physics

Macalloy

Macalloy is a physics topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Macalloy rather than just read about it. In short: McCalls Special Products Ltd is a British manufacturer of steel bar and cable components for tensioned concrete, ground anchors, curtain walling, and steel structures. It operates under the Macalloy brand and claims to be a world leader in that market.

Key takeaways

Macalloy belongs to physics; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Macalloy to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Macalloy from memory before moving on to harder problems.

Reference excerpt

McCalls Special Products Ltd is a British manufacturer of steel bar and cable components for tensioned concrete, ground anchors, curtain walling, and steel structures. It operates under the Macalloy brand and claims to be a world leader in that market.

Macalloy's work supports landmarks including the Sphere at the Academy Museum of Motion Pictures, VTB Stadium, Stade Roland Garros, Tottenham Hotspur Stadium, Soccer City Stadium, Marina Bay Sands, Jewel Changi Airport, Forth Road Bridge, and Burj Al Arab. As of 2021, 3⁄4 of the company's products are exported.

History

McCall and Company Ltd was founded in 1921 by T H McCall, Edwin Llwewllyn Raworth, and C W Hamilton, on Queens Street, Sheffield to supply steel rebar for concrete contractors. In 1927, it moved to former railway engineering sheds on Nunnery Lane for two years then again to its steel supplier, United Bar Strip Mills' Templeborough Steelworks. In 1948, the firm began to manufacture bars for post tensioned concrete. These were used to reinforce a 500 foot (150 m) central span of the 1960 M2 Medway Bridge, then the world's widest prestressed concrete span. McCall and Company Ltd became a subsidiary of United Steel Companies Ltd in 1962 and three years later moved to Meadowhall Road, Rotherham. In 1966, United Steel Companies Ltd was nationalised as British Steel. Allied Steel and Wire Ltd purchased McCall and Company Ltd in 1975, relocating it to Hawke Street as McCalls Special Products Ltd. Allied Steel and Wire Ltd failed in 2002 and in 2003, a management team led by Peter Hoy purchased the assets of McCalls Special Products Ltd. A new Company was incorporated to continue the McCalls Special Products Ltd name and trade. In 2006, the business moved to the former Dinnington Colliery.

Awards McCalls Special Products Ltd was awarded a Queens Award for Export Achievement in 1996 and in 2010, a Queen's Award for Enterprise: International Trade (Export).

Controversies

Clyde Arc Bridge

Severfield plc subsidiary Watson Steel Structures Ltd fabricated the Clyde Arc Bridge in 2007. It had to be closed in 2008 because a clevis connector failed and a 35 metre long tension bar fell onto the carriageway. Another clevis was found to be cracked and it was decided to replace all 14 tension bars in the structure. Watson Steel Structures Ltd claimed £1.8 million from Macalloy, the clevis supplier, alleging its product was faulty. Macalloy denied the claim and countered Watson Steel Structures Ltd had only specified minimum yield stress for the components.

Delhi footbridge collapse Twenty seven workers were injured, five of them seriously, by the collapse of a footbridge to the Delhi Commonwealth Games Stadium. The 2010 collapse was highlighted by commentators questioning how ready Delhi was to host the Games. Macalloy fabricated components of the 95 metre collapsed structure to a design provided by Tandon Consultants. The Government of Delhi opened an investigation and demanded explanations from Macalloy.

Fatal accident In 2015, McCalls Special Products Ltd pleaded guilty to breaches of Section 2 and 3 of the Health and Safety at Work etc. Act 1974. It was fined £200,000 on each, to a total of £400,000, plus £16,804 in costs. The charges related to a 2013 fatality when the victim's clothes caught in a tape wrapping machine and he was dragged in, suffering crush injuries. Macalloy was criticised for inadequate machine guards and risk assessments.

References

External links Macalloy

Illustrations

Macalloy: Macalloy struts, Changi Airport, 2003 — Macalloy struts, Changi Airport, 2003

Worked examples

Example 1 — a first encounter with Macalloy

Start with the simplest possible case. Write down what Macalloy claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In physics, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Macalloy before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Macalloy ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Macalloy

In research: Macalloy appears in physics research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Macalloy in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Macalloy is common in secondary-school and first-year university syllabi. It links to neighbouring topics British companies established in 1921, Companies based in South Yorkshire, Dinnington, South Yorkshire, so understanding it makes those chapters shorter.
In everyday life: Look for Macalloy outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Ask Teacher Smith questions about this articleOpens your AI tutor with a question about “Macalloy” →

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Macalloy in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Macalloy means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Macalloy out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Macalloy in simple terms?

Why does Macalloy matter?

Because it connects several physics ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Macalloy?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Macalloy.