BIM Clash Detection

Clash Detection or Conflict Detection is very critical in the construction industry as design planning is a dynamic field that requires viable coordination between the stakeholders for desired outcomes. Any construction design typically includes stakeholders such as engineers, architects, contractors, suppliers and vendors, sometimes making the project completion process highly complex and mind boggling.  On top of it, the increasing global population pushes the demand for sustainable and efficient residential or commercial structures, healthcare, hospitality and transportation facilities. In such a situation, BIM clash detection techniques give precision and sustainability to construction plans and are the basic components during the conceptual design stage. Why Clashes Happen? Clashes or Conflicts in the construction design occur due to disorganized coordination among the stakeholders who come together to work on different aspects of construction projects. A Clash happens when elements that make up a built facility are not spatially synchronized and conflict This irreversibly impacts project cost and schedule. Clashes happen due to: Intersection of components of different disciplines sharing the same space Absence of buffer area around hardware Conflict between workflow and facilities scheduling Clash or Conflict Detection: What, How and Why? Clash Detection is the procedure of identifying if(where or how) two or more parts of the building or facility (e.g., plumbing, walls, beam, ducts, etc.) are conflicting with one another. Clash detection ensures each and every component works in harmony and nothing is incompatible. Types of BIM Clash Detection 1. Hard Clash Hard clash is a type of conflict that includes geometry-based issues. This occurs when two or more objects are conflicting with one another, it could be plumbing going through a surface in the incorrect way or a duct conflicting with a pipe or it could be an air-conditioning duct going within a load-bearing wall. Hard clashes are identified by implementing geometrical, semantic, and rule-based instructions on the BIM object with inserted information. Tools like Navisworks recognize clashes like a beam going over a pipe whereas the rule-based clash detection on embedded object data excludes the common mistakes like pipe going through a wall or MEP against roof. 2. Soft Clash Soft clashes occur when a component is not provided the sufficient spatial or geometric threshold it requires. This results in encroachment into geometric tolerances set for other objects and as the buffer or cushion zone is breached, Soft clash occurs. For instance, a HVAC framework needs space to consider for maintenance workers to function in to service the framework. In the event that the building configuration does not have that space, soft clash occurs, MEP components like air conditioning units, heaters, etc. usually need buffer space for safe and easy maintenance access. Implementing adequate object-related tolerance data to software like Navisworks can identify clashes as per applicable regulations and standards. 3. Work-flow clash or 4D clash Work-flow clash or 4D clash includes conflicts identified with contractor scheduling or sequencing, equipment, material delivery and general workflow timeline clashes. Despite the fact that these issues are not straightforwardly associated with design however they can essentially influence the project timeline. A work process conflict disrupts workflow efficiency and also have a domino impact, ultimately bringing the whole project to a standstill. Implementing 4D BIM Sequencing timeline in Navisworks brings scheduling conflicts to the forefront and streamlines the whole construction process. For instance, a HVAC maintenance plan that doesn’t change with the scheduled conveyance of extra parts.