| Summary: | 碩士 === 國立屏東科技大學 === 木材科學與設計系所 === 95 === The purpose of this study was to improve conventional bamboo scaffolds by using simple door type scaffold design with Moso bamboo and Makino bamboo. The study investigated the development of three bamboo scaffolds manufacture technigues, and analyzed the related strength properties. Furthermore, the study also propoed the specification standard and quality of CAS bamboo scaffolds in general use, regulations on mark, as well as the accreditation standard of bamboo scaffolds in general. Consequently, this can be the reference of products development for the manufacture and basis of accreditation process for further system safty consideration.
As for the load capacity of bamboo scaffold post, three-way mechanical Moso bamboo scaffolds post showed 5418 kgf and was about 2~4 times of two-way mechanical Moso and Makino bamboo scaffolds while the performance of two-way mechanical Moso bamboo scaffolds post is 71 % higher than that of two-way mechanical Makino bamboo scaffolds. Thecompressive failure of two-way mechanical Moso and Makino bamboo scaffolds post both occurred at the joints. The two-way mechanical Moso bamboo scaffolds post also failed due to the shearing and splitting at bolt joint.
In the flexural test for bamboo scaffold post, the transoms composed of solid wood and plywood, especially for SPF had higher load capacity, and was 2 times higher than that of bamboo transoms. Besides, the bending load capacity of A-B condition was 19 % higher than that of conventional bamboo scaffolds tied with steel wires. All the three-way mechanical Moso bamboo scaffolds failed in shearing at bamboo culm. There was 50 % of two-way mechanical Moso bamboo scaffolds failed in lateral pull-out of nail, and 25 % in simple tension and shearing fracture. Both shearing and splitting failure occurred on all the two-way mechanical Makino bamboo scaffolds with Japanese ceder trasom, and 40 % in splintering tension fracture for plywood trasom, and 60 % in splitting failure at bolt joint.
The bracing of bamboo scaffolds with lateral supports increased 4 times of load capacity as compared to that without lateral supports. B-ACQ had 2 times of load capacity higher than that of B-NON. The ACQ treated bracings made no difference in strength property from untreated bamboo bracings, and while the installment of lateral support and reinforcement of the bamboo scaffolds post connections would be the key to improve structural performance.
Comparing to the bending properties among five types of scaffolding panels, the load capacity of type A-SP-18-JC is the highest. As for bending stiffness, type B-SP-18-B had the better performance than type A-SP-18-P. The failure of type A-SP-18-P occurred on the double-layer water-proof plywood reinforcement. Both 40~80 % of types A-SP-18-JC and C-SP-15-JC failed in simple tension fracture, and 20~40 % of them failed in cross grained tensom fracture while 20 % of type C-SP-15-JC failed in shearing fracture.
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