Parapets are designed to satisfy different containment levels. The containment level represents the magnitude of impact that the parapet is supposed to uphold.
A parapet designed as low containment level can hardly withstand the impact by large vehicles which may even damage the parapet. On the other hand a parapet designed as high containment level can effectively contain safety large vehicle. However, when it is collided by light vehicles, it is expected that it would cause considerable damage to the light vehicles and its passengers on board. Therefore, strong parapets may not necessarily mean a good parapet.
This question is taken from book named – A Self Learning Manual – Mastering Different Fields of Civil Engineering Works (VC-Q-A-Method) by Vincent T. H. CHU.
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