What Is a Zipper Merge?
A zipper merge, also known as a late merge, occurs when there is a lane closure within a construction zone. During a zipper merge, vehicles travel down two lanes until they reach the merge point. Then, just like a zipper, vehicles alternate, merging into one lane.
Dynamic Zipper Merge System
Our Dynamic Zipper Merge System is made up of two components, speed sensors, and message signs. Multiple speed sensors are set up along the highway to gather real-time traffic information and patterns. Depending on the current status of traffic, the sensors will tell the message signs how to alert approaching drivers far before they need to begin merging.
In free-flow traffic, message signs will instruct drivers to merge early. In slowed or stopped traffic, message signs will instruct drivers to “Use Both Lanes/To Merge Point.” Using both lanes up until the merging point will speed up the process immensely. When drivers reach the start of the merge, the message signs will read “Merge Here/ Take Turns.”
The zipper-style transition makes for a smooth merging process and greatly reduces traffic backup. Our Dynamic Zipper Merge System eliminates issues that arise from drivers who merge early and drivers who wait until the last second to merge.
Zipper Merge vs. Early Merge
The zipper merge occurs when all merges are executed at the same merge point. In contrast, when drivers see the first sign for a lane closure, their first thought is to merge right then, so they don’t have to worry about getting over later. This “early merge” can actually be counterproductive by extending the length of the queue in the open lane and tightens the traffic prematurely.
When drivers cooperate with the zipper merge, it decreases the length of the traffic back up and provide a safer merging process.
Dynamic Zipper Merge Systems are used on interstate highway work zones. DOTs and construction managers use them for the safety of their workers and to reduce backup times. Typically these systems are only used for long-term construction projects because of how much time it takes to install them. They are most beneficial for lane closures that last over a month.
A zipper merge will make each lane of traffic travel at similar speeds. It is much safer to perform a lane change when all traffic is traveling at the same speed, not to mention much easier. Zipper merges also reduce the total lengths of traffic backups which ultimately reduces traffic time.
Another benefit of the zipper merge is that it makes drivers wait until traffic is slowed, so they execute a safe and simple lane change. One of the best advantages of the zipper merge is that it gives drivers a sense of fairness when having to merge. Everyone knows when it is their turn which keeps road rage levels low and prevents drivers from driving recklessly.
If you are interested in our Dynamic Zipper Merge Systems, we are more than happy to answer your questions and find the best solution for your project. To learn more about our products, visit www.carolinatraffic.com, or contact us today for assistance on your next construction project.