software maintenance

Wall Design

Wall Design is one of the most popular of SoundPLAN modules, and another of SoundPLAN's modules that sets the standard.

Wall Design consists of two parts; one part is integrated into the calculation core and prepares the data which the on-line part uses to dimension and optimize noise control barriers. In order for Wall Design to work, a single barrier is marked as the barrier to be iterated in height. SoundPLAN requires this barrier be stored in a Geo-File of its own. This makes it easier to swap the raw barrier with an already dimensioned one later.

The only information needed for the pre-calculation is the iteration step height and the total number of steps. The calculation iterates each section of the noise barrier for the predefined number of steps, and records the reductions for each step. This later becomes the basis of the on-line selection of the noise barrier. Because SoundPLAN objects can change at any coordinate, it is possible to have a barrier of several hundred coordinates with the height of the noise barrier changing at each coordinate. Other software products claim an on-line optimization, but they only deliver a noise barrier with a constant height from beginning to end.

The on-line barrier optimization searches for the noise barrier with the smallest cost or for the projection area that will reduce the noise level for all receivers so it is below the required noise limit for that particular receiver. The area usage where the receiver is located determines the noise limit. As part of the optimization, Wall Design presents the total length, total projection area, and the total cost. The cost matrix for different heights of the barrier is user defined and involves the land acquisition, building costs at various heights, as well as maintenance costs. The program analyses both barriers and earthen berms.

After the automatic dimensioning, the designer should adjust the wall so it is aestheticly pleasing as well as technically accurate. Do this by increasing and decreasing the wall height of individual sections of the wall. The resulting noise levels can be viewed instantaneously under "Receiver Location." The shape of the wall can be presented as a projection or as a 3D solid model.

Unfortunately there are cases where noise levels are so high it is impossible to reduce the noise to the required limit. For cases like these, it is wise to calculate the barrier for a very low noise limit and determine the shape of the barrier with the Dimensioning History.

Wall Design records each step of the optimization. This optimization history is seen in the screenshot above. The form of these diagrams is basically the same for each optimization. At first, the wall has to increase in height until it intercepts the line of sight. This section can be very short. The noise levels in the next section are significantly reduced for each additional square meter of extra wall. In the last section, the reduction continues until the curve is horizontal and has reached the saturation of the screening. Clicking on the diagram in a position where the ratio of cost versus performance is still favorable instantly displays the wall representing this location. If the tab "Receiver Locations" is activated, the program shows the expected noise levels for each of the receivers.

After selecting the desired noise protection wall, the last steps are the same, customizing the appearance of the wall and storing it as a new GeoFile so that other calculations have access to this wall without extra handwork.

Last modification: 15 January 2004