The Structural Engineer's Corner

Eng. Onorio Francesco Salvatore

[DOWNLOAD] Annual Probability of Exceedance for structures in New Zealand according to AS-NZS 1170


In this post an Excel spreadsheet based on the AS/NZS 1170 is available. Scope of the tool is to define the Annual Probability of Exceedance, P (and, hence, Average Recurrence Level, R), for Ultimate State Limit and Serviceability Limit States. The values are referred to New Zealand, as per Section 3, Table 3.3. The Annual […]

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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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Strength grade of concrete in Australia


The standard strength grade is basically the compressive strength capacity of the concrete. The standard grades in Australia, as per AS 1379 and AS 3600, are the following:

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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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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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Site wind speed according to AS/NZS 1170.2


In order to obtain the Design wind velocity, the Structural Engineer needs to define the Site wind velocity. This value is substantially defined as the Regional wind velocity modified taking into account the direction and the exposure of the site. The formula used is: Md is a wind directional multiplier for the 8 cardinal directions […]

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Regional wind speed according to AS/NZS 1170:2


In order to obtain the design wind speed to be used in the calculation of design wind pressure, a regional wind velocity and a site wind velocity must be calculated. VR, the Regional wind speed, is defined as a 3-second gust wind speed. It is an all-directional basic action because no considerations on direction from which wind gust is […]

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