Latest Publications

Description Category Date Author
Loads on Newly-Finished Composite Floors

This article is written in response to frequently asked questions regarding the performance of composite floors soon after concreting. This Steel Advisor article clarifies the basis for some of the requirements given in national and interna...

ERC1005.pdf
Erection & Construction 20/07/2011 Stephen Hicks
Sleeved Holding Down Bolts

One of the greatest problems faced by a steel erector on site is inaccuracy in the locations of the anchor bolts. Precision surveying equipment and techniques are required to accurately set out solidly cast-in anchor bolts in accordance wit...

ERC1004.pdf
Erection & Construction 29/06/2009 Kevin Cowie
Extending High Tensile Anchor Rods with Couplers

There are instances where high tensile anchor rods have been cast in with insufficient projection above the concrete. Extending the anchor rods by welding is generally not permitted. One method to extend the anchor rod is by the use of a th...

ERC1003.pdf
Erection & Construction 27/04/2009 Kevin Cowie
Pre-Tensioning of High Strength Holding Down Rods

Holding down bolts are typically threaded rods of varying lengths. Tightening of the hold down bolts to achieve a minimum level of bolt pre-tension eliminates a potential source of undesirable connection flexibility. Such as in column base ...

ERC1002.pdf
Erection & Construction 02/05/2008 Kevin Cowie
High Strength Structural Bolting

High strength structural bolting offers significant benefits to erection of structural steelwork. It is relatively quick and can be executed on site in all sorts of conditions. However to achieve reliable structural performance the quality ...

ERC1001.pdf
Erection & Construction 01/05/2008 Clark Hyland
Email me when new posts are made to this blog

Loads on Newly-Finished Composite Floors

Written by Stephen Hicks on July 20th, 2011.      0 comments

This article is written in response to frequently asked questions regarding the performance of composite floors soon after concreting. This Steel Advisor article clarifies the basis for some of the requirements given in national and international good practice guides, and provides supplementary information to assist designers when considering this important load case.
Topics: Coating Erection & Construction
 

Sleeved Holding Down Bolts

Written by Kevin Cowie on June 29th, 2009.      0 comments

One of the greatest problems faced by a steel erector on site is inaccuracy in the locations of the anchor bolts. Precision surveying equipment and techniques are required to accurately set out solidly cast-in anchor bolts in accordance with NZS 3404.1. The required setting out tolerances of these fixed holding down bolts is very tight. To provide increased tolerance and some allowance for site adjustment, sleeved anchor bolts can be used. See Figure 1. These allow some adjustment of bolt positioning after concreting. This article describes the requirements for holding down bolts sleeves.
Topics: Coating Erection & Construction
 

Extending High Tensile Anchor Rods with Couplers

Written by Kevin Cowie on April 27th, 2009.      0 comments

There are instances where high tensile anchor rods have been cast in with insufficient projection above the concrete. Extending the anchor rods by welding is generally not permitted. One method to extend the anchor rod is by the use of a threaded coupler. Checks are required to ensure that stripping of the threads and also tensile fracture of the coupler does not occur prior to the tensile fracture of the connected threaded rods. This article presents a method for these checks.
Topics: Coating Erection & Construction
 

Pre-Tensioning of High Strength Holding Down Rods

Written by Kevin Cowie on May 2nd, 2008.      0 comments

Holding down bolts are typically threaded rods of varying lengths. Tightening of the hold down bolts to achieve a minimum level of bolt pre-tension eliminates a potential source of undesirable connection flexibility. Such as in column base plate connections in a seismic-resisting system where the frame stiffness will change if the base plate lifts off the footing, as the rigidity of this connection has a significant effect on the behaviour of the seismic-resisting system(s) and the overall building. One option for achieving the necessary pre-tensioning would be to use direct tensioning equipment but this is difficult to calibrate reliability for structural bolts if galvanised. However, a simpler option is to use the part turn concept of NZS 3404. A bolt extension associated with achieving the minimum bolt proof load applied as a specified turn of nut past snug tight. The method modifies the method previously presented in HERA Design & Construction Bulletin No 56. Included in the end of this article is a worked example for determining the calculation of required amount of nut rotation from snug tight. This article provides additional information to ERC1001 High Strength Bolting.
Topics: Coating Erection & Construction
 

High Strength Structural Bolting

Written by Clark Hyland on May 1st, 2008.      0 comments

High strength structural bolting offers significant benefits to erection of structural steelwork. It is relatively quick and can be executed on site in all sorts of conditions. However to achieve reliable structural performance the quality of the bolt assemblies and the installation procedures need to be appropriately controlled. This article summarises the key aspects of high strength structural bolting that need to be understood by those specifying, purchasing and installing these bolts.
Topics: Coating Erection & Construction
 
   
ABOUT SCNZ