Forensic Case Studies

Residential Penthouse: 58.3Hz Tonal Transmission

Audible nocturnal vibration in a 20-storey penthouse was traced to a roof-mounted telecom tower. FFT analysis correlated roof signatures with interior radiation, confirming a structure-borne path.

Quarry Plant: Severe Frame Resonance

Excessive vibration on a sieving plant rendered handrails unusable and threatened commercial payment. Combined FEA and EMA identified a mismatch between screen throw and AV mount stiffness.

Gas Compressor: Resolving Resonance via Model Updating

A Roots Systems gas pumping unit failed API 619 vibration audits due to excessive bearing levels. While on-site "trial-and-error" stiffening failed, our **Measured-to-Modeled** approach identified a frame resonance at 47.2Hz.

Using **Ansys FEA** correlated with **Experimental Modal Analysis**, we engineered a structural reinforcement strategy that moved the natural frequency out of the excitation zone.

Precision Plinth Validation: ASML & TEL8 Support

When cleanroom floor construction deviated from original specs, we provided independent verification for vibration-sensitive semiconductor tools. Analysis included 1/3-octave band PSD and heel-drop transient response testing.

Our forensic approach identified **horizontal stiffness asymmetry** linked to non-symmetrical geometry—providing an engineering pathway to optimize plinth performance via FEA and Model Updating.

Breaking the 9-Year Failure Cycle: Mehrer TRZ 700

A high-yield biogas site suffered nearly a decade of chronic gas leaks and pipework fatigue. We identified a "Perfect Storm" where the 28.3 Hz machine frequency was being amplified by the building's concrete floor resonance.

By designing a bespoke **4,200kg inertia base** and re-tuning the VSD "Safe Harbor" logic, we moved the center of gravity and eliminated ground-borne "Beat" interference between dual units.

BPF Mitigation: Mode Shape Manipulation & Axis Decoupling

In this aerospace instrumentation project, a Power Distribution Unit (PDU) constructed from 1.6mm aluminum was failing shaker testing due to resonance at the critical Blade-Pass Frequency (BPF).

Our forensic analysis identified that local mode shapes were coinciding with discrete rotor orders (A1). By implementing topographical stiffening and rotating the component’s sensitive mechanical axis, we decoupled the response from the excitation bandwidth.