抄録
To investigate some fatigue properties of netting twines as shown in Table 1, the present experiments were carried out by giving netting twines with various static loads (W) for about a week.
Various values measured are shown in Table 1.
As it is unsuitable to use initial diametre of twines (D0) in static loads being equal to zero, they are decided reasonably (Fig. 1).
In order to examine shrinkage and elongation of twines, D/D0, (1-D/D0)/W/D2 and ε/30/W/D2 are calculated by making use of the diameter above mentioned when values of W/D2 are ?? large and small (Fig. 1 and Table 3. ε is elongation by static loads).
From Table 3, order of easily deformation is as following, cremona, polyethylene, polypro-pylene. amilan and tetoron.
When values of W/T(W-0) are equal to or below 0.4, values of T/T(W=0) are equal to one and if values of W/T(W=0) go over 0.4, values of T/T(W=0) decrease rapidly (Fig. 3). (T shows breaking strength).
Elongation of polyethylene, polypropylene and cremona netting twines are uneasy to reco-ver compared with amilan and tetoron (Fig. 4 and Table 5).
