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| PDF : |  09060203.pdf |
| title(En) : | Puncture Test in Plywood and Hardboard. II. |
| author(En) : | Shitomo Mamada |
| information : | Mokuzai Gakkaishi 9(6), 203-207 (1963) |
| assort : | Original Article |
| summary(En) : | To obtain the breaking load, deflection and absorbed energy in puncture test, plywood and hardboards were supported in circular plate of 20cm diameter. A striking block, the weight of which was 1kg and the radius of point circle was 2.5cm, was equipped with an accelerometer as illustrated in Fig. 1, and the relations of acceleration g (load)-time t(deflection) were taken out by oscilographs (Fig. 3) in Braun tube. Fig. 2 shows experimental opparatus to obtain oscilographs. Static tests by the similar system were also carried out to obtain static load and deflection. The physical properties of test boards are shown in Table. 1. As for the three formulae 4,6 and 7 to calculate the puncture deflection, formula 6 was considered to be most applicable. The values of deflection obtained from respective formula are shown in Table2. The test boards were supported in three conditions, they were : "simply supported", "loosely clamped" in which boards were clamped by hand, and clamped in which boards were fixed as tightly as possible by pincers. Examples of obtained oscilograph are illustrated in Fig. 3, in which the first maximum points of curves show the breaking point of test boards. Table 3 shows examples of g and t obtained at the breaking. The relations between impact and static test are shown in Table 4. The breaking load and deflection, and absorbed energy to break are shown in Table 5. |