FREEWAY RESPONSIVE SYSTEM IH 10 TxDOT Houston Steve Chiu, TxDOT Roma Stevens, P.E., PTOE, TTI Oct 14, 2015
FREEWAY MOBILITY Address Congestion
AIM Help alleviate freeway traffic through signalized intersections when freeway traffic level of service is deteriorating. 3
ISSUES Where to displace freeway traffic when freeway traffic is no longer free flowing. Due to : incident, constructions, and various things that slowdown free flowing condition. 4
CONCEPT Sensor Monitor Freeway Condition Output info to intersections Intersections respond 5
DESIGN Sensors monitor freeway conditions Sensors output contact when conditions met Sending contact information to intersections Intersections receive information Intersections react to the input 6
DESIGN Using the Wavetronix Radar sensor to monitor both direction of freeway. Monitoring freeway vehicle speed, volume, or occupancy. Using contact closure radio to send contact signals to traffic signal cabinets when preset freeway condition threshold is reached. Using two contact inputs to generate 3 timing plans. Ex: on-off plan 1 (inbound condition), off-on plan 2 (outbound condition), and on-on plan 3 (both). 7
DESIGN 8
DESIGN IH 10 - limits from west of SH 6 to Mason 9
EQUIPMENT Wavetronix HD Sensor with Criteria Signaling feature Click! 513 contact closure Intuicom 900 MHz radio with I/O contact closure Econolite ASC 3 traffic signal controller 10
INSTALLATION Adapt existing freeway sensors Installed additional equipment for responsive system-click 513! and Click 300! Install antennas and I/O communication equipment at sensor locations and at intersections. 11
INSTALLATION Sensors 12
INSTALLATION Sensors 13
INSTALLATION I/O or contact closure radio 14
INSTALLATION Intersection antenna 15
INSTALLATION Signal Cabinet 16
INSTALLATION Contact Closure Inputs - Test A&B West Bound Test A Input East Bound Test B Input 17
INSTALLATION Attach Logic Ground 18
SETUP AND OPERATION Sensor setup how many lanes and directions Contact closure interval criteria setup - speed, volume and/or occupancy. Program radio for contact closure inputs and outputs at sensor location and traffic signal cabinet. Connect the radio contact closure outputs at the intersection to the designated input terminals. 19
SETUP AND OPERATION 20
SETUP AND OPERATION 21
SETUP AND OPERATION 22
TRAFFIC PATTERN PM Traffic 23
FREEWAY INCIDENT 24
SETUP AND OPERATION Radio setup allows all intersections to receive all 3 sensor outputs 25
DATA COLLECTION All the data collection is done by the HD sensor at 30 seconds interval. Click 513 pulled data every 5 seconds. When all criteria are met then contact closure closed. 26
CONTROLLER LOGIC STATEMENT Inbound Statement Outbound Statement Both Statement IF: IF CIB CODE ON 160 AND CIB CODE OFF 161 THEN: SET ACTION PLAN ON 10 ELSE: IF: IF CIB CODE OFF 160 AND CIB CODE ON 161 THEN: SET ACTION PLAN ON 11 ELSE: IF: IF CIB CODE ON160 AND CIB CODE ON161 THEN: SET ACTION PLAN ON12 ELSE: Test A = CIB CODE 160 Test B = CIB CODE 161 27
CONTROLLER ACTION PLAN Action plan 10- Max 3 time is Checked for Phase 8 (West Bound Frontage Road) 28
RESULTS 29
DATA (01/16/2015 PM) Alarm Log For Barker Cypress intersection 30
DATA (02/12/15 AM) Alarm Log For Green House intersection 31
INCIDENT ON 05/08/2015 IH 10 WITH FREEWAY CLOSED 32
Freeway Condition Info\EFPlayer.exe 20150212-0730_20150212-0800(greenhouse).avr (AM) 20150116-1600_20150116-1800(correct data).avr (PM) 33
OTHER USES Monitor exit ramp condition. When the exit ramp traffic is backup, the sensor can trigger a low priority preemption, a TSP (Transit Signal Priority) input or an alternative timing plan to clear the exit ramp traffic. With Peer to Peer feature, adjacent intersection can also react to the new action plan. 34
COST HD SENSOR- 1 POWER SUPPLY- 1 CLICK! 513-1 I/O RADIO- 2 ANTENNA- 2 Total : approx. $11,000.00/ location Additional intersection : $3500.00 35
BENEFITS What are the benefits? Can we quantify? What happens to cross-street traffic? Is it always the solution? 36
BENEFITS CALCULATIONS Install more sensors to collect VERY DETAILED travel time data and queue lengths More costs to document the benefits Micro-simulation using VISSIM to document the benefits Less expensive Collected exit and entry ramp volumes Collected turning movement counts at intersections Timing plans Mainlane volumes from Wavetronics Travel time data from travel map for model calibration 37
SIMULATION PROCESS Developed a VISSIM model Freeway segment between SH 6 and Mason Road Frontage between SH 6 and Greenhouse Road focus on Barker Cypress, WB direction and PM Peak Period Going outbound, Barker Cypress signal is the first TxDOT maintained signal for changing timing plans Barker Cypress Entry from Barker Cypress Exit to Greenhouse Road WB Exit to Barker Cypress 38
Typical Volumes in Study Segment 1344 1588 2146 4106 1526 7765 720 297 39
MEASURES OF EFFECTIVENESS PM Peak Hour Throughput Freeway throughput Cross street and EB Frontage throughput WB Frontage road throughput Delay Delay for freeway Delay for WB frontage approach Delay for SB approach Overall Intersection Delay 40
MEASURES OF EFFECTIVENESS PM Peak Hour (4:00 to 5:00) Throughput Freeway Increased by 500 vph Cross street and EB Frontage Decreased by 115 vph WB Frontage Increased by 380 vph Delay WB Freeway 64 Veh-hrs WB frontage approach 130 s/veh, 86 Veh-hrs SB approach Increased by 62 s/veh, 13 veh-hrs Total Intersection 68 veh-hrs 41
User Benefits of Delay Savings Value of Time - $21.90 per hour Delay savings for one hour of PM peak = 132 vehicle hours Delay savings for PM peak = 2*132 =264 vehicle hours Monetary value of delay savings/weekday = 264*21.90 = $5,780 System cost per intersection $11,000 Breakeven period 2 days PM peak 42
CONCLUSION Using frontage road to alleviate freeway traffic during less desirable level of service can be an alternative solution to freeway traffic congestion. 43
GOING FORWARD Do a sensitivity analysis to identify when and where it is most beneficial What happens if intersection is fully saturated Closely spaced intersections along X-street Off-peak incident condition Develop a guidance document Time of Day triggering 44
Questions??? 45
Contact Steve Chiu Texas Department of Transportation Houston District Steve.Chiu@txdot.gov P: (713) 802-5936 Roma Stevens, P.E., PTOE Associate Research Engineer Texas A&M Transportation Institute romastevens@tamu.edu P: (713) 613-9216 46