The Structural Engineer's Corner

Eng. Onorio Francesco Salvatore

Traffic loads on road bridges: division of the carriageway into notional lanes according to Australian Standard 5100.2


The load models defined in the Australian Standard 5100.2 shall be assumed to occupy one standard design lane of 3.2 m width. The number of standard design lanes is defined as: n = b / 3.2 (rounded down to next integer) where: – n = number of standard design loads; – b = width between […]

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Design for durability, part II – surface of members in interior environments


Following the previous post on durability (“Design for durability, part I – surface of members in contact with the ground“), in the following there are the requirements for surface of members in interior environments.

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Design for durability, part I – surface of members in contact with the ground


Similarly to European Codes, the Australian Standards specify the durability requirements according to the exposure classifications. In the following, the requirements for the surface of members in contact with the ground. Members protected by a damp-proof membrane; Exposure classification = A1; Minimum concrete strength, f’c = 20 MPa; Minimum initial curing = continuously for at least […]

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Class of concrete in Australia according to AS 3600 and AS 1379


In Australia, two different types of concrete are specified and are: – Normal-class; – Special-class. The Normal-class should have some attributes as defined in the AS 1379 and specified through some basic parameters. The parameters are: – standard strength grade; – slump at the point of acceptance; – maximum nominal size of aggregate; – method […]

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Strength of soils at Serviceability and Ultimate Limit States


In a previous post we discussed about the relations to use in order to evaluate the embedment depth of the utility services poles direct-planted. To whom could have missed it, the post is the following: Embedment depth for utility services poles according to Australian Standard 4676 The relation discussed requires values for the foundation soil. […]

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Embedment depth for utility services poles according to Australian Standard 4676


When dealing with methods for proportioning footings and poles, an useful reference is the Australian Standard 4676, titled “Structural design requirements for utility services poles”. For direct-planted poles, hence not on square pads, the Engineer can make some reasonable assumptions on the location of the centre of rotation of the footing and the vertical distribution […]

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Coefficient of exposure for wind action – Difference between ISO 4354 and AS/NZS 1170.2


The Australian Standards adopt in many parts recognized International Standards. For what regards the Wind Action the reference is the ISO 4354 “Wind action on structures”. One of the differences between the AS/NZS 1170.2 and the ISO 4354 is the exposure factor Cexp. The Australian Standard decided to not adopt that factor because it has […]

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Ultimate Limit States and Serviceability Limit States in Australian Standard AS 1170


The Limit States used in Australia (AS 1170.0 – Structural design actions) are similar to those of other codes, like the ISO ones. There are: – Ultimate Limit States, ULS; – Serviceability Limit States, SLS. There are two different types of Serviceability Limit States: – SLS1 => the structure and the non-structural components do not […]

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Methods of Structural Analysis according to AS 4100 – Part 3: Braced frame vs Sway frame in the moment amplification method for elastic analysis


In the previous post, we discussed about the Elastic analysis at first-order with moment amplification. We have seen how this method can be a good alternative to a second-order analysis. Basically, we need to increase the moment by a certain quantity including in this way the second-order effects. We have also introduced the moment amplification […]

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Excel spreadsheet for the evaluation of the Dynamic Response Factor as per AS 1170.2


As announced in a previous post (The Dynamic Response Factor as per Australian Standard 1170.2), I’m putting on free download an Excel tool I just created for the evaluation of the Dynamic Response Factor as per Section 6 of the Australian Standard 1170.2. The inputs needed are the following: Design wind speed for chosen direction; […]

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