 foot-pounds per inch (Ibf/in.) split tear (D3489 — 90) = 97 lbf/in. I g(DMA) = -50°C. 

Splitting tensile strength of cylindrical concrete specimens Microscopic determination of parameters of the air-void system in hardened concrete... 

The tensile strength of compacts [30] also provides useful information. Excellent specimens of square compacts are necessary to conduct the tensile testing. For this reason, a split die [31 ] (Fig. 2) is used to make compacts that are not flawed. The split die permits triaxial decompression, which relieves the stresses in the compact more uniformly in three dimensions and minimizes cracking. These specimens are then compressed with platens 0.4 times the width of the square compacts in the tensile testing apparatus. (Fig. 3). Occasionally nylon platens and side supports are used to reduce the tendency to fail in shear rather than tension. The force necessary to cause tensile failure (tensile forces are a maximum... 

A method of measuring tensile strength has been developed by Ashton et a/.(13) who also used a cylindrical cell split diametrically. One half of the cell is fixed and the other, which is movable, is connected to a spring, the other end of which is driven at a slow constant speed. A slowly increasing force is thus exerted on the powder compact and the point at which failure occurs determines the tensile strength this has been shown to depend on the degree of compaction of the powder. 

The tensile strength can be measured in two ways (1) direct tensile strength from dumbbell specimens (2) splitting tensile strength from cylinders. Alternatively... 

A special split tensile specimen mold was made to measure tensile properties of propellant during cure. A miniature casting is made in a dumbbell-shaped mold. The gage section of the mold is split axially so that it can be removed to expose the partially cured propellant. The mold is placed in a tensile tester, and the specimen is pulled with the end parts in place. Figure 17 shows that during the early stages of cure... 

PETN, LX-04-1, PBX 9404, PBX 9011 and RX-08-AZ were tested using the Hopkinson split-bar technique. This technique allows data acquisition up to strain rates of ca 5 x 103 in/in/sec. The " dynamic" tensile strength of these expls is ca four times greater than their "static" strength. 

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