The Challenge
Capitol Metro was planning to use non-FRA compliant DMUs as a cost-effective method of starting commuter rail service in the Austin area. This type of vehicle was new to the US market, and there was no existing body of noise and vibration data for use in environmental studies.
The Strategy
HMMH conducted a noise and vibration study and took new measurements to complete the analysis. Our work included:
DMU Vehicle Measurements from the Ottawa Transit Authority
The Ottawa Transit Authority (OTA) had one of only two active DMU operations in North America. HMMH's extensive contacts in the transit industry allowed us to coordinate the measurements with the OTA in order to obtain the information required for the analysis.
Comparison of Vehicle Types
In addition to the environmental analysis of the DMUs, HMMH:
- Provided a summary of the noise and vibration levels of several types of transit vehicles from our extensive data set
- Conducted an analysis to show the relative impacts of each type of vehicle in order to assist Capitol Metro in their planning process
- Quantified the noise and vibration benefits of the DMUs, as compared with traditional commuter rail and LRT
The Solution
Data from measurements on operating vehicles showed significantly fewer impacts than a previous assessment based on assumed noise and vibration levels for these vehicles.
