Crossing
The majority of standards for road noise do not offer to model road crossings controlled by traffic lights.
A correction for traffic lights will only be considered with the selected road noise standard or procedure requiring this. Otherwise, even an active object „Crossing w/ Traffic Lights“ has no effect. Details are given in the table below.
| Standard/Procedure | Object „crossing“ with effect yes=1/no=0 | Calculation according to ... |
| RLS-90 | 1 | RLS-90 RLS-1990 |
| RLS-19 | 1 | RLS-19 |
| RVS 4.02 | 0 | - |
| STL 86 | 1 | Swiss „Guideline for Road Noise“ BAFU37-2006 |
| DIN 18005 (1987) | 0 | - |
| Nordic Pred. Method | 0 | - |
| NMPB-Routes-96 | 0 | - |
| NMPB-Routes-08 | 0 | - |
| CNOSSOS-EU | 1 | EU-2015, EU-2021 or country specific interpretation |
| CRTN | 0 | - |
| TNM | 0 | - |
| Czech Method | 1 | RLS-90 |
| SonRoad | 0 | - |
| SonROAD18 | 0 | - |
| HJ 2.4 (2009 / 2021), HJ 1358 (2024) *) | 1 | RLS-90 |
*) only described in the HJ 2.4 (2009) standard, but available for all HJ standards in CadnaA
Calculation according to RLS-90
In RLS-90, the location of the object „Crossing“ in the model does not comply with its physical location, but is the imaginary intersection point of the respective emission lines (which is a hatched line, by default).
In the model, the object „Crossing“ is located at the imaginary intersection point/s of the respective emission lines
Options
Name, Memo-Window, ID, ObjectTree, Memo, Master
see Dialog Options Name, ID, INFO, ObjectTree, Master in the manual "Introduction to CadnaA"
Light is active
When allocating a traffic light to a crossing or junction, the penalty according to RLS-90, section 4.2, table 2, is added to the receiver level automatically taking into account at what time, day, evening or night, the traffic light is active.
| distance d of the receiver from the closest intersection of emission lines | correction K (dB) |
|---|---|
| <= 40 m | 3 |
| 40 < d <= 70 m | 2 |
| 70 < d <= 100 m | 1 |
| > 100 m | 0 |
The correction K is applied only once (at multiple crossings with traffic lights).
The check boxes enable to specify traffic light’s activity separately for daytime, evening and night-time. In the graphics, an active traffic light is indicated by a cross within the square.
Crossing is Roundabout
If this option is enabled, a roundabout (instead of a crossing with traffic lights) is taken into account in the calculation, if this is specified by the calculation method (e.g. CNOSSOS-EU, RLS-19).
Associated Roads, find automatically
Any road lying within a distance to the traffic light’s position smaller / equal the distance entered at „Search radius“, it will be allocated to this crossing in the calculation.
Search Radius
Search radius to be used to allocate nearby roads. Default value: 20m.
Update
Manual search of roads within the search radius and display in the “ Manually” section. If the “automatic” option is selected, this process takes place before each calculation.
To allocate a road to a crossing with traffic lights, enter at least a single active receiver and start the calculation by clicking the pocket calculator icon.
Note
In RLS-90 it is not explicitly specified how many and which roads in the vicinity of a traffic light receive the correction K. The procedure applied in CadnaA prevents from including other roads in the vicinity (e.g. a highway nearby). The automatic assignment is, therefore, a compromise not to apply the correction to too many roads.
Associated Roads, assign manually
When selecting this option the respective roads can be assigned manually. Select via the button „Insert“ the name of the roads to be assigned from the table Road.
Note
Roads outside the search radius always require to be assigned manually in order to receive the correction. When roads nearby a traffic light are broken into pieces (e.g. with different speed limits) a manual assignment of all sections in the distance range <search radius> to 100 m is required.
Example
Road crossing with traffic lights: Grid showing the correction with limiting distances according to RLS-90
Calculation according to Swiss „Guideline for Road Noise“
The correction according to Swiss „Guideline for Road Noise, advice paper No. 0637“ BAFU37-2006 is considered only if the road noise standards STL86+ or SonRoad are selected and the object „Crossing“ is used.
| distance d of the receiver from the closest intersection of emission lines | correction (dB) |
|---|---|
| < 25 m | 2 |
| 25 <= d < 50 m | 1 |
| d >= 50 m | 0 |
Furthermore, all remarks as given for RLS-90 hold, especially, with the option „Find Automatically“ being activated (default setting) the search radius to the traffic light’s position is used to decide whether a road is being listed in „Associated Roads“ or not.
Again, the option „Crossing is Roundabout“ does not apply, see CNOSSOS-EU below.
Example
Road crossing with traffic lights: Grid showing the correction with limiting distances according to the Swiss „Guideline for Road Noise“
Calculation according to CNOSSOS-EU
In CNOSSOS-EU, the effect of the acceleration and deceleration of vehicles before and after crossings with traffic lights and at roundabouts is considered by correcting coefficients CR,m,k and CP,m,k depending on vehicle category and for crossings and roundabouts separately (for values see CNOSSOS-EU EU-2015). Both coefficients are not frequency dependent and are attributed to all octave bands equally.
The correction terms for rolling noise, ΔLWR,acc,m,k, and for propulsion noise, ΔLWP,acc,m,k, are linear functions of the distance x (in m) of the point sources - resulting from the segmentation of the road/s - to the nearest intersection of the respective source line with another source line:
\(\Delta L_{WR,acc,m,k}=C_{R,m,k}*max(1-\frac{|x|}{100}; 0) dB\)
\(\Delta L_{WP,acc,m,k}=C_{P,m,k}*max(1-\frac{|x|}{100}; 0) dB\)
The coefficients CR,m,k and CP,m,k depend on the kind of junction k (k = 1 for a crossing with traffic lights; k = 2 for a roundabout) and are given for each vehicle category. The correction includes the effect of change in speed when approaching or moving away from a crossing or a roundabout.
Note that the correction becomes 0 dB at distances of 100 m and larger: \(|x|\geq100m: \Delta L_{WR,acc,m,k} = \Delta L_{WP,acc,m,k} = 0 dB\)
Crossing is Roundabout
Activate this option to mark a roundabout. In this case the corrections for k=2 are applied.
Note
In opposite to RLS-90 and SN 640 578, CNOSSOS-EU considers the correction for crossings with traffic lights and roundabouts on the source-side. This, however, may lead to different results depending on the raster factor applied (see Partition Tab).
Example
Road crossing with a single traffic light according to CNOSSOS-EU:
All rays extending from a source location at a maximum distance of 100 m from the traffic light receive a correction (red rays) while rays extending from more than 100 m distance do not receive the correction (gray rays).
Note that the correction does NOT depend whether the receiver or grid point is situated closer than 100 m distance from the traffic light‘s location or not.
Calculation acc. to HJ 2.4 (2009/2021)
Please note, that wile HJ 2.4 2009 HJ24-2009 defines the calculation of crossings, it is not included in HJ 2.4 2021 HJ24-2021. When calculating according to version 2021, an object „crossing“ is considered as described in version 2009.