A Self-Learning Manual - Institution of Engineers Mauritius

A Self-Learning Manual
Mastering Different Fields of Civil Engineering Works (VC-Q&A Method) Vincent T. H. CHU
Level One (Core FAQs)
Part III: Paving Blocks
1. How do concrete paving blocks take up loads? (S1)
The paving for concrete blocks consists of closely packed paving blocks in
pre-determined patterns and the tiny joint spaces between individual
blocks are filled with sand. The presence of sand avoids the displacement
of a single block unit from the remaining blocks. Moreover, the horizontal
interlocking provided by the arrangement of paving blocks in special
patterns (e.g. herringbone pattern) prevents any single block from moving
relative to one another. For instance, vertical loads acting directly on one
concrete paving block are not only resisted by the block itself, but also by
the blocks adjacent to it [59].
Fig. Paving blocks
2. What is the load transfer mechanism for paving blocks in
pedestrian footway? (S1)
In Hong Kong, footway is normally designed with paving slabs/interlocking
blocks instead of concrete because the extensive use of concrete in
pavement is boring. Moreover, poor appearance will result in concrete
pavement due to frequently trench openings for utility work. In addition,
owing to the prolonged setting and curing time of concrete, the use of
concrete pavement inevitably generates disturbance to the general public.
The pedestrian loads are taken up through the following ways:
(i) Load carrying capacity of paving slabs/interlocking blocks are derived
from their individual strength;
(ii) Pedestrian loads are also supported by interlocking forces provided
by friction transfer through the sand in vertical joints (K. K. Tang &
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