Study on Structure and Intensity of Japanese Trellis

Abstract

In order to analyze Japanese trellis statically, a model of the trellis was made and experimented.
Some conclusions are as follows.
1) Center wires, side poles and their bracing wires are influenced by the loads more than edge wires, corner poles and their bracing wires.
2) Not only compression but bending moment is loaded poles and the smaller the angle between pole and bracing wire, bending moment becomes greater. When the poles made of reinforced concrete are selected for Japanese trellis, the bending moment has to be calculated sufficiently.
3) Close agreement between experimental and theoretical values was obtained except side poles and their bracing wires. The experimental proportions of each wire's tention and netting wire's tention of the model and the practical proportions of the actual trellis resembled each other. So experiment of using the model is available for static analysis of Japanese trellis.
4) The effect of initial tention on the tention at weight hanging is very small, so that initial tention of center wire is enough to strain to such degree as the wire sag little.
5) Considering effective utilization of orchard and favorable condition of trellis intensity, the optimum angles of bracing wire, side pole inclination and corner pole inclination are about 60°, 60° and 45°, respectively.