A Pooled Fund Study project for the Smart Work Zone Deployment Initiative (SWZDI) designed a support system for a low-cost QWS.
Nationwide, United States
Development of a Low-Cost Work Zone Queue Warning System
Summary Information
The objective of this project was to design a low-cost modular queue warning system (QWS). The system was designed with multiple roadside detection units, and networked communication systems attached to portable roadside static signs. The signs are intended for deployment as far upstream as necessary to provide ample driver notification in situations with high, medium, and low traffic demand.
The final low cost design selected by researchers would cost a fraction of the conventional QWS based on portable changeable message signs. After considering several designs, the final design uses a non-proprietary support system crash tested by the Texas A&M Transportation Institute (TTI), using sign sizes restricted to a maximum of 36 x 36 inches.
Before developing a low-cost QWS, an investment in funding for crash testing is strongly recommended to verify that signage support structures with QWS traffic sensors and communications hardware attached are crashworthy, in accordance with the American Association of State Highway and Transportation Officials (AASHTO) Manual for Assessing Safety Hardware (MASH).
While the project's design builds upon an approved support system, the QWS has not been field tested on highways since the complete assembly with additional hardware has not been tested for MASH approval.
The project also encountered a lack of compatible highway locations where equipment could alternatively be located in a barrier-protected area or outside a clear zone for field testing.
