To obtain a multiple nonmetallic optical fiber cable which has necessary tensile strength, allows handling in a manhole as well and is bendable by incorporating polyparaphenylene benzo-bis-oxazole fibers into a tension member existing at the center of a spacer.
Coated optical fiber ribbons 1 are housed into the grooves of the grooved spacer 2. The tension member 3 existing at the center of the spacer 2 comprises a round rod of the fiber reinforced plastic(FRP) of the polyparaphenylene benzo-bis-oxiazole fibers. The outside diameter of the round rod is 5.1mm when the elongation strain executed on the optical fibers is 0.2% while the laying tension thereof is, for example, 7940N. The polyparaphenylene benzo-bis-oxazole fibers have the modulus of elasticity in tension of about 2.6 times that of aramid fibers. The necessary tensile strength is obtd. even if the tensions member smaller than in the case the aramid fibers are used by using such fibers for the central tension member.
IWATA HIDEYUKI
TOMITA SHIGERU
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