Geoscience Reference
In-Depth Information
•
Trenching
1.0m deep typically requires shoring before it is considered safe to
enter an excavation.
>
•
When B
5H, ie a wide open cutting, this excavation is now considered an open
cutting rather than a trench.
>
Table 14.29
Safety in trenching.
Risk
Distance from edge of trench
High
(H
B)
<
+
Medium
(H
B) to 2 (H
B)
+
+
Low
2(H
B)
>
+
•
Stockpile/Equipment must be placed to minimise risk to the trench, unless trench
bracing designed to accommodate the loads.
•
Structures/Services at the above distance need to be also considered.
•
Movements when placed at
<
2(H
+
B) discussed in later chapters.
•
To minimise risk, corrective action and continuous observations for:
- Adverse dip of rock/soil layers.
- Loose/soft layers intersected.
- Water flow and seepage into trenches.
Search WWH ::
Custom Search