| 摘要 |
A novel dynamic work zone safety system and method of traffic control for a construction work zone are provided herein. The system includes a first traffic signalling device which is positioned along a roadside immediately upstream of a point where traffic is diverted to a single lane. The first traffic signalling device is defaulted to flash a suitable warning, e.g., "DO NOT PASS" or "MERGE LEFT" or "MERGE RIGHT", thereby to provide a first "NO PASSING" or "MERGE LEFT" or "MER GE RIGHT" zone which is defined by the distance between the first traffic signalling device and the end of the work or construction zone. A second traffic signalling device is positioned alongside a roadside a predetermined distance upstream of the fir st traffic signalling device. The second traffic signalling device defaulted not to fla sh a suitable warning, e. g., "DO NOT PASS" or "MERGE LEFT" or "MERGE RIGHT". However, when activated (by processor-controlled means defined herein) to flash a suitable warning, e.g., "DO NOT PASS" or "MERGE LEFT" or "MERGE RIGHT", the second traffic signalling device provides a second suitable zone, e.g., a "D O NOT PASS" or "MERGE LEFT" or "MERGE RIGHT" zone which is contiguous to the fir st "NO PASSING" or "MERGE LEFT" or "MERGE RIGHT" zone. This lengthens the "NO PASSING" or "MERGE LEFT" or "MERGE RIGHT" zone between the second traffic signalling device and the end of the work or construction zone. A plurality of spaced-apart sensors, preferably non-invasive sensors, is disposed along the roadway both downstream of, and upstream of, the second traffic signalling device. These sensors detect and determine the length of a traffic queue upstream of the first traffic signalling device between the first traffic signalling device and the second traffic signalling device, and provides a signal which is representative of the leng th of the traffic queue. The processor receives the traffic queue signal and generates a first activation signal to activate the second traffic signalling device when the traffic queue reaches a predetermined length. It also generates a first deactivation signa l to deactivate the second traffic signal when the traffic queue is less than the predetermined length. This dynamically increases or decreases the "NO PASSING" or "MERGE LEFT" or "MERGE RIGHT" zone. |
