Summary: | Bibliography: leaves 69-71. === The aim of the testing was to compare the relative positives and negatives of the Butterfly Tie and the Crimped lie as regards to water transfer, tensile and compression strengths based on the Australian Code [AS 2699-l 984] requirements as it is more comprehensive. The reason was because the Butterfly Tie has been promoted in cavity wall construction in South Africa for a number of reasons, for example: * NHBRC (National Home Builders Registration Council) compels contractors to use the Butterfly Tie * SABS 28:l986 and SABS O 164-1 :1980 also compel the use of Butterfly Tie, even though there is an anomalous statement in the specifications. Another reason was because the use of the Crimped Tie was not being promoted in cavity wall construction in South Africa mainly because of a lack of information regarding characteristic strength and its resistance to water transfers. The following tests, based on the Australian Code, which is more stringent than the South African Codes were then carried out on the Butterfly Tie and the Crimped Tie: * Tests for water transfer * Tests tor compression and tensile strengths using couplets * Tests for compression and tensile strengths using ties only. Although the testing showed that the Butterfly Tie and the Crimped Tie fulfilled the requirements of the Australian Code, there were negative aspects relating to the Butterfly Tie. It is recommended that serious considerations be given by the South African Bureau of Standards to include the Crimped Tie in its Code of Practice for Cavity Walls.
|