Understanding the difference between Clash Avoidance, Clash Detection and Clash Resolution

Understanding the difference between Clash Avoidance, Clash Detection and Clash Resolution

During the construction of any building irrespective of its size, it is important that there is proper coordination between Architectural, Structural and MEP disciplines involved in the process. Whenever AEC professionals are using Building Information Modelling process it would involve federated models created by these different disciplines which would together reflect the built asset. One of the benefit of adopting BIM is its ability to avoid, detect and resolve clash. Clash Avoidance is an attempt by the BIM team to avoid spatial overlaps and enhance coordination. Clash Detection follows to ensure that incase, even after the best efforts some clashes may have occurred then they are detected. Finally, once the clash is detected the final step is to take proper steps to resolve the clash for a smooth onsite construction process.

In the current blog we will be looking into clash avoidance, clash detection and clash resolution and understanding the difference between all three.

1. Clash Avoidance:

Clash Avoidance is the ideal goal and more like a proactive process. Here the architects, engineers and BIM modelers take steps to ensure that there is spatial coordination and no overlaps take place at either any intra or inter discipline level. It means that right from the project onset different strategies have to be implemented. It also means that a proper framework needs to be decided by taking inputs from everyone involved in the project. A BIM execution plan must be developed and proper care must be taken to see that it is being followed. Moreover, it also means that proper collaboration needs to occur between all the members of the project so that no information is lost and everyone remains on the same page. BIM provides all the tools for enhanced collaboration like Revit Server which allows the users across the WAN to work together efficiently while BIM 360 which allows multi-disciplinary teams to be connected to data in real time so that as soon as change is made everyone can see it instantly. Clash Avoidance is the ideal first step towards a coordinated BIM model, as proper collaborated and streamlined modelling approach can save up a lot of time.

2. Clash Detection:

Clash Detection unlike clash avoidance is a reactive process. Even though all the precautions are taken there is still margin of error. It is here clash detection is of paramount importance. AEC professionals can use Clash Detection software like Navisworks to detect any interferences taking place at an inter discipline or intra disciplinary level. There are three kinds of clashes, hard clash occurs when two components are occupying the same place. For instance, a hard clash occurs between Structural BIM and MEP BIM Services a duct running through a structural beam. A soft clash occurs when any object is not given the required geometric tolerance or its buffer zone is breached. Finally, a workflow clash is with regards to scheduling conflicts. A zero level of tolerance is not feasible and thus, the BIM modeler also needs to set a permissible level of tolerance below which any clash detected can be ignored. These clashes can be then solved onsite.

3. Clash Resolution:

Once the clash is detected the next step in BIM Coordination Services is to generate clash reports and send it to the concerned person or department. For instance, if there are large number of errors in plumbing then it needs to be sent to the MEP department. It is essential that clashes are dealt with so that they can avoid any unnecessary design alterations and the intent of the design is maintained. Once the design has been changed a sanity check is run again to ensure that the 3D model is actually clash free. Clash Resolution ensures that the hard and soft clashes are dealt with and thus there is no waste of time, cost and resources during the onsite construction process.

Conclusion:

Though clash avoidance, clash detection and resolution maybe different they all work towards the same goal of ensuring that the final BIM model is without any clash which could have adverse effect during the onsite construction.

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