Resurgence of Aluminium in Structural Engineering

Resurgence of Aluminium in Structural Engineering

S. K. Ghaswala, Consulting Engineer, Mumbai
More than half a century ago this author presented a paper on "Basic Concepts of Structural Theory of Aluminium Alloys" at the 4th Congress of IABSE (International Assoc. of Bridge and Structural Engineering) at London and Cambridge in August/September 1952. This was followed by another paper on "Some Aspects of the Plastic Design of Aluminium Structures," published in Vol 16 of IABSE Congress at Zurich, Switzerland in 1956. These two papers together sought to unify the basic principles for design of aluminium structures and tended to establish this light metal as a distinctive structural material as was known half a century ago. Since then progress was rather limited except for its use in 'aircraft structures and to some extent in the framework of railway coaches.

Currently, there has been a resurgence of this metal due to a deeper understanding of its design theory as well as the availability of a larger variety of alloys with enhanced strength. A synoptic review of these aspects is presented here by first evaluating the basic differences in steel and aluminum and then briefly highlighting the importance of buckling, torsion and plasticity, in order to stress the need for designing aluminum differently from steel and not merely copying it. This is followed by the applicapability or otherwise of aluminum in different types of bridges; jointing techniques and some interesting and unique applications of aluminium indicating the versatility of this metal. The article ends with a digress on futuristic trends on how aluminium will shape up and show its radiating potencies in the years to come in the domain of structural engineering in construction industry.

Differing Properties

Resurgence of Aluminium in Structural Engineering
The Structural design of aluminium is distinctly different from that of steel mainly because of its differing physical and mechanical properties.

The density of aluminium at 2.7, its elastic modulus at 70,000 N/mm2 and its rigidity modulus at 27,000 N/mm2 are all one-third of steel, while its Poisson's Ratio at 0.33 is nearly the same as steel. Unlike steel aluminium has a non-linear steress/strain curve. The linear thermal expansion of aluminium at 23 x 10-6 /C is nearly twice as large as steel.

Aluminium melts at 600°C as against steel at 1500°C, requiring careful consideration during welding.

Aluminium has a thermal conductivity nearly three times, and electrical conductivity about twice that of steel.

Aluminium resists the ravages of time, temperature, rust, humidity and warping adding to its long life-cycle.

In comparison with steel the cost of machining and shaping aluminum is just l/9th of steel and canthis form a deciding factor in its selection.

Aluminum, unlike steel, is available in a variety of strengths tempers, mechanical properties as a well as shapes, such as extrusions like bulb angles and channels, top-hat sections and squat and I sections.

NBMCW September 2009

Click Here
To Know More / Contact The Manufacturer
Please provide your details we will contact you as soon as possible
Please let us know your name.
Invalid Input
Please let us know your Designation.
Invalid Input
Please let us know your City.
Please let us know your State.
Please let us know your Country.
Please let us know your Contact Number.
Please let us know your email address.
Please brief your query.

Innovation in Bridges Components and Materials

The Infrastructure Industry is continuously evolving; new roads, elevated corridors, expressways, railways, dedicated corridors, metros, mono-rails are being constructed all the time. They also require constant Read More ...

World's Most Amazing Bridges

The 6.5 feet wide walkway in the Hongyagu Scenic Area in Hebei province hangs 755 feet above the ground, and is the world's longest bridge, which opened in 2017-end. Designed by Tel Aviv architect Haim Dotan Read More ...

An Experimental Study to Estimate Loss of Prestress and Determining Fundamental Natural Frequecny of Prestressed Concrete Bridge

Prestressed Concrete (PSC) structures especially bridges are being largely used all over the world due to their multifarious advantages in terms of structural behaviour, economy as well as aesthetical Read More ...

Experimental Investigations on the Structural Behaviour of a Distressed Bridge

Four Span Pipe Bridge
Distressed structures require necessary remedial measures in order to restore their original structural properties like strength and stiffness. Validating the effectiveness of the proposed qualitative remedial Read More ...

World’s Aesthetic Foot Bridges

Foot Bridges
Footbridges have a longer history than road or railway bridges. Ancient footbridges comprised of natural materials such as roots of trees, ropes, stones, masonry, and wood. Modern footbridges are built Read More ...

Load Testing of Second Thane Creek Bridge, Mumbai

Thane Creek Bridge
Load testing is done to determine the safe load carrying capacity of structures, determining if specific legal or overweight vehicles can safely cross the structure or needs to be restricted and the level of post Read More ...

Corrosion Preventive Methods Adopted for Concrete Bridges During Construction

Bridge in Central Kerala
Cement concrete is a versatile building material and is the second most consumed material in the world, after water. It is made using porland cement, coarse, and fine aggregates, water and one or more Read More ...

Recent Developments in Design and Construction of Concrete Road Bridges

Concrete Road Bridges
Planning, design and construction of bridges and flyovers is very challenging at places with space constraints. There has been rapid development with the availability of high strength steel and concrete Read More ...

Integral Abutment Bridges

Integral Abutment Bridges
The conventional bridges use expansion joints and bearings to accommodate the thermal movements of the bridge. However, they don't completely eliminate the distress caused because Read More ...

Restoration of 45 Years Old PSC Bridge by External Post Tensioning

Bridge Restoration
The use and advantages of Post Tensioning are very well known in the Civil Engg Industry as it has been in use for the last 40 to 50 years. Post tensioning is one of the best methods to induce stresses in the concrete Read More ...

Signature Bridge: A Landmark Engineering Marvel in the Making

Signature Bridge
Wazirabad Bridge or Signature Bridge Project is an initiative of Delhi Government, planned during the Commonwealth Games. It was conceptualized to be a landmark tourist icon that would also speed Read More ...

Analysis of Integral Abutment Bridge by Grillage Method

Integral Abutment Bridge
An integral bridge may be defined as having no expansion joints or sliding bearings, the deck is continuous across the length of the bridge. Integral bridges are alternatively referred to as integral abutment Read More ...

Soil Structure Interaction of Integral Bridge Using Finite Element Method

Soil Structure Interaction
A type of bridge that is used extensively in road applications in particular is the integral abutment bridge (IAB). The concept of "integral abutment bridge" has recently become a topic of remarkable Read More ...

Rehabilitation of Distressed Bridges

Cracks in Ravi Bridge
Before carrying out any testing of the concrete structures using NDT methods, visual inspection of the structure is a must. Visual inspection is not confined to the surface, it also include examination of bearings Read More ...

Strengthening of Mithi River Bridge at Mumbai Airport

Mithi River Bridge
Strengthening of RCC structural elements is a common task for maintenance nowadays. For the purpose of strengthening, several materials and methods are available such as sprayed concrete Read More ...

Bridge Health Management

Bridge Health Management
Bridge maintenance is necessary to keep all bridges traffic worthy. Immediately on completion of a bridge there is a need to keep observation on its behaviour under various conditions Distress if any Read More ...

New Building Material & Construction World

New Building Material & Construction World
MGS Architecture

Modern Green Structures & Architecture

Modern Green Structures & Architecture

Lifting & Specialized Transport

Lifting & Specialized Transport

Indian Infrastructure & Tenders Week

Indian Infrastructure & Tenders Week