Structural Engineering Material Choices

ASTM vs ASME – What Every Engineer Should Know 🔥 In engineering, materials, and construction, standards are the backbone of safety, quality, and reliability. Two globally recognized organizations—ASTM International and ASME—play a crucial role, but their focus and applications differ. 🏛 History & Development: ASTM (Founded in 1898) → Develops material standards and testing methods. ASME (Founded in 1880) → Develops engineering codes for safe design & construction of boilers, pressure vessels, and pipelines. 🎯 Purpose: ASTM → Standards & specifications for materials, testing, and products. ASME → Codes & regulations for safe design, fabrication, and inspection. 🔧 Areas of Application: ✅ ASTM (Materials & Testing): Construction (steel, cement, concrete) Petroleum & chemicals (fuels, oils) Electronics & aerospace (metals, plastics, composites) Environment (air, water, soil monitoring) Global trade & manufacturing ✅ ASME (Design & Safety): Pressure vessels & boilers (rules for tanks, piping, pressure systems) Pipelines (B31 series) Power plants & energy systems Oil, gas & chemical plants Mechanical compliance & safety codes 📑 Types of Standards: ASTM Example: ASTM A106 (Seamless Carbon Steel Pipe) ASME Example: ASME Section VIII (Boiler & Pressure Vessel Code) 🧭 How to Choose? Go with ASTM ➝ When your focus is on material composition, testing & product quality. Go with ASME ➝ When your focus is on engineering design, fabrication & compliance. ⚖️ Challenges: Overlap & Misinterpretation → Engineers often confuse which standard applies where. Global Compliance → Aligning ASTM & ASME requirements across countries can be complex. Implementation Costs → Testing, certification, and compliance can add significant project costs. Continuous Updates → Both standards evolve, requiring professionals to stay up to date. 💡 Key Takeaways: ASTM = “What material and how to test it.” ASME = “How to design, build, and inspect safely.” Both are complementary → ASTM defines the material & testing, ASME defines the design & safety framework. Right selection = Better compliance, reduced risks, and safer projects. 🔑 Bottom Line: ASTM = “What material and how to test it.” ASME = “How to design, build, and inspect safely.” ==== Follow me at Govind Tiwari,PhD #astm #asme #qms #iso9001 #quality #qa #qc

Drexel University researchers developed building materials inspired by elephant and jackrabbit ears that can passively regulate temperature. The concrete contains vascular networks filled with paraffin-based phase-change material that absorbs heat when warm and releases it when cool. Buildings consume nearly 40% of all energy, with half spent on temperature control. The most effective design uses diamond-shaped channel patterns that slow surface heating/cooling to 1-1.25°C per hour while maintaining structural integrity. This biomimetic approach could significantly reduce HVAC energy demands, addressing the 63% of building energy loss through walls, floors, and ceilings.

Glad to share our latest research on the design and fabrication of a cable-supported, unreinforced and re-assemblable 3D-printed concrete structure using multi-material topology optimization. The full paper has been published in the Additive Manufacturing journal and is available here: https://lnkd.in/grAViSCe Project team: Yu Li, Hao Wu, Xinjie Xie, Liming Zhang, Philip F. Yuan of Tongji University and Yi Min 'Mike' Xie of RMIT University Centre for Innovative Structures and Materials. #topologyoptimization #digitaldesign #generativedesign #computationaldesign #additivemanufacturing #3dprinting #3dcp #digitalfabrication #architecturedesign #structuraldesign #concrete #steel #cable #assembly Spatial Structures IASS 2023 IASS 2024

Glass Transition Temperature (Tg) - A Key to Material Behaviour! Ever noticed how a plastic component can become brittle in cold weather or more pliable when heated? This phenomenon is often governed by the Glass Transition Temperature (Tg), a key property for understanding amorphous materials, especially polymers. 🔍 Deep Dive into Tg: Tg isn't a sharp melting point like in crystalline materials. Instead, it's a temperature range where an amorphous solid transitions from a rigid, glassy state (below Tg) to a more flexible, rubbery state (above Tg). This transition reflects the onset of cooperative molecular motion. Below Tg, polymer chains have limited movement, while above, they gain enough energy to slide past each other. 🔬 Why Tg Matters in Real-World Applications: Performance Optimization: Knowing Tg helps predict how materials will behave under varying temperatures, crucial for applications ranging from automotive parts to medical devices. Manufacturing Precision: Tg dictates processing conditions like molding temperatures and annealing cycles, ensuring product quality and consistency. Material Selection: Engineers use Tg to select materials that meet specific temperature requirements, preventing failures and enhancing product longevity. 🛠️ Advanced Techniques for Tg Determination: Differential Scanning Calorimetry (DSC): Measures heat flow differences, revealing the subtle energy changes associated with the glass transition. It’s excellent for routine analysis and comparing materials. Dynamic Mechanical Analysis (DMA): Applies oscillating forces, measuring the material’s viscoelastic response. This technique is highly sensitive to molecular relaxations and provides insights into storage and loss moduli. Thermomechanical Analysis (TMA): Tracks dimensional changes with temperature, revealing thermal expansion and contraction behaviour. This is valuable for predicting dimensional stability and identifying Tg through changes in the expansion coefficient. 💡 Key Factors Influencing Tg: Polymer Architecture: Molecular weight, branching, and crosslinking density significantly impact chain mobility and, therefore, Tg. External Factors: Heating/cooling rates, plasticizers, and even ambient moisture can shift the observed Tg, highlighting the importance of controlled testing environments. Composition: In copolymers or blends, the relative amounts of different components will greatly affect the final Tg value. Understanding Tg is vital for engineers, material scientists, and anyone involved in product development. By mastering this concept, we can design more robust, reliable, and innovative products. #materialscience #polymerscience #polymercharacterization #viscoelasticity

Hollow Slabs to reduce weight In construction, maximum weight of a structure is due to the slabs. There are various ways to reduce the weight of such concrete slabs. One such approach involves leaving the space between top layer and bottom layer of thr slab open that would normally be occupied by concrete, or filling it with a lighter material such as ceramic bricks or expanded polystyrene. Another approach, developed in the 1990s by Jorgen Bruenig in Denmark, is to use biaxial hollow slabs, which are now commonly known as BubbleDeck. This system is made up of hollow spheres made of plastic, which are inserted uniformly between upper and lower steel reinforcements. These spheres fill the space that would otherwise be occupied by concrete that serves little structural function but may add significant weight. By using this system, it is possible to reduce the weight of a slab by 25% to 35% compared to a solid slab of the same thickness. This reduction in weight allows for larger spans, reduces the cross- section of the columns, and decreases the overload on the building's foundations. It is estimated that using 1 kg of plastic for the spheres can save about 100 kg of concrete. However, thus system may increase the depth of slabs.

Stronger Than Steel, Lighter Than Iron: Meet the Material That Could Reshape Construction Imagine a building material that doesn’t rust, weighs a fraction of traditional steel, and is twice as strong in tension. It’s not science fiction — it’s Glass Fiber Reinforced Polymer (GFRP), and it may just be the future of global construction. 4x lighter than iron 2x the tensile strength of steel Doesn’t corrode — ever Non-conductive Up to 30% more cost-efficient in projects Used today in everything from roofs, columns, and slabs to marine ports and garages, GFRP is proving itself to be tough, versatile, and built to last. With only 130 kg of fiber replacing a full ton of steel, this innovation drastically reduces structural weight — and boosts sustainability. Already backed by international certifications and Building Research Centre approvals, GFRP isn’t just a smart choice — it’s a next-generation leap in engineering. The era of rust-proof, high-performance construction is here. And it’s lighter than you think.

Here is a general overview of the key aspects of tank construction according to API 650: 𝗗𝗲𝘀𝗶𝗴𝗻 𝗖𝗼𝗻𝘀𝗶𝗱𝗲𝗿𝗮𝘁𝗶𝗼𝗻𝘀: API 650 provides criteria for the design of welded steel tanks, including considerations such as tank dimensions, shell thickness, roof design, bottom design, and reinforcement requirements. The design should account for factors such as the stored product, operating conditions, seismic loads, wind loads, and other relevant parameters. 𝗠𝗮𝘁𝗲𝗿𝗶𝗮𝗹 𝗦𝗽𝗲𝗰𝗶𝗳𝗶𝗰𝗮𝘁𝗶𝗼𝗻𝘀: API 650 specifies the material requirements for tank construction. This includes the selection of appropriate steel grades, plate thicknesses, welding consumables, and corrosion protection measures. The materials used must meet the specified mechanical and chemical properties to ensure the structural integrity and longevity of the tank. 𝗪𝗲𝗹𝗱𝗶𝗻𝗴 𝗣𝗿𝗼𝗰𝗲𝗱𝘂𝗿𝗲𝘀: API 650 outlines the welding procedures and requirements for tank construction. This includes the qualification of welders, welding processes, preheating and post-weld heat treatment (PWHT) requirements, inspection methods, and acceptance criteria for welded joints. The welding procedures must conform to industry best practices and ensure the integrity of the tank structure. 𝗙𝗮𝗯𝗿𝗶𝗰𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗘𝗿𝗲𝗰𝘁𝗶𝗼𝗻: The fabrication of the tank components, such as the shell plates, roof, and bottom, should be carried out in accordance with API 650 requirements. This involves cutting, forming, and welding the components to the specified dimensions and quality standards. The erection process includes aligning and assembling the tank components on the prepared foundation, ensuring proper fit-up and dimensional accuracy. 𝗡𝗼𝗻𝗱𝗲𝘀𝘁𝗿𝘂𝗰𝘁𝗶𝘃𝗲 𝗘𝘅𝗮𝗺𝗶𝗻𝗮𝘁𝗶𝗼𝗻 (𝗡𝗗𝗘): API 650 mandates specific nondestructive examination methods to assess the quality of welded joints and detect any potential defects or discontinuities. Common NDE techniques include radiographic testing (RT), ultrasonic testing (UT), magnetic particle testing (MT), and visual inspection. The extent and frequency of NDE depend on the tank size, operating conditions, and client requirements. 𝗧𝗲𝘀𝘁𝗶𝗻𝗴 𝗮𝗻𝗱 𝗜𝗻𝘀𝗽𝗲𝗰𝘁𝗶𝗼𝗻: API 650 requires various tests and inspections to be conducted during tank construction. This includes hydrostatic testing to verify the tank's structural integrity and leak tightness. Additionally, visual inspections, dimensional checks, and other quality control measures are performed to ensure compliance with API 650 and project specifications. 𝗖𝗼𝗿𝗿𝗼𝘀𝗶𝗼𝗻 𝗣𝗿𝗼𝘁𝗲𝗰𝘁𝗶𝗼𝗻: API 650 provides recommendations for corrosion protection measures, such as coatings, cathodic protection, or other methods to mitigate corrosion on the tank's interior and exterior surfaces. These measures help extend the tank's service life and maintain the integrity of the stored product. ... #API650 #Tank #Construction

PDX is now the world's largest mass-timber airport. Mass timber as a sustainable building material is definitely not a silver bullet. It's a challenging space given supply chains, and professionals familiar with mass timber are limited by geography. Given that this is in Portland, it makes a ton of sense: Wood is obviously evocative of the Pacific Northwest, and ZGF Architects sourced all of the wood from within 300 miles of the airport. From an embodied carbon standpoint, this design is a big win versus an all-concrete or steel superstructure. Plus, a successful mass timber project could unlock more down the road. The 9-acre, all-wood roof is a feat of engineering. It's beautiful. Timber isn't for everywhere and everyone, but I hope we'll see it more prevalent in more major projects. #realestate #climate #masstimber

Turning apple waste into furniture? Material innovation is being redefined with a groundbreaking vegan-certified leather alternative crafted from upcycled agricultural waste. This innovative material offers a premium, bio-based option that seamlessly blends environmental responsibility with practical versatility. Manufactured on wide rolls, it provides a luxurious, durable alternative to traditional leather while addressing the urgent need for eco-friendly solutions. By utilising by-products of agricultural processes, this innovation exemplifies how waste can become a cornerstone for transformative design, challenging industry norms and fostering a more circular economy. Recently, this material has been introduced in the furniture sector, demonstrating its versatility and effectiveness in reducing carbon footprints. For example, when used in furniture, it achieves significant reductions in carbon emissions compared to traditional materials. This measurable impact highlights the potential of sustainable materials to advance both environmental and business objectives. Key Features of Bio-Based Materials →Transformative Origins: Converts agricultural by-products into high-quality materials. →Cross-Industry Applications: Ideal for furniture, fashion, and automotive sectors. →Design Customisation: Supports diverse finishes and textures, meeting unique design needs. →Supply Chain Transparency: Offers full traceability, ensuring ethical production and enhancing storytelling. Business Impact and ROI →Sustainability Leadership: Collaborating with material innovators demonstrates a commitment to Environmental, Social, and Governance (ESG) goals. →Cost Optimisation: By utilising waste-based inputs, businesses can reduce dependence on costly, resource-intensive materials. →Market Differentiation: Offering products made with innovative materials positions companies as leaders in sustainability, appealing to a conscientious consumer base. →Carbon Reduction: Bio-based materials deliver tangible emissions savings, supporting corporate decarbonisation objectives. This innovation exemplifies how rethinking waste can drive sustainability and profitability, empowering businesses to lead in the era of bio-based innovation. Link for more info: https://lnkd.in/dmtMrnP3 #sustainability #esg #biomaterials #decarbonisation #wasteupcycling #innovation #bioeconomy #climateaction #circularity #greendesign

𝗦𝘁𝗲𝗲𝗹 𝘃𝘀 𝗔𝗹𝘂𝗺𝗶𝗻𝗶𝘂𝗺: 𝗪𝗵𝗲𝗻 𝘁𝗼 𝗣𝗶𝗰𝗸 𝗪𝗵𝗶𝗰𝗵 𝗮𝗻𝗱 𝗪𝗵𝘆 𝗜𝘁 𝗠𝗮𝘁𝘁𝗲𝗿𝘀 -- 1️⃣ 𝗠𝗮𝘁𝗲𝗿𝗶𝗮𝗹-𝗦𝗲𝗹𝗲𝗰𝘁𝗶𝗼𝗻 𝗖𝗵𝗲𝗮𝘁 𝗦𝗵𝗲𝗲𝘁 1. 𝗦𝘁𝗿𝗲𝗻𝗴𝘁𝗵-𝘁𝗼-𝗪𝗲𝗶𝗴𝗵𝘁 𝗥𝗮𝘁𝗶𝗼  Aluminium’s 3× higher specific strength lets you shave kilograms where mass = money (fuel, launch, shipping). 2. 𝗦𝘁𝗶𝗳𝗳𝗻𝗲𝘀𝘀 (𝗠𝗼𝗱𝘂𝗹𝘂𝘀 𝗼𝗳 𝗘𝗹𝗮𝘀𝘁𝗶𝗰𝗶𝘁𝘆) Steel is ~3× stiffer, critical for keeping deflections small in thin sections. 3. 𝗙𝗮𝘁𝗶𝗴𝘂𝗲 & 𝗜𝗺𝗽𝗮𝗰𝘁 High-strength steels excel in crack-growth resistance; aluminium needs larger radii, anodising or shot-peen to match. 4. 𝗖𝗼𝗿𝗿𝗼𝘀𝗶𝗼𝗻 𝗕𝗲𝗵𝗮𝘃𝗶𝗼𝘂𝗿 Aluminium self-passivates; steel demands coatings or stainless grades if you hate rust budgets. 5. 𝗧𝗵𝗲𝗿𝗺𝗮𝗹 𝗖𝗼𝗻𝗱𝘂𝗰𝘁𝗶𝘃𝗶𝘁𝘆 Aluminium spreads heat 4–5× faster - gold for heat sinks, battery trays, cookware. 6. 𝗙𝗼𝗿𝗺𝗮𝗯𝗶𝗹𝗶𝘁𝘆 & 𝗝𝗼𝗶𝗻𝗮𝗯𝗶𝗹𝗶𝘁𝘆 Steel bends deeper without spring-back; aluminium welds easily but hates galling—design around it. 7. 𝗥𝗲𝗰𝘆𝗰𝗹𝗮𝗯𝗶𝗹𝗶𝘁𝘆 & 𝗖𝗢𝟮 𝗙𝗼𝗼𝘁𝗽𝗿𝗶𝗻𝘁 Both loop well, but recycling aluminium saves ≈ 95 % of primary energy, helping ESG scorecards. 8. 𝗖𝗼𝘀𝘁 & 𝗔𝘃𝗮𝗶𝗹𝗮𝗯𝗶𝗹𝗶𝘁𝘆 Raw steel (mild) sits ~₹70–80 /kg; automotive aluminium sheet ~₹240–300 /kg in India (June 2025). Aluminium cuts quicker, needs less tooling wear. -- 2️⃣ 𝗥𝗲𝗮𝗹-𝗪𝗼𝗿𝗹𝗱 𝗖𝗮𝗹𝗹𝘀 𝗬𝗼𝘂’𝗹𝗹 𝗥𝗲𝗰𝗼𝗴𝗻𝗶𝘀𝗲 🚗 𝗔𝘂𝘁𝗼𝗺𝗼𝘁𝗶𝘃𝗲  • 𝗖𝗿𝗮𝘀𝗵 𝗿𝗮𝗶𝗹𝘀: 6000-series aluminium extrusions absorb energy while slashing 30 % weight.  • 𝗖𝗵𝗮𝘀𝘀𝗶𝘀 𝗰𝗿𝗼𝘀𝘀-𝗺𝗲𝗺𝗯𝗲𝗿𝘀: high-strength low-alloy (HSLA) steel keeps stiffness for NVH control. ✈️ 𝗔𝗲𝗿𝗼𝘀𝗽𝗮𝗰𝗲  • 𝗙𝘂𝘀𝗲𝗹𝗮𝗴𝗲 𝘀𝗸𝗶𝗻𝘀: 2024-T3 and 7075-T6 aluminium alloys dominate for fatigue and weight. 🏠 𝗛𝗼𝗺𝗲 𝗔𝗽𝗽𝗹𝗶𝗮𝗻𝗰𝗲𝘀  • 𝗥𝗲𝗳𝗿𝗶𝗴𝗲𝗿𝗮𝘁𝗼𝗿 𝗹𝗶𝗻𝗲𝗿𝘀: galvanised or coated steel for dent resistance.  • 𝗣𝗿𝗲𝗺𝗶𝘂𝗺 𝘄𝗮𝘀𝗵𝗶𝗻𝗴-𝗺𝗮𝗰𝗵𝗶𝗻𝗲 𝗱𝗿𝘂𝗺𝘀: spun aluminium for quieter cycles and rust-proof longevity. -- 3️⃣ 𝗖𝗼𝘀𝘁 𝗜𝗻𝘀𝗶𝗴𝗵𝘁𝘀 𝗧𝗵𝗮𝘁 𝗧𝗿𝗶𝗽 𝗗𝗲𝘀𝗶𝗴𝗻𝗲𝗿𝘀 𝗧𝗼𝘁𝗮𝗹-𝗹𝗮𝗻𝗱𝗲𝗱 𝗰𝗼𝘀𝘁 = 𝗿𝗮𝘄 𝗽𝗿𝗶𝗰𝗲: die cast Al housing can beat welded steel + paint after you tally machining, corrosion coating, and logistics. 𝗦𝗰𝗿𝗮𝗽 𝘃𝗮𝗹𝘂𝗲: Aluminium chips fetch ~₹145 /kg; steel turnings ~₹25 /kg- recycling rebates can tilt the ROI. 𝗩𝗼𝗹𝘂𝗺𝗲 𝗽𝗲𝗻𝗮𝗹𝘁𝘆: Steel’s higher density means bigger shipping weight, but aluminium’s 30–40 % material surcharge looms in low-volume runs. Run that spreadsheet! -- 🎯 𝗧𝗮𝗸𝗲𝗮𝘄𝗮𝘆 𝗣𝗶𝗰𝗸 𝘀𝘁𝗲𝗲𝗹 when you need ultimate stiffness, dent resistance, or budget simplicity. 𝗖𝗵𝗼𝗼𝘀𝗲 𝗮𝗹𝘂𝗺𝗶𝗻𝗶𝘂𝗺 when every gram hurts or heat must flow freely. Mix intelligently—smart multi-material design often beats “either-or.” -- #engineering #ProductDesign #mechanical #design #sheetmetal #caddesign #automotive #aerospace