Page 1 of 18 DOES AFS LOGIC WALL COMPLY WITH AS3600-2009 – CONCRETE STRUCTURES CODES ?
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Page 1 of 18
DOES AFS LOGIC WALL
COMPLY WITH
AS3600-2009 – CONCRETE
STRUCTURES CODES ?
Page 2 of 18
AFS LOGIC WALL RELIES ON THE UNISEARCH REPORT (refer Appendix) FOR AS3600 COMPLIANCE Engineers, architects and certifiers should read the following to decide if AFS LOGIC WALL can satisfy the following requirements of UNISEARCH. 1. AFS Logic Wall must be protected and maintained adequately
The requirement of Unisearch is shown in the adjacent diagram. The membrane shown must be used and maintained. Questions to ask are: (i) What is the life of the membrane system? 10 years or
20 years? AS3600-2009 requires a structural life of 50 years +/- 20% = 60 years.
(ii) Who will provide 60 years warranty for a membrane
system? (iii) If the life of the membrane system is, say 20 years, the
membrane paint must be repeated at least 3 times to satisfy the 60 years structural life. Who will do this maintenance during the life of the structure since Australia has no law to enforce the maintenance of a membrane system on a building wall?
2. Metal channels should not corrode
Lightly galvanised sheets for the manufacturing of metal channels are bent to form, cut, punched, and screwed on site. Hence, galvanising of the AFS metal channels are significantly compromised. This condition of the metal channels therefore does not satisfy Unisearch’s requirement, i.e. metals with compromised galvanising must have concrete cover or membrane protection. For further information and photos refer to (download) AS3600 Durability Compliance Assessment of AFS Logic Wall.
3. Unisearch states that if Items 1 and 2 are satisfied, AFS Logic Wall can be said to comply with the “deemed to satisfy” condition of the BCA.
It appears that the writer of the Unisearch Report is not aware or ignores the AS3600-2009 Commentary shown in the Appendix (refer highlighted paragraphs). The AS3600-2009 Commentary clearly states that systems that rely on coating systems (such as membrane systems of the AFS Logic Wall) are outside the scope of AS3600-2009. In fact, the statement “AFS Wall must be protected and maintained adequately” contradicts AS3600 since AS3600 is not written for solutions based on protective systems. AS3600 only relies on the concrete cover and nothing else. Therefore, AFS Logic Wall cannot be said to comply with the “deemed to satisfy” condition of the BCA which is AS3600-2009.
Page 3 of 18
BASED ON THE ABOVE, QUESTIONS TO THE: Builder/Developer
Check if your building is insurable if the structure does not comply with AS3600 and displaying corrosion and mould/mildew?
Engineer/Architect/Certifier
For further explanation Engineers can refer to (download) AFS Logic Wall Structural Engineering Assessment. Can the engineer override the AS3600 Commentary and the photos shown in the Appendix? Is the specifier prepared to accept the responsibility for any consequences as a result of ignoring AS3600-2009 Commentary?
Installer
Formworks consisting of fibre cement sheets are similar to besser blocks which are required to be wetted first and then 230mm concrete slump is used. Otherwise as shown in Photo No: 1 of the Appendix air voids are not avoidable. What would be your answer if you are accused that the air voids are an installation problem – not a product problem due to the use of fibre cement sheets as formwork?
The above issue is relevant to both internal and façade walls as AS3600 requires maintenance free system by the provision of concrete cover, not membrane protection, for both cases. AS3600 is clear that membrane system protection is not allowed. It is recommended that the following statements should be obtained from the engineer/installer to protect the Certifier/Builder/Developer: Structural Engineer: “I acknowledge that AFS Logic Wall requires to be protected by a water/air proof membrane system to be maintained for a minimum of 60 years structural life. I further acknowledge that the AS3600 – 2009 commentary states that protection by a membrane system is outside the scope of AS3600”. Installer: “I acknowledge that fibre cement sheets, like besser blocks, are porous in nature hence require wetting the forms prior to concreting and using high slump concrete to avoid the occurrence of air voids. I therefore confirm that AFS Logic Wall having fibre cement sheets concrete filled by us shall not have air voids in them”.
Page 4 of 18
APPENDIX
1. UNISEARCH REPORT
2. AS3600-2009 COMMENTARY
3. PHOTOS
4. INDUSTRY NEWS FOR PUBLIC AWARENESS
Page 5 of 18
Page 6 of 18
Page 7 of 18
Page 8 of 18
Page 9 of 18
Page 10 of 18
Page 11 of 18
Page 12 of 18
Page 13 of 18
Page 14 of 18
Page 15 of 18
PHOTO NO: 4
PHOTOS FROM CANBERRA – INDICATING THAT THE PROBLEM DOES NOT ONLY OCCUR IN CLOSE PROXIMITY TO WATERFRONT PROPERTIES
Page 16 of 18
PHOTO NO: 4 (cont’d)
Page 17 of 18
Page 18 of 18
Related Documents
