SIDRA INTERSECTION 11
INTERSECTION DESIGN
Every Intersection,One Environment

Signalised, roundabout, sign-controlled, interchange, and innovative designs — analysed with consistent lane-level methodology.

Geometry ThatShapes Capacity

Short lanes, slip lanes, U-turns, continuous lanes — the lane configurations that drive real-world performance, modelled explicitly.

Every TransportUser, Not Just Cars

Twelve Movement Classes with distinct vehicle characteristics — from light vehicles and buses to trams and user-defined modes.

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SIDRA INTERSECTION

One tool for everysignalised intersection.roundabout.interchange.street & network.

A lane-based micro-analytical tool built on more than 50 years of continuous traffic research. Design, assess and compare every facility type in a single analytical environment — with results reported at the individual lane level.

Every facility type in one environment — from signalised intersections to freeway segments.

Signalised intersections
Fixed-Time and Actuated control, up to 8 legs, variable phasing, multiple phase sequences, Turn On Red, slip lane signal treatment, permitted-protected turns
Roundabouts
Unsignalised, with metering signals, and fully signalised. Five capacity model options including SIDRA Standard, HCM Edition 6, HCM 6 Extended, and HCM 2010
Sign-controlled intersections
Two-Way Stop, Two-Way Give-Way/Yield, All-Way Stop. One of the few tools that models Give-Way/Yield
Interchanges
Single-point, diamond (signalised, roundabout, sign-controlled), and Diverging Diamond Interchanges (DDI)
Innovative designs
Pre-built templates for DDI, RCUT, CFI, DLT, MUT, P-Turn, and Divergabout
Pedestrian crossings
Signalised and unsignalised (zebra), midblock, staged, slip lane and diagonal crossings
Freeway segments
Merge/diverge segments, basic segments, arterial midblock, and continuous lanes

SIDRA INTERSECTION models the lane configurations that shape real-world capacity and performance. Intersections with up to 8 legs are supported.

Short lanes
Turn bays, lanes with upstream parking, exit-side lane drops. The short lane model handles complex multiple short lane combinations where overflow blocks adjacent full-length lanes.
Slip/bypass lanes
Shared, exclusive with yield control, and continuous. Signal treatment includes two green periods for slip lane movements.
Exit short lanes with merging
Priority Merge and Zipper Merge operations at any intersection type, with effect on approach lane use.
U-Turns
Modelled at all Site types including U-Turn before intersection at signalised and unsignalised Sites.
Continuous lanes
Uninterrupted flow modelling with detailed midblock performance estimates.
Turn bans and contra-flow lanes
Movement restrictions and opposing-direction lane configurations.

This geometric detail is what enables the lane-based capacity, queuing and performance calculations that distinguish SIDRA from tools that model at the lane-group or approach level.

Twelve Movement Classes — each with its own vehicle characteristics. Not PCE conversions. Actual queue space, speed, acceleration and mass.

Light Vehicles
Cars, SUVs, vans
Heavy Vehicles
Rigid trucks, trailers
Buses
Priority lanes & phases
Bicycles
Dedicated lanes & phases
Large Trucks
B-doubles, road trains
Light Rail / Trams
Explicit tram modelling

Each Movement Class retains its own characteristics throughout the analysis. Capacity, delay, queue length, travel time, stop rate, fuel consumption, emissions and operating cost are all calculated and reported separately. Bus priority lanes and signal phases, dedicated bicycle lanes and phases, and tram/light rail movements are modelled explicitly.

Pedestrian modelling in SIDRA INTERSECTION goes well beyond pedestrian minimum walk and clearance time effects on signal timing.

Pedestrian movements and signal characteristics
As explicit input
Effect of pedestrians on capacity
Of vehicle movements at signalised and unsignalised intersections and midblock
Holding a red arrow
For pedestrian protection at signalised intersections
Pedestrian actuation effects
On signal timing
Pedestrian delay and queue estimates
At signalised intersections
Zebra (unsignalised) crossings
On slip lanes and at midblock locations
Staged, slip lane and diagonal crossings
At signalised intersections
Walk time extension
For accessible pedestrian phases

Optimum signal timings can be determined for minimum person delay — not just minimum vehicle delay.

Country-specific setups with default parameters based on established research. Standard and US HCM setups (Customary and Metric) included.

Roundabout capacity
Environment Factor and Model Calibration Factor
Gap-acceptance models
Critical gap and follow-up headway parameters
Signalised intersections
Saturation flow rates and adjustment factors
Movement Class parameters
Speed, acceleration, queue space and mass
Emissions modelling
Fuel consumption calibrated for modern fleets
Parameter Sensitivity
Systematic testing of the effect of variations in key parameters. Identify which inputs have the greatest impact on results.
Design Life analysis
Assessment over traffic growth horizons. Model how intersection performance changes as demand increases over 5, 10, 20 year timeframes.
Flow Scale analysis
Explore demand variations and identify capacity thresholds. Understand at what traffic levels your intersection reaches its performance limits.

Analytical models run in seconds rather than minutes or hours. Analyse many design alternatives and optimise across multiple dimensions.

Intersection geometry
Lanes, widths, short lanes, slip lanes, roundabout diameter & entry geometry
Signal phasing
Phase sequences, variable phasing, permitted-protected configurations
Signal timing
Optimum cycle time, green splits, target degrees of saturation
Alternative designs
Compare signalised, roundabout, sign-controlled & innovative alternatives

Results are available at Lane, Movement, Approach, Site, Network and Route levels for 10 performance metrics including Level of Service, Delay, Queue length, Back of queue, Stop rate, Travel time, Speed, Fuel consumption, Emissions and Operating cost.

Rapid setup and calibration with pre-built templates and country-specific Software Setups.

18 Roundabout Templates
Pre-configured roundabout geometries for rapid site creation
7 Network Templates
Multi-site network configurations ready for analysis
40 Country Setups
Calibrated defaults for country-specific conditions

The Map Extract tool creates new Sites from map data. Country-specific Software Setups provide calibrated defaults. Parameter Sensitivity analysis supports systematic testing of key parameters.

Every facility type in one environment

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Signalised intersectionsRoundaboutsSign-controlled intersectionsInterchangesInnovative designsPedestrian crossingsFreeway segments

Fixed-Time and Actuated control, up to 8 legs, variable phasing, multiple phase sequences, Turn On Red, slip lane signal treatment, permitted-protected turns

Unsignalised, with metering signals, and fully signalised. Five capacity model options including SIDRA Standard, HCM Edition 6, HCM 6 Extended, and HCM 2010

Two-Way Stop, Two-Way Give-Way/Yield, All-Way Stop. One of the few tools that models Give-Way/Yield

Single-point, diamond (signalised, roundabout, sign-controlled), and Diverging Diamond Interchanges (DDI)

Pre-built templates for DDI, RCUT, CFI, DLT, MUT, P-Turn, and Divergabout

Signalised and unsignalised (zebra), midblock, staged, slip lane and diagonal crossings

Merge/diverge segments, basic segments, arterial midblock, and continuous lanes

Lane-level geometric detail

SIDRA INTERSECTION models the lane configurations that shape real-world capacity and performance. Each approach can include:

Short lanes

turn bays, lanes with upstream parking, exit-side lane drops. The short lane model handles complex multiple short lane combinations where overflow blocks adjacent full-length lanes.

  • Slip/bypass lanes

    shared, exclusive with yield control, and continuous. Signal treatment includes two green periods for slip lane movements.

  • Exit short lanes with merging

    Priority Merge and Zipper Merge operations at any intersection type, with effect on approach lane use.

  • U-Turns

    modelled at all Site types including U-Turn before intersection at signalised and unsignalised Sites.

  • Continuous lanes

    uninterrupted flow modelling with detailed midblock performance estimates.

  • Turn bans and contra-flow lanes

    movement restrictions and opposing-direction lane configurations.

Intersections with up to 8 legs are supported, each with one-way or two-way traffic and multi-lane approaches. This geometric detail is what enables the lane-based capacity, queuing and performance calculations that distinguish SIDRA from tools that model at the lane-group or approach level.

Multimodal Analysis

Every transport user, not just cars.buses & transit.bicycles & trams.heavy vehicles.

Twelve Movement Classes — each with its own vehicle characteristics. Not PCE conversions. Actual queue space, speed, acceleration and mass.

Light VehiclesCars, SUVs, vans
Heavy VehiclesRigid trucks, trailers
BusesPriority lanes & phases
BicyclesDedicated lanes & phases
Large TrucksB-doubles, road trains
Light Rail / TramsExplicit tram modelling
12
Classes
+
6
User-defined

Advanced pedestrian modelling

Pedestrian modelling in SIDRA INTERSECTION goes well beyond pedestrian minimum walk and clearance time effects on signal timing.

What SIDRA Models
  • Pedestrian movements and signal characteristicsas explicit input

  • Effect of pedestrians on capacityof vehicle movements at signalised and unsignalised intersections and midblock

  • Holding a red arrowfor pedestrian protection at signalised intersections

  • Pedestrian actuation effectson signal timing

  • Pedestrian delay and queue estimatesat signalised intersections

  • Zebra (unsignalised) crossingson slip lanes and at midblock locations

  • Staged, slip lane and diagonal crossingsat signalised intersections

  • Walk time extensionfor accessible pedestrian phases

The results for persons given in SIDRA output include pedestrians, cyclists and people in vehicles according to occupancy characteristics. Optimum signal timings can be determined for minimum person delaynot just minimum vehicle delay.

Software Setups

Calibrated for local conditions.Standard setups.US HCM setups.

Country-specific setups with default parameters based on established research. Standard and US HCM setups (Customary and Metric) included.

Roundabout capacity
Gap-acceptance models
Signalised intersections
Movement Class parameters
Emissions modelling
Rapid Analysis

Analyse many alternatives, quickly.in seconds.not hours.

Analytical models run in seconds rather than minutes or hours. Analyse many design alternatives and optimise across multiple dimensions.

Intersection geometry
Lanes, widths, short lanes, slip lanes, roundabout diameter & entry geometry
Signal phasing
Phase sequences, variable phasing, permitted-protected configurations
Signal timing
Optimum cycle time, green splits, target degrees of saturation
Alternative designs
Compare signalised, roundabout, sign-controlled & innovative alternatives
Results at every level
Output
Level of ServiceDelayQueue lengthBack of queueStop rateTravel timeSpeedFuel consumptionEmissionsOperating cost
Level
LaneMovementApproachSiteNetworkRoute
10 metrics × 6 levels

Rapid setup and calibration

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Roundabout Templates
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Network Templates
0
Country Setups

The Map Extract tool creates new Sites from map data. Country-specific Software Setups provide calibrated defaults. Parameter Sensitivity analysis supports systematic testing of key parameters.