Dootson, M.
Description:
1. General Progress
The six months from April to September 1969 have been spent mainly
in consolidating the work of the previous eighteen months.
Firstly, due to major servicing problems, it became necessary to
redesign the resin impregnating head of the filament winding machine.
By the removal of all moving parts from the vicinity. of the resin, these
servicing problems have been completely overcome. Using the redesigned
machine many sheets of high quality glass reinforced epoxy resin have
been produced.
A sophisticated version of the spring mounted lateral extensometer
described in Progress Report No. 3 has been designed and tested. Six
of these have now been produced and are now in service yielding satisfactory
results.
The majority of the period has been spent in setting up the tensile
creep testing machines. This has been necessitated by the discovery that
errors of up to 10% in creep compliance have been obtained through misalignments
of the loading linkages of the order of .01 inch.
All the apparatus is now functioning correctly and more creep results
for uni- and bi-directionally reinforced specimens are being obtained.
Included in these current creep results are not only values for creep
compliances but also for the creep contraction of these specimens.