Engr Ali Kaif Rana 👷🏗️🌇’s Post

In our resilience study of the 200-mile U.S. 74 corridor from Charlotte to Wilmington, NC, we identified asphalt flushing as the major impact from excessive future heat. This is when the asphalt essentially melts and overriding cars pull aggregate from the mix in their tires, resulting in unsafe driving conditions. By end of century it was causing more disruption than all types of flood combined. We didn’t simulate above-design thermal expansion, which is certainly causing disruption here, and significant cost. Will need to include expansion in our next studies. #atkinsrealis #citysimulator.

The Importance of Secure Load-Bearing Connections in Bridge Design 🌉 In bridge engineering, a secure load-bearing connection is not just a technical detail - it's a critical component that ensures the safety, stability, and longevity of the entire structure. 🚧 Without a proper force-transmitting connection between bridge bearings and the supporting structures, the consequences can be severe. Uneven load distribution, unwanted vibrations, and structural damage are just a few of the risks that can compromise the bridge's integrity. How can a force-fit connection be assured 💪 By using the right suitable gap compensation, it can ensure that forces are transmitted efficiently and evenly, we can prevent material fatigue, control movement, and reduce the risk of damage from environmental factors. Ultimately, this leads to longer-lasting bridges, fewer maintenance issues, and, most importantly, safer infrastructure for everyone. How exactly do you ensure a force-fit connection? Or are partial load peaks okay?   #BridgeEngineering #BridgeDesign #GapCompensation

🏗𝐔𝐧𝐝𝐞𝐫𝐬𝐭𝐚𝐧𝐝𝐢𝐧𝐠 𝐋𝐨𝐚𝐝 𝐕𝐚𝐫𝐢𝐚𝐭𝐢𝐨𝐧𝐬: 𝐀𝐒𝐂𝐄 7-22 𝐈𝐧𝐬𝐢𝐠𝐡𝐭𝐬🏗 1️⃣ 𝑳𝒐𝒂𝒅 𝑭𝒂𝒄𝒕𝒐𝒓𝒔 𝒇𝒐𝒓 𝑫𝒆𝒂𝒅 𝒂𝒏𝒅 𝑳𝒊𝒗𝒆 𝑳𝒐𝒂𝒅𝒔: ASCE 7-22 acknowledges that dead loads, being relatively permanent, are more accurately estimated compared to live loads. Consequently, the load factors for dead loads are smaller as their magnitudes are more reliably known during design. 2️⃣ 𝑫𝒖𝒓𝒂𝒕𝒊𝒐𝒏 𝒂𝒏𝒅 𝑴𝒂𝒈𝒏𝒊𝒕𝒖𝒅𝒆 𝒐𝒇 𝑳𝒐𝒂𝒅𝒔: Loads that persist for longer durations, such as dead loads, exhibit less variability in magnitude. Conversely, transient loads like wind loads, being applied briefly, tend to have larger variations in their magnitudes. 3️⃣ 𝑾𝒊𝒏𝒅 𝑳𝒐𝒂𝒅 𝑷𝒓𝒐𝒃𝒂𝒃𝒊𝒍𝒊𝒕𝒚 𝒂𝒏𝒅 𝑪𝒐𝒎𝒃𝒊𝒏𝒂𝒕𝒊𝒐𝒏: ASCE 7-22 accounts for wind loads by considering approximately a 15% probability of exceedance within a 50-year period. This maximum wind load is combined with various other loads, whose magnitudes are estimated at the time of this particular maximum load event. 4️⃣ 𝑼𝒑𝒍𝒊𝒇𝒕 𝑪𝒐𝒏𝒔𝒊𝒅𝒆𝒓𝒂𝒕𝒊𝒐𝒏𝒔 𝒊𝒏 𝑳𝒐𝒂𝒅 𝑪𝒐𝒎𝒃𝒊𝒏𝒂𝒕𝒊𝒐𝒏𝒔 5 𝒂𝒏𝒅 7: Load combinations 5 and 7 within ASCE 7-22 are specifically incorporated to address uplift scenarios. These combinations factor in cases where tension forces develop due to overturning moments. This scenario often governs the design considerations for structures like steel warehouses and tall buildings, particularly when subjected to high lateral loads. Additionally, in these combinations, a 10% reduction in dead loads is applied to accommodate situations where they might have been overestimated. Like the post? I would appreciate if you could like, comment or share this content. With your help, the information will be available for even more engineers. #ASCE7 #structuralengineering #LoadCombinations #DeadLoads #LiveLoads #WindLoadProbability #UpliftConsiderations #steelstructures #TallBuildingsDesign #EngineeringCodes

Have a look at the dynamics of structure analysis in joints.

Ground Grid Resistance: It refers to the resistance between the grounding system (ground grid) and the earth. This resistance is crucial for ensuring the safety of personnel and the proper operation of electrical systems during fault conditions. Objectives of Ground Grid Design Safety: The primary goal is to ensure that the touch and step voltages are within safe limits to protect personnel. Performance: To provide a low-resistance path for fault currents to flow into the earth, thereby minimizing the potential rise and ensuring proper operation of protective devices. Key Factors Affecting Ground Grid Resistance are as follows: Soil Resistivity: This is the most significant factor. Lower soil resistivity results in lower ground grid resistance. Grid Geometry: The design and layout of the grounding grid, including the number, spacing, and depth of conductors. Grid Size: Larger grids generally have lower resistance. Number and Placement of Ground Rods: Additional rods can lower the overall resistance.

Bridge dampers are crucial components in bridge engineering for several reasons: 1. Vibration Reduction: They help reduce the vibrations caused by various factors such as wind, traffic loads, and seismic events. This is important because excessive vibrations can lead to structural fatigue and damage over time. 2. Improved Comfort and Safety:By reducing vibrations, bridge dampers improve the comfort and safety of vehicles and pedestrians using the bridge. Reduced vibrations can also enhance the lifespan of bridge components. 3. Seismic Resilience: In areas prone to earthquakes, bridge dampers play a significant role in enhancing the seismic resilience of bridges. They can absorb and dissipate energy during seismic events, helping to prevent catastrophic failure. 4. Cost Savings: While installing bridge dampers adds to the initial construction cost, they can lead to long-term cost savings by extending the lifespan of the bridge and reducing maintenance and repair expenses caused by excessive vibrations. Overall, bridge dampers are essential for ensuring the structural integrity, safety, and longevity of bridges, especially in areas with high traffic or seismic activity. #civilengineering #transportaionengineer #civilconstruction #realestate #designengineer

The little known incident that changed the #aerodynamics design of buildings. In Nov. 1965, 3 out of 8 cooling towers at Ferrybridge Power Stations collapsed in gales of 85 mph. The towers were 375ft high and they were constructed closer together than usual. The enquiry found several contributing factors: * Basic wind speed was used as the average over a 1-minute period, whereas the structures were susceptible to much shorter gusts. * The grouped shape of the cooling towers allowed winds to be funneling into tower to create a #vortex. A phenomenon not fully known and considered in design codes at the time. * Wind loading were underestimated due to lower safety margin. Design wind pressures at the tops of the towers were 19% lower than they should have been. The #collapse ensured the early adoption of a limit state code of the practice in the UK, resulting in a completely new approach to design and higher safety wind loading factor. Source: Failures in Concrete Strucutres Book, CRC Press

#structuredesign #structuralengineering As the wind blows against a building, the resulting force acting on the elevations is called the ‘wind load’. Wind load is essentially the wind pressure, in pounds per square foot, exerted on a building. Due to wind load, there can be: -> Uplift wind load (affects roof/horizontal structures). -> shear wind load (horizontal pressure that can damage walls). ->lateral wind load (can cause foundational issues). These Physical mechanisms due to wind loads can be seen in the video attached. The wind load will vary according to the: •Location. •terrain. •height of building. •size and shape of the building. •exposure. The building’s structural design must absorb wind forces safely and efficiently and transfer them to the foundations in order to avoid structural collapse. Source: Structures with Prof . H (https://lnkd.in/dXYGpMvD)

What are thermal bridges, and why are they important? Whether designing a new build or working on energy-efficient upgrades to an existing property, it is critical to pay close attention to the details at junctions and have thermal bridges modelled to limit the risk of heat losses, condensation and mould. Our blog explores the importance of modeling thermal bridges. By understanding factors like Psi and fRsi values, we can mitigate heat loss and mould risks effectively. We also provide a real-life example showcasing how thermal bridge modeling can make a tangible difference in energy efficiency. #EnergyEfficiency #ThermalBridges #Sustainability

Vibration on UK transport networks presents significant challenges for asset owners and maintainers. Geobear uses its engineering designs to reduce vibration affecting structures adjacent to busy roads or railways. This case study outlines how our low-carbon solutions reduced movement on a rocking slab and vibrations affecting houses. #vibrationcontrol #highways #structuralmovement #groundcontrol Vibration control and reduction on rocking slabs https://lnkd.in/d2uh9J_R