AS 5100.1:2017 pdf free.Bridge design Part 1: Scope and general principles.
7 ALTERNATIVE DESIGN METHODS AND MATERIALS
This Standard does not preclude the use of techniques or materials other than those specified in the Standard.
Where this Standard does not cover a design requirement or where bridges arc to be constructed from materials other than those covered specifically by this Standard, reference shall be made to other relevant Standards and current technical literature for material-specific performance, durability requirements and good practice. All other parts of the AS(AS/NZS) 5100 series shall apply.
The use of alternative design methods and materials shall be subject to approval of the relevant authority.
NOTE: For information on special studies to justify the use of alternatives. see Appendix B.
8 DESIGN PHILOSOPHY
8.1 General
The design shall consider intended function, aesthetics. constructability, maintainability. sustainability. climate change and safety in design.
The design shall be based on engineering principles, experimental data and experience.
All structures shall be designed and detailed to fail in a ductile manner after they reach the ultimate limit state, so far as is reasonably practicable, such that when any element reaches an ultimate limit state alternative load paths shall ensure the continued stability of the structure. Where it is not practicable to ensure overall stability of the structure, consideration shall be given to segmentation of the structure to limit the consequences of any structural failure.
The material parts of this Standard provide a range of capacity reduction factors that are based on the material properties and the degree of ductility for the mode of failure. Design using any material or mode of failure not explicitly covered by this Standard shall use a capacity reduction factor not greater than a capacity reduction factor given in this Standard for a similar level of ductility.
To ensure the safety and performance of the structure, attention shall be given to the following:
(a) The quality control exercised in fabrication.
(b) Supervision on site.
(c) The control of unavoidable imperfections.
(d) Competencies, qualifications, experience and skill of all personnel involved.
(e) Documentation of design assumptions to ensure control over the conditions of use of the structure during its life.
(f) Application of statistical methods and documentation of construction processes and material properties.
In addition, management control and supervision by professional engineers shall be undertaken at all stages of the design, construction and maintenance to prevent the occurrence of gross errors.
8.2 Design life
The design life of structures covered by this Standard shall be not less than 100 years unless otherwise specified. For the design of ancillary elements such as light poles, sign structures, drainage systems and noise barriers, a shorter design life may be specified by Clause 23.2 or by the relevant authority.
Elements such as bearings and expansion joints typically have a design life of less than 100 years. Provision shall be made to facilitate inspection, maintenance, removal and replacement of such elements and any fixings shall be detailed to be reusable.
8.3 Limit states
8.3.1 General
A structure or structural element shall he considered unfit for use if it reaches any one of a number of states at which it no longer satisfies the criteria governing its performance or use. All appropriate limit states shall be considered in design. Limit states are classified as-
(a) ultimate limit states (ULSs): or
(b) serviceability limit states (SLSs).
Unless specified otherwise—
(1) an ultimate design action is an action that has a 5% probability of being exceeded during the design life, which (for a design life of 100 years) represents an average return interval of 2000 years: and
(ii) a serviceability design action is an action that has a 5% probability of being exceeded per year, which represents an average return interval of 20 years.
Standards Australia www.standards.AS 5100.1 pdf download.