NZ Construction News (Feb / Mar 13) CCANZ Updates Technical Concrete Publications

27 Feb 2013

The Cement & Concrete Association of New Zealand (CCANZ) has recently enhanced its suite of technical publications by updating and developing several Information Bulletins (IB) and Technical Reports (TR).

IB 80 Residential Driveways and Paths is a new publication designed to assist with achieving a finish product that satisfies the functional and aesthetic demands of home owners.

IB 55 Concrete for the Farm, TR 03 Alkali Silica Reaction and TR 14 Best Practice Guide for the Use of Recycled Aggregates and Materials in New Concrete are existing publications that have undergone revision to ensure they reflect best practice and incorporate current Standards.

CCANZ CEO, Rob Gaimster, highlights that the provision of technical information, designed to enable users of cement, concrete and concrete products to achieve optimum results, is a key objective of the Association.

“CCANZ remains firmly committed to delivering industry solutions based on technical expertise, as well as well as co-ordinating concrete-based education, training and research initiatives,” says Mr Gaimster. “An important component of this is supplying relevant and up-to-date information that covers best practice, laboratory and on-site research, as well as general guidance.”

Residential Concrete Driveways and Paths (IB 80) – The basic function of residential driveways, paths and patios is to provide safe, easy access onto or around a property.  Concrete is typically used to provide a durable paving surface sloped to enable surface water run-off, but one which can incorporate a wide range of decorative finishes to complement the design and landscaping of the residence. 

While providing a residential pavement is relatively straightforward, there are many design and construction aspects that need to be considered to produce a finished product that will satisfy both the functional and aesthetic requirements demanded by home owners.  This IB provides guidance on the planning, design, construction, maintenance and specification aspects that need to be considered to ensure a successful concrete paving project.

Concrete on the Farm (IB 55) - On the farm, concrete is often used in relatively small and simple structures so it is easy to think that its performance is not as critical as in more complex structures.  Nevertheless, concrete structures such as milking shed floors represent a large investment, and their replacement or repair can involve considerable time, inconvenience and expense.  In addition, some structures on the farm are exposed to conditions that may rapidly damage concrete of inadequate quality.

This IB explains how to design, mix and place concrete so that concrete structures on the farm will last as long as intended. It concentrates on concrete that is cast in-situ, rather than masonry, precast concrete products, roading materials or cement stabilised soil.

Alkali Silica Reaction (TR 03) - Originally written in 1991 and fully revised in 2003, this TR provides a comprehensive review of New Zealand and international experience and research to enable concrete specifiers and suppliers to minimise the risk of damage caused by alkali silica reaction (ASR) in New Zealand concrete.  It applies to concrete to be used in new construction, not to the repair or control of damage in existing structures, and to concrete containing potentially reactive aggregates or aggregates of unknown reactivity. 

The 2012 amended version incorporates recommendations on ASR observed in some precast concrete piles using South Island aggregates containing microcrystalline quartz or strained quartz.  Precautions to minimise the risk of ASR in concrete containing recycled concrete aggregate are also covered.

Best Practice Guide for the Use of Recycled Aggregates and Materials in New Concrete (TR 14) - This TR outlines the processes involved in the use of recycled materials as aggregate in concrete and the effects of these materials on the fresh and hardened properties of concrete made from them.  Based on overseas and in New Zealand experience, it is intended to act as a resource on the practical performance and engineering properties of recycled materials as aggregate in concrete supplied in accordance with NZS 3104:2003.

The TR also raises awareness of the need for concrete recycling and presents the technical guidelines on the use of recycled aggregate in concrete, and on the recovery of concrete aggregate and fines from leftover fresh concrete.  It may also be of interest to regulatory bodies for determining the suitability of recycled material for use in building and civil engineering projects.