A number of the pleasure craft built in F/C, of which published accounts were
available, used a single layer of 6 mm (1/4") steel rod placed longitudinally at
50-75 mm (2"-3?) spacing. This was felt to be unsuitable for two reasons. Firstly,
a rapid calculation showed that unless, an excessive number of layers of heavy gauge
mesh were used in conjuction with this rod there would be insufficient steel in the
mortar to achieve the required 480 kg,/m3 lb/ft3) of reinforcement. Secondly, if
only longitudinal rode were Used then the mortar and wire mesh would be required to
resist the vertical stresses caused by the motion of the vessel in waves. Concrete
or mortar alone being weak in tension and the proposed number of layers of mesh not
having sufficient strength in themselves to resist initial distortion, it was falt
that such a disposition of rods was inadequate to prevent the risk of cracking with
consequent corrosion problems. Consequently, a framework of longitudinal rode at
75 mm (3") centres joined by vertical rods at 100 mm (4") °entree was chosen as 'UK)
basic rod structure.
A number of the pleasure craft built in F/C, of which published accounts wereavailable, used a single layer of 6 mm (1/4") steel rod placed longitudinally at50-75 mm (2"-3?) spacing. This was felt to be unsuitable for two reasons. Firstly,a rapid calculation showed that unless, an excessive number of layers of heavy gaugemesh were used in conjuction with this rod there would be insufficient steel in themortar to achieve the required 480 kg,/m3 lb/ft3) of reinforcement. Secondly, ifonly longitudinal rode were Used then the mortar and wire mesh would be required toresist the vertical stresses caused by the motion of the vessel in waves. Concreteor mortar alone being weak in tension and the proposed number of layers of mesh nothaving sufficient strength in themselves to resist initial distortion, it was faltthat such a disposition of rods was inadequate to prevent the risk of cracking withconsequent corrosion problems. Consequently, a framework of longitudinal rode at75 mm (3") centres joined by vertical rods at 100 mm (4") °entree was chosen as 'UK)basic rod structure.
การแปล กรุณารอสักครู่..