Shatter resistance tests

A large amount of carpet waste is disposed of in landfills each year. This not only poses economical and environmental problems to the industry, it also represents a severe waste of resources because the waste material can prove to be valuable for construction applications. This study focused on the use of carpet waste fibers in fiber reinforced concrete and demonstrated that such reinforcement can effectively improve the shatter resistance, toughness, and ductility of concrete. Performance enhancement has also been observed in the drying shrinkage test. Such improvements in concrete performance is especially beneficial for concrete structures in seismic zones as the increased toughness could improve the reliability and shock resistance of the structures. 

With harder materials like aggregates, sands and fillers, an impact test machine is used59 which uses a 14 kg hammer to drop from a height of 380 mm onto a specified quantity of the sample in a cup. The amount of fines produced by the impact is an indication of the shatter resistance. 

Because seed of the Brassica napus species was distributed widely at the outset of production, it dominated the acreage for a few years. Yield tests showed that Brassica napus outyielded Brassica campestris. However, earlier maturity and more shattering resistance of Brassica campestris were more agronomically desirable features particularly in the northern areas of production, and Brassica campestris soon occupied more acres than Brassica napus species. 

The compressive test was condncted on 76 mm (diameter) by 152 mm (height) cylinders according to ASTM C39-86 at an age of 28 days. As seen from Table 14.1, the compressive strengths varied from mix to mix, most likely due to normal variation. However, it appears that the compressive strength for Mix 8 with 1.4 vol% waste fibers was lower due to the fiber addition. In all the tests, good shatter resistance was observed because of the fiber reinforcement, especially in those with relatively high fiber dosage rates (Mixes 5-8). 

Studies have shown that polycarbonate plastic lenses are significantly more shatter-resistant than other types. Glass and plastic lenses that were tested met federal standards for shatter resistance, but only polycarbonate did not break when struck with the kind of force generated during common incidents and injuries. Research showed that shattered lenses were possibly to blame for many eye injuries. 

The drop shatter test indicates the resistance of a coal or coke to breakage on impact (see D440). A sample is dropped in a standard way a number of times from a specified height. Eor the tumbler test or abrasion index (ASTM D441), the coal or coke is rotated in a dmm to determine the resistance to breakage by abrasion (18). 

We test the impact resistance of polymer plaques using the configuration shown in Fig. 8.8. We subject circular injection molded plaques to the shock of a falling weight with a hemispherical impacter. This test is also known as the Dart Drop Test . Samples can fail in a brittle or a ductile manner. Brittle samples often shatter. Ductile samples can split or a small disk may be punched out of their center. This test provides results that are analogous to those obtained from un-notched impact beam testing. 

The glass mat at the core of the STX sheet was shown to impart some very unusual impact properties to the material. The testing performed in the laboratory (Gardner drop test) and the field results from production components have shown that, in contrast to glass reinforced plastics, the failure mode is elastic rather than brittle. The resultant damage is a hole with little or no crack propagation around the impact area whereas the other reinforced materials will shatter under similar conditions. The STX failure mode applies not only at room temperature, but is equally valid at -40°F. STX impact resistance increases with the thickness of the material, i.e., V4 in. thick plate will resist much higher impact loads than Vs in. thick plate. 

---