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Engineering Articles - CalcTree

Steel Design Rules of Thumb for Structural Engineers

Cement 101: What you need to know about this major construction material and it’s alternatives

High strength structural steel and Its Properties

Essential Knowledge for Structural Engineers: Skills and Expertise

Australia's Top Stadiums: Engineer's Perspective

OpenSeesPy vs ETABS: 2D Frame Modal Analysis Comparison

Get started with OpenSees on CalcTree

Enhance your knowledge and stay up-to-date with the latest trends and innovations in structural engineering with our articles and resources. 

Structural Engineering Articals & Resources

Have you ever been in a meeting with an architect, and they’ve asked you if they can extend a beam here or remove a column there? What grid spacing will and won’t work, or how big does the core really need to be? 

Well, before you spin up a new Etabs model and spend 3 hours trying to answer that question, there’s a better and faster way to provide some high-level advice on the spot: by using rules of thumb!

While rules of thumb aren’t always applicable and should only be used as a guide and approximation, we thought it’d be helpful to list out the most essential rules in an article for your reference! Enoy! 

1) Space columns using a primary-to-secondary beam length ratio of 3:4

The logic for this is that primary members typically take more load and work harder than secondary members. So it’s advantageous to reduce their effective lengths. Primary members will typically be far larger than secondaries, so positioning them in this way reduces material usage regarding section sizes and connection heft.

Introduce thermal expansion and contraction joints every 150m (~500ft) each way

Using simulation software, the exact spacing and position of expansion joints can and should be determined for specific materials, conditions and structural layouts. 

ensuring expansion joints at every 150m in both directions of a structure

 will be in the ballpark of what's required. 


Using this rule of thumb and applying it to your drawings or reports and, therefore, in project costings will save you a headache down the line!

4) Typically, steel structures will be deflection governed

In most cases, steel structures will be deflection-governed, so it's important to know you're deflection equations. 

 a handy beam analysis and deflection tool to calculate deflection on the go!

5) Span to Depth ratios for steel framing 

Frequency can be estimated from the deflection at mid-span. 

. The shorter it is, the less stiff the structure is and the more likely it is that an occupant may experience vibration.

7) In most cases, continuous members are preferable to simply supported members

This is because it not only can balance out moments, as per rule 2 above, but it also reduces your design’s susceptibility to vibration. Having continuous members allows more mass to be engaged under excitation and dampens vibrations.

Note that this assessment doesn't account for additional connection complexity and requirements. This aspect of your design must also be considered before coming to a conclusion.

8) Camber out a maximum of 80% of deadload

While cambering beam is a powerful tool for permanent load deflections, over-cambering is dangerous. It can lead to a beam element having a permanent 'hog' in it, and/or it can drive vibration issues.

So limiting your cambering to 80% of total dead load deflection, reduces the risk of over-cambering.

9) Span to Depth ratios for composite beams 

10) Composite structural steel self-weight ~70-75% of a non-composite steel structure

Yup, this is the saving you'll see in tonnage due to using composite steel! 

Keep in mind that there's always a trade-off. In this case, you'll need to allow for composite studs and decking trays in a composite design.

Locate smaller circular penetrations close to inflection points where V* is close to 0 and M* is low. 

For typical simply supported beams, this will be at ⅓ points along the length of the member.

12) Locate penetrations in the middle of the beam where the shear is low, and include top and bottom plates for large openings

Place penetrations in the middle of the beam web, and make sure to include allowance for plates on the top and 

The plates allow you to maintain moment capacity while taking advantage of lower shear demand in this part of the beam.

Space penetrations with a minimum of 2 x beam depth between each penetration. 

This is to maintain integrity in the beam web, and allow transfer of shear as consistently as possible along the beam.

An approximation of how many levels a column can support when spaced at typical grids (as per rule 1).

All other things being equal, a deeper wide-flange beam will be more economical than a shallower one.

Don't believe us? Compare your members performance using our 

For a fly brace or secondary member to provide lateral restraint to another member it connects to, it must have a capacity of at least the order of 2.5% of the maximum compressive force in the restrained member, in the transverse direction of the restrained member or compression flange.

See AS4100 cl 5.4.3 for more details on this one.

Check if your member has enough capacity to restrain using our 

”. In other words, the upper flange of the purlin should be pointing up the roof's slope.

Our detailed design guide has much more detailed information on 

18) Portal Frames - standard span-to-depth ratios

19) Apex haunches should run for about 1/8L of the beam span

At their maximum depth, the haunch should roughly match the depth of the rafter beam.

20) Roof pitch should be 2-3 Degrees depending on specific code and drainage requirements

You should also double-check the code, but if you need a number in a pinch, then you can estimate 2 to 3 degrees for a standard roof pitch.

You should always aim to use M20 bolts and 8.8/S grade and fit as a first pass. 

This is because they're cheap and the most common, they also don't require any specialist equipment to install.

Generally, you should match the web thickness of the connecting member.

Number of bolts to use for a regular connection

But when you need a more detailed answer, you can use our 

Discover Steel Design Rules of Thumb for Structural Engineers. Unlock valuable insights for your projects. Explore now!

Rules Of Thumb For Steel Design

Concrete is, without a doubt, one of the most widely used construction materials. After all, large cities lined with towering skyscrapers are known to be concrete jungles for a reason. The carefully curated mixture of cement, water and aggregates form the structures of many buildings around us today. This isn’t much of a surprise, given concrete is highly durable, economical and an increasingly sustainable construction material. For more info on sustainable materials and concrete, check out more articles on 

While concrete is becoming more sustainable, we aren’t at a stage where concrete production is carbon neutral, but there is research into alternate cement types and efficient cement production processes. To understand how concrete ties into sustainability, we have to dive a bit deeper into the workings of cement, the core ingredient that forms concrete.

Cement is a fine powder that, when mixed with water, undergoes a hydration reaction to form a binding paste. It is then combined with a mixture of coarse and fine aggregates to create the concrete we use in construction.

Cement powder is generally made from lime, silica, alumina and iron oxide [1]. The raw minerals are mined and processed through a rotary kiln, as is in the case of the most commonly used Portland Cement. The rotary kiln dries the mixture of raw materials. It produces clinker by subjecting the raw materials to high enough temperatures that the chemical bonds break apart and reform. This can be achieved either through the Wet Process, whereby the minerals are supplied as a wet slurry, or the preferred Dry Process, where minerals are provided as a dry mixture and preheated before entering the kiln [1]

After the clinker is produced from the rotary kiln, it is cooled, grounded and mixed with gypsum and other admixtures to form the final cement powder. The final product mainly consists of calcium silicates and aluminates [2]. The proportion of clinker present in the cement to gypsum and other constituent minerals defines the final properties of the cement and the concrete it produces.

The types of cement we commonly use in construction

Cement used in construction is typically classified by its physical properties, which come from the way they are manufactured and its constituent minerals. The standard designation of cement is based on several factors [2]:

From AS 3972, cement is grouped into six major types across two categories

Predominantly Portland clinker mixed with gypsum with up to 5% of a secondary additive as approved by AS 3972. They are cost-effective and good in most construction practices that don’t require special properties such as high acid or water resistance [3]

It is a blend of Portland cement with either fly ash or slag. Similarly to Type GP cement, blended cement applies to a wide range of large and small-scale construction. It brings the benefits of increased workability at a lower water demand and better resistance to sulphate attack [4].

Type HE concrete is generally used for suspended slabs or precast structures where the building structure needs to be serviced quickly [5].

 Ideal for mass concrete pours with lower heat liberation. The cement is formed from cement, gypsum and granulated blast furnace slag to generate minimal heat during cement hydration. LH cement is usually mixed at a high cement-to-water ratio to maximise concrete life expectancy [6].

Type SR cement reduces the chances of sulfate attacks by reducing the presence of sulfate salts in the mix. Tricalcium aluminate (C3A) is limited to a maximum of 5%, and the cement compound of 2C.3A + C4AF to 25%. SR cement is resistant in highly acidic environments and can lower the risk of corrosion in steel reinforcement [7].

Type SL cement is a type of Portland cement with up to 7.5% of additive approved by AS 3972 to be applied in works requiring lower drying shrinkage. The performance of the cement ensures shrinkage stays well within the specified limit of 750 microstain at 28 days from AS 3972 [8].

Cement is typically used for its high compressive strength. It does, however, suffer from a far weaker tensile strength, hence why concrete structures are typically accompanied by steel reinforcement. Steel is strong in tension and compression, meaning that it can compensate for the lack of tensile strength in concrete.

Properties of Ordinary Portland Cement Paste [9]:

Properties of Ordinary Portland Cement concrete [10]:

Chemical symbols used in the notation for cement compounds are abbreviated accordingly [11]:

The four main compounds of Portland cement are [11]:

How do these chemical compounds contribute to cement properties?

Alites in Portland cement are mainly responsible for determining the initial strength of concrete in the first week of hardening. Belite determines the hardening of the concrete in the remainder of the 28 days of concrete hardening.

Concrete formation involves mixing cement with water, fine aggregates and coarse aggregates. Cement serves as the adhesive to concrete, binding all the materials together. However, it lacks material strength, resulting in weak tensile strength of concrete. The aggregates are the components that determine the compressive strength of concrete instead [12]. Coarse aggregates support the majority of compressive loading. Sand contributes to compressive strength as well but serves mainly to fill in the gaps of the crushed aggregates. Finally, water mixes with cement to help bind all the materials together and provides the workability of concrete during construction. Below are the associated mixing ratios for different concrete strength grades and their applications [13]: 

Table (2)

Remember how in the beginning, we mentioned concrete is becoming more sustainable? Yes, there is plenty of discourse on the sustainability of concrete in construction, and a big concern is centered around cement manufacturing.

During the production of Portland cement, the kiln is heated up to 1450 degrees Celsius, which requires large amounts of energy. At this stage, calcination occurs in the mixture of minerals. The calcium carbonate within the limestones is converted to calcium oxide, producing carbon dioxide as a byproduct and releasing it. The empirical expression for this reaction is as shown:

Producing 1 tonne of Portland clinker will also directly yield 0.55 tonne of carbon dioxide gas as a product [14].

Let's consider the amount of fuel it needs to generate the energy to raise the kiln to 1450 degrees Celsius. We are looking at about another 0.40 tonne of extra carbon dioxide produced. This would mean an associated 0.95 tonne of carbon dioxide per tonne of Portland clinker produced.

This process alone accounts for half of the carbon emissions in cement production and 4% of the globe’s total carbon emissions. The other half of carbon emissions in cement production comes from creating energy to fuel the process [15].

It’s a given that sustainability is a big issue within the construction industry. So, what’s the solution?

There are two ways we can tackle it: we either reduce carbon emissions by addressing the carbon in the materials or reduce the carbon from production.

Let’s go with the latter first. There is a rising carbon minimisation strategy in the form of Carbon Capture and Storage (CCS). The idea is to capture all the carbon dioxide released in the cement production process and transport them to an underground storage system [16]. The process involves combusting the fuel in oxygen to allow for the greatest concentration of CO2 in its emissions. The emissions are then captured and compressed into a liquid before finally getting transported through pipelines into the storage system. 

There are some limitations to this method. CCS does not rid cement production of carbon dioxide entirely as well as CCS has yet to be tested on an industrial scale. About 72-90% of CO2 is produced, with the remainder coming from energy costs.

If Portland cement isn’t the way to go, what will it be?

Hope is far from lost. While Portland cement is still the most popular cement option in construction, we currently have areas where we can continue towards a carbon-neutral future. One answer is geopolymer cement. Geopolymer is made from alkali aluminosilicate in waste materials being put through polycondensation [15]. Such materials include fly ash from coal burning, ground-granulated blast-furnace slag and clay, all of which are abundant in Australia.

Compared to Portland cement, geopolymer concrete produces up to 80% fewer carbon emissions as it does not rely on calcium carbonate [14]. It also primarily uses the waste materials mentioned above instead of raw minerals.

Geopolymer cement also has performance benefits in the production of concrete and construction. Initial and final setting times increase as the cement is produced with a high alkali concentration. Its initial compressive strengths are lower than Ordinary Portland Cement. However, strength increases through concrete ageing. It has been shown that final compressive strength can match up to that of Portland Cement and, at times, even higher strengths [17].

Research around geopolymer cement and sustainable concrete has been conducted in the construction industry for a while. We are still transitioning into a future that is less reliant on Portland cement. It’s not an easy path, for sure. Still, there are plans and studies on integrating more environmentally friendly cement into the industry from an engineering and business perspective.

These strategies lead Australia to a carbon-neutral future for cement production and beyond.

A report by Beyond Zero Emissions in 2017 proposes a 5-step process by which Australia can transition our cement production to a carbon-neutral future with the possibility to venture into carbon-negativity [15].

 Geopolymer cement does not require a kiln, and the cost of a plant costs 10% of a Portland cement plant. These clays are produced from fly ash and ground-granulated blast-furnace slag or clay, all currently made in Australia. This stage will replace half of the current cement market.

Blending Portland cement with other materials will reduce its cement intensity and assist with a transitioning phase in decarbonisation. Other materials, such as fly ash, slag, and clay, make up 70% of the final cement. This stage will replace the remaining half of the current cement market.

 Unlike Carbon Capture and Storage (CCS), carbon waste from Portland cement production is captured and chemically sealed within a rock. This prevents the risk of leakage or post-capture monitoring. The carbonated mineral can produce commercial materials such as magnesium carbonate and silica. This seeks to reduce Portland cement emissions to zero.

 Reduce cement usage by efficiently designing concrete structures. This can be done using high-strength concrete or incorporating timber into design structures. An outcome of a 15% reduction in cement usage is expected.

Strategy 5 - Use of carbon-negative cement: 

This strategy aims to bring cement production to a carbon-negative era. Magnesium-based cement has the potential to absorb carbon over time to become a carbon sink. Research is still being performed in this area, and commercialisation will be the desired outcome.

Learn all you need to know about cement, it's chemistry, applications and the road to sustainability. 

Learn all about cement's material properties, chemistry and it’s alternatives

High Strength Steels (HSS) and Ultra-High Strength Steels (UHSS) have recently made quite a splash. However, growing site constraints, construction demands, taller buildings, and longer-spanning bridges have necessitated enhancements in the mechanical and behavioural properties of materials.  

To date, HSS and UHSS have primarily been used in the automotive and crane manufacturing industries. But recently, they’ve become increasingly common in Civil Engineering applications, primarily due to their exceptional mechanical strengths and material efficiency. The possibility of designing lighter and simplifying the transport of steel components through HSS integration into designs is the kind of good news we’ve been looking for! With HSS, the strength-to-weight ratio increases, resulting in lighter, leaner, and simpler fabrication and construction. The prospect of longer spans, net-weight reductions, greater load-carrying capacities, and reduced material usage are benefits engineers are keen to exploit.

 with higher yield stress allowance to see the difference in section sizes with HSS.

Bridge spans are increasing, tunnels are getting longer (check out the 

 to see a great example), and building designs are becoming leaner. These modern design requirements are increasing the performance demand on structural materials. HSS's enhanced physical and sustainable credentials have accelerated its use in contemporary design and have increased demand for HSS products. Combined with that, an attractive 30% steel saving for most types of HSS applications compared to conventional steel will leave you asking why is HSS not being used everywhere.

Well, not so fast; there’s still a lack of research on HSS’s structural performance under certain conditions, particularly at elevated temperatures [1].  Most international design standards don’t even cover HSS design, which means the adoption of HSS products is pretty limited. Further analysis and research are needed before HSS can become ubiquitous in the industry. 

HSS will eventually become a key tool in any civil engineer’s toolbox despite the hold-ups, so it’s important to know when to consider using it. Below we break down everything you need to know about HSS, where to use them, and what to look for when designing them. 

 when they possess yield stress above 460 MPa up to 690 MPa. Steels with yield stress above 690 MPa are considered 

HSS and UHSS are used at an elementary level to make a wide array of structural members, from columns, beams, plates, and bolts to increasing hybrid applications. Common fabricated HSS sections include I/H sections, box sections, and tubular sections. To capitalize on substantial weight savings over conventional steel grades, hybrid elements containing HSS are becoming increasingly popular. Some examples of these include:

Behaviour & properties of high strength steel

High Strength Steels exhibit many different mechanical proprieties compared to ordinary steels; higher yield strength, higher yield-to-tensile strength ratio, better tensile stress, bending, and weld performance. Before getting to these differences in more detail, let’s lay out the key general mechanical characteristics of structural steels first:

Below, we’ll briefly go through each of these factors for HSS to assess their practical application over commonly used mild steels.

HSS has a higher yield strength than mild steel, yet the Modulus of Elasticity (E) is constant for all steel grades. This limits the deformation capacity of HSS, leading to potential issues concerning serviceability and stability. These issues primarily concern local strength and stiffness degradation that can impact global structural integrity, building sway, and member deflections. 

When HSS is specified in structural components, considerations must be made concerning the increased likelihood of stability problems, mainly when 

 are involved. Serviceability considerations, like deflection criteria, usually govern design criteria in buildings. Further, structural integrity in buildings is achieved chiefly through appropriate 

, which is not dictated by material strength but likely by factors like modulus of elasticity, support configurations, or the type of structural system or loading conditions. Even if HSS can carry more load due to its advances in material strength, its performance is often still limited by member deflection, so simple increases in strength may not be sufficient or economical[2]. For bridges, this is not always the case; fatigue and fracture criteria usually govern design requirements, so HSS could likely be more suited to bridge applications. 

High-strength steels exhibit superior ductility properties over mild steel by the measure of elongation.  Ductility in steel measures its ability to plastically deform under tensile stresses. Imagine a game of tug-of-war on a steel element, its ability to deform and stretch without becoming weak, brittle, or fracturing all refers to its ductility. Similarly, steel ductility enables structures to resist deformation from tremors or earthquakes, by dissipating the energy produced through plastic yielding. Ductility is also crucial during fabrication, allowing it to redistribute stresses and reduce cracks induced through welding, bending, and straightening of the steel.

Tests on HSS are typically measured through elongation at the yield of a steel specimen under high-loading events. Rotation capacities can reveal whether steels satisfy seismic and deformation demands. Recent research has shown that HSS steels achieve uniaxial elongations between 18-30%, deemed excellent [2].

However, experimental and numerical studies have revealed that HSS members could demonstrate poorer ductility under seismic loading due to higher yield-tensile strength and lower deformation capacity than mild steels. Despite some promises in ductility properties, before HSS steels can be applied broadly, current seismic design specifications within national standards need to be revised to accommodate HSS. 

When a whole steel section is subjected to compression, the strength of the steel member can be weakened in bending; this is overall buckling. Studies have shown that the overall buckling behavior of HSS elements and conventional mild steel can vary widely given differing geometric imperfections, residual stresses, and material properties within cross-sections. Despite this, the overall buckling strength of HSS is significantly higher than ordinary steel (you can test this theory out with our 

). However, using more slender sections means that stability issues like overall or local buckling remain a primary failure mode for HSS elements. Furthermore, since HSS elements tend to be thinner and if subject to the same load as an ordinary steel element, they are more likely to experience buckling [3].

Local buckling is due to compression in plate elements such as flanges or webs of an I beam. Conventionally, local buckling is controlled by making sections more compact.

Applying HSS in structures can lead to thinner, lighter, and longer sections aiming to achieve more economical solutions. As such, plate elements in HSS members tend to be thinner and wider than ordinary steel members.

The higher strength of HSS and UHSS steels allows for more slender sections with different slenderness limits to be utilized as structural components. However, this often means that local buckling would become the governing design criterion rather than the ultimate bearing capacity. Research has been done on improving local buckling and a post-local-buckling load of HSS sections by infilling sections with concrete, a potential (but expensive) solution to stability concerns [4]. 

Weldability refers to steel's ability to weld/join with similar materials. Steels require an appropriate chemical composition to improve weldability without propagating cracks and other imperfections. Filler metal selection can be an important consideration, but how the welding process affects the steel should be of particular focus. As metals change from liquid to solid during the welding process, stress is introduced in the weld as it shrinks and in the steel. It is the nature of these stresses on steel elements made of HSS (which tend to be longer and thinner), that needs to be looked into further. This can be done through careful heat and cooling, appropriate weld joint design, and low hydrogen or low alloy-metal cored or flux-cored filler metals[5], however, it introduces additional cost into the process.

HSS has superior weldability when subjected to proper heat treatment and filler, resulting in finished welds that are very strong. However, HSS can often be more susceptible to cracking over mild steels, so the welding process can be challenging, especially during the rapid heating and cooling process, requiring good heat treatment before and during welding; in other words, it's got to beat the heat! [6] 

Fracture toughness refers to a steel’s capacity to resist failure after the propagation of a crack. This mechanical property is significant for bridges, where fatigue cracking is prevalent due to repetitive and cyclical loading and service conditions.  

As a result of limits in steel processing technology, HSS can exhibit lower fracture toughness than mild steel. This indicates that the structural performance of steel structures fabricated with HSS can be significantly different from conventional steel structures when subject to dynamic, cyclic, and sudden loads or seismic conditions and should be reflected appropriately in design codes [2]. 

Corrosion can significantly degrade the properties of steel. Corrosion resistance refers to the ability of steel to resist weathering. Corrosion is a significant issue in many geographical locations, particularly for structures where elements are exposed to harsh environmental conditions.

Structural steels, particularly those in marine environments, are susceptible to corrosion. Generally, HSS steels demonstrate slightly better corrosion protection when compared to other steels. However, further research is needed to investigate HSS corrosion behavior, particularly in cyclic environments.

Advantages of using higher strength steels

 that come from implementing HSS depend not only on the type of project but on the desired function and form of the structural element used.

Here are some likely advantages of using HSS steels in structural contexts:

High-strength steels have primarily been used in 

, with frequent use in the automotive industry. There are, however, a few examples of HSS being used in structural and civil designs around the world. Here are a few:

The Latitude Building in Sydney, Australia, was completed in 2005 and sits on the very bustling George Street at World Square. The iconic 45-floor building was designed by Hyder Consulting and constructed by Multiplex, reaching skyward in high-strength steel for a total height of 222m. The building boasts some innovative composite steel construction. The 7-meter-deep transfer structures used 650 & 690 MPa HSS steel box sections filled with concrete and high-strength tubular sections. Similarly, 650-690 MPa steel plates were implemented for the basement columns and roof trusses. By using HSS in this context, column sizes and excavation costs were reduced, providing additional floor area and car-parking spaces in the building. 

The Sony Centre complex in Berlin is regarded as an iconic landmark at the busy Potsdamer Platz. Designed by Helmut Jahn, the buildings tie together the cultural and business dynamics of the space in a fluid, edgy design. While the roof above the Sony Centre looks like it is floating, it comprises 600 tonnes of steel. Using S690 HSS allowed the designers to achieve the significant weight reduction required to reduce supports and achieve its weightless look. It also enables the roof to be suspended several stories above the building, diverting the additional loading away from the heritage masonry building below and avoiding any strengthening works. 

Not only is this multi-span cable-stayed bridge an aesthetic marvel, but it has also cemented its status as a world record holder. It’s currently the highest bridge in the world, with a total construction height of 343m, crossing the Tarn River at an altitude of 270m. Michel Virlogeux was the leading engineer and civil engineering construction company Effiage constructed the colossal project.

The 2460 m long deck comprises six main spans and two end spans, all over 200 m wide. The bridge’s cross-section is a central box linked to seven steel pylons erected in an inverted Y-shape. Of the 43,000 tonnes of steel plates used, over 18,000 tonnes are HSS elements. HSS S460 steels were used for the entire central box, various girder panels, and erection auxiliaries. The pylons were also constructed from the S460 steel grade. 

The production process of the HSS steel allowed for the attainment of excellent high-strength performance and fantastic weldability. Applying an optimized and efficient welding process meant that time and weight savings were made. Furthermore, the higher strength of steel allowed the structure to resist high loads and bending moments without needing to increase the amount of steel used. Further cost savings were made by reducing transport weights and costs as a result of material savings[7]. Safe to say, this entire project would not have been possible without HSS.

Despite the advantages of implementing either fully fabricated or composite HSS elements in structural applications, the use of steels with nominal yield stress above 460 MPa in broader contexts remains surprisingly low (approximately 5%). While there is immense potential for wider use in building structures, there are some drawbacks engineers should be aware of. The main one is research. 

There are gaps in experimental and numerical research on high-strength steel members' behavior and mechanical properties under varying and dynamic load conditions. For example, the local buckling behavior of HSS members under axial compression or the behavior of HSS under combined bending and axial loads have not been explored thoroughly.

There is even less research relating to the effect of elevated temperature on HSS. We know that steel's strength and elastic modulus drop sharply under elevated temperatures. Quantitative research of HSS under fire conditions is scarce, potentially making these structures something that engineers NEVER want to hear: unpredictable. Disastrous events like the collapse of the World Trade Center (WTC) towers in 2001 were an impetus for increased research activity into the impacts of fire on steel materials and structures. This research is far from over, particularly when HSS is concerned. Further research should not be neglected, and the behavior of HSS elements under fire loading needs to be investigated. 

Finally, the research done on HSS structures provides evidence that the mechanical behavior of HSS structures is different from that of ordinary steel structures, which means that current design methods, codes, and specifications from regulatory bodies are not necessarily applicable to HSS design and most definitely aren’t optimized. Research has shown that current codified practices can sometimes be both too conservative and not safe at the same time, so again, they’re unpredictable. To promote the application of HSS and take advantage of its potentially superior mechanical performance, new design specifications need to be regulated.  

The construction industry is material, labor, and energy-intensive. From having to source raw materials, transport them to the site, and everything in between. This is energy-intensive and contributes heavily to embodied carbon and operational emissions. On top of all of this, what do we do with all the materials in a building when it reaches its end of life? 

The application of high-strength steel in design means that we could use less steel in that design, significantly boosting a project’s economic, sustainability, and efficiency credentials. 

Less resource-intensive designs, quicker fabrication, time and cost savings in loading, transport, and unloading, and shorter supply chains. 

 The application of HSS assumes that strength is the limit state for the design, but as material and element configurations change, so do their mechanical properties and behavior under certain conditions. To fully realize the benefits of using high-strength steels in our buildings necessitates more research, more inputs, and changes implemented by regulatory bodies and more collaboration throughout supply chains. 

 What is CalcTree, we hear you say? And how can CalcTree integrate HSS into engineering designs? We aim to be at the forefront of materials innovation, supporting new and sustainable products within our engineering design services.‍

, the app you're reading this one is a calculation management platform. You can sign-up and build hosted, shareable web apps (complete with an API and a web publishing module) with tools like Python and Spreadsheets. Learn more 

Uncover the Benefits of High Tensile Steel and Its Properties. Learn what is high tensile steel and make smarter choices. Click here for details!

High strength structural steel and Its Properties - CalcTree

Structural engineers are integral in designing and executing our buildings and infrastructure. From residential homes to skyscrapers and from 

, a structural engineer delivers projects that are safe, economical, and made to last. So, what should all structural engineers expect to know? 

 their physics and engineering knowledge to design, assess and improve structures. When it comes to design, a structural design typically has to meet three main requirements: 

Strength, Serviceability, and Durability. 

In other words, a structure must not fail or collapse 

, it must not overly bend, sway, deflect, or vibrate excessively 

, and it must not deteriorate, corrode, or suffer fatigue 

Everything from analyzing structural systems under various loads to satisfying assumptions and allowable limits to determining construction methods and materials, interpreting and drafting plans, specifications, and drawings becomes part of your repertoire.

Structural engineering is a specialisation of Civil Engineering; in other words: All structural engineers are civil engineers, but not all civil engineers are structural engineers.

As a structural engineer, you can expect to focus on more complex structures across various job types and industries. You might find yourself working on structures as varied as skyscrapers, train stations, hospitals, mining and industrial buildings, and large infrastructure projects.

Your design must consider all static and dynamic loads while balancing the requirements defined by developers, operators, architects, builders, services engineers, and more! You'll need to perform advanced calculations and simulations to analyze structural performance and explore options. You must also ensure the design meets all stakeholder requirements and physical and regulatory performance metrics.

On the other hand, civil engineers tend to design and supervise the broader aspects of public infrastructure. A civil engineer working on 

 can expect to deal with anything from road and pavement design to rail systems, landscaping, and drainage. They collaborate with structural engineers and other specialist engineers (like bridge and tunnel engineers) to design broader systems and communicate with stakeholders. They make recommendations and plans, ensure project sites meet performance requirements and respect regulatory standards.

To simplify it even more: civil engineers tend to look at the bigger picture, while structural engineers focus on the complex structural elements of a project.

There are several key groups of knowledge and skillsets that a structural design team needs to do their jobs well. 

Structural engineers must have a firm grasp of physics and the fundamentals of construction to understand how structures are built and behave and how they respond to environmental conditions.

An aptitude for physics, mathematics, and science is a must. These subjects are deeply intertwined into all the concepts you learn as you head into university and the workforce. 

From studying materials and mechanics to hydraulics and geotechnics to project management and, more recently, computer science, a structural engineer needs to be a jack of all trades to do their job well.

Being able to look at a real-life concept of a structure and turn it into an analytical model or free-body diagram is key to the job. Additionally, concepts like moment or torque, shear, and deflection should become second nature. Understanding and considering material properties like elastic modulus, the 

, and their impact on a system's performance are key skills you'll develop as a structural engineer. 

Understanding the individual components of a structure, like columns, beams, slabs, struts, etc., are the building blocks of design. From there, conceptualizing how these components interact to create sub-systems within a structure, like lateral stability systems and floor plates, is also key. 

Building a strong knowledge base about local and national building codes and standards is important too. Understanding and applying codes of practice and typical assumptions are just as important as crunching numbers. 

Knowing your trade also means knowing how it all comes together on-site. Construction processes and how to inspect and evaluate a building site will be a skill you learn on the job. As a structural engineer, you should be able to inspect a building or construction site and compare what you see with the building plans. You will inspect the building envelope, walls, insulation, etc. Discrepancies are then noted and remedied. Finally, identifying defining risk and, therefore, the margins of safety to apply to global and local parts of a structure is the final piece of the puzzle to designing a safe and robust structure.