The BLWTL offers a range of additional wind consulting services which can complement or contribute to more typical testing programmes.
Wind-Induced Cable Vibration Analysis
Cable-supported structures require specialized assessment to safeguard against wind-induced cable vibration. These critical components are susceptible to several complex excitation mechanisms, including vortex shedding, galloping (often exacerbated by rain or ice accretion), and external excitation resulting from deck or pylon movement. Failure to accurately model and address these phenomena can lead to user discomfort, premature fatigue, and long-term structural issues. Our service provides a comprehensive numerical analytical and assessment of the potential for vibration across all critical wind and weather conditions.
Our study evaluates the likelihood of cable motion, comparing the results against stringent industry-standard criteria. We assess the risks posed by various mechanisms, utilizing analytical methods to predict instability and large-amplitude motions, providing target damping levels in each cable required to eliminate the risk of these motions.
Example Response Amplitude Prediction from Wind-Induced External Cable Excitation
Vehicle Overturning Analysis
We provide the critical data required to establish safe operating limits for highway and bridge structures, particularly long-span bridges exposed to high winds. This specialized study utilizes static wind tunnel tests employing scale models of representative vehicles mounted to the structure’s deck section model to evaluate rollover scenarios. During testing, the scale-model vehicles are mounted to a sensitive force balance to measure static aerodynamic force coefficients across the full 360-degree range of wind directions. This measured data is then input into a numerical analysis to determine the required wind speed for vehicle rollover, considering the vehicle’s speed and direction of travel. By quantifying the expected rollover wind speeds for the structure, we deliver the definitive information necessary for setting informed speed limits, designing appropriate warning systems, and ensuring public safety under high-wind conditions.
Model Truck Mounted to Bridge Deck
Fatigue and Load Cycle Estimation
We provide the essential dynamic responses required for a robust structural fatigue analysis. We combine the project’s site-specific wind climate with the dynamic properties of your structure to precisely estimate the magnitude and frequency of large-load-cycle wind-induced oscillations. By quantifying these long-term fatigue-inducing responses, we deliver the necessary inputs to ensure the structure’s long-term durability and support a comprehensive fatigue assessment of the design.
We offer these advanced analyses not only for the primary structure but also for secondary components and non-structural elements, such as light posts.
Example Maximum Amplitudes of Wind-Induced Responses for Fatigue Analysis of a Structure
Damping Systems
Flexible structures such as high-rise towers, industrial chimneys, observation decks, and long-span bridge cables can experience detrimental vibrations under normal and extreme winds. We consult on the use of tuned damping systems for effectively mitigating these excessive wind-induced motions.
We provide expert guidance in selecting, sizing, and optimizing the appropriate damping system including Tuned Mass Dampers (TMD) and Tuned Liquid Dampers (TLD). We analyze the structure’s unique dynamic properties to precisely tune these systems to counteract specific vibrational frequencies. This precision maximizes motion reduction, thereby improving occupant comfort, preserving structural integrity, and extending the service life of the structure.
Plan Drawing of a Tuned Liquid Damper
Environmental Solutions
Environmental solutions stem from climatological studies of wind, snow, rain, and other meteorological variables, providing vital information required for robust structural design. Snow and ice loads exhibit significant variability, often differing markedly from standard code values due to geographic climate, roof characteristics, and the influence of nearby buildings. We utilize both physical model studies and advanced numerical methods to evaluate how complex factors like wind, temperature, and heat loss impact the accumulation, redistribution, and sliding hazard of snow and ice, thereby ensuring safe, code-compliant environmental designs for every project.
Wind Tunnel Snow Distribution Testing
Connect with the Boundary Layer Wind Tunnel Laboratory to discuss your project’s unique design and challenges.