Forest Management and Roads Flashcards
What is the general cost of road building?
50,000 - 150,000 per kilometre
What is a Road Standard?
A design spec that sets limits to: -Subgrade and surface width -Maximum and minimum curvature -Vertical curvature -Favourable and adverse grades -Density of turnouts, lanes, surface materials MOFL uses class I - V I: highway V: goat path
Why would you want a high turnout density?
If the road is busy, turnouts can help the flow of traffic and increase safety.
Give some features of temporary roads
- abandoned or deactivated after logging
- only limitations are usually physical limits of the trucks
- All weather roads are surfaced and summer roads are not
What does “surfacing” imply
When a layer of crushed rock is added to native material to increase the usability of the road (all weather).
Give some features of permanent roads.
- Planned for many years of use
- Further classified as Main or Secondary based on volume harvested, public use, safety and travel speed…
What are typical spur road standards?
- Subgrade width = 6m
- Surface width = 5m
- Curve radius = 20m
- Max favourable =18%
- Max Adverse = 10%
What is a favourable grade? What are the limits?
Downhill for a loaded truck.
18% max
What is an adverse grade? Whats the limit?
Uphill for a loaded truck.
10% max
What is the clearing width?
Width between standing timber
What is a right of way? How wide are they?
-Typically 20m, specified by the permit. The full area that you have been granted for building a road.
How can you figure out which standard to use?
Sum the cost of 4 major factors and choose the lowest cost.
- Trucking cost - decreases with higher standards
- Road construction cost - increases with higher standard
- Road maintenance cost - generally increases with higher standards
- Interest Cost
What is the goal of a logging engineer when designing roads?
minimize combined cost of…
- yarding
- skidding
- road construction
- maintenance
- trucking
A good road location considers these 5 things…
- Within skidding / yarding range limits from block boundary
- Location must be appropriate for equipment being used (deflection/landings)
- Meet standards for grades, alignment, width and bearing strength.
- Meet environmental standards
- Consider future roads
What is a control point? differentiate positive and negative CPs
- A place on the hillside that influences road placement
- A rock bluff is a negative control point because we want to avoid it.
- A bench is a positive control point because it provides flat ground for logging equipment.
Success in logging is all about…
Good location of roads
What is a general rule of thumb with respect to harvest systems when building roads?
Choose the harvesting system first, then engineer the road to suit the harvest system.
Differentiate main branch and spur roads
Main: designed and located for hauling efficiency
Branch: often a balance between main and spur
Spur: designed and located to suit the harvest system, primarily for yarding efficiency.
Where would you locate your road on a slope if your plan was to ground base harvest the bitch?
Road located low to avoid adverse forwarding/skidding
Where would you locate your road if using a cable harvesting system?
High on the slope since cable systems are best when yarding uphill.
How would you plan a block for minimal stream impact?
Use as little road as possible
What are some common levelling errors?
- Bubble not centred
- Rod not plumb
- FS and BS unequal distance
- Rod in unstable location
- Reading rod incorrectly
- Recording reading incorrectly
What does datum refer to?
zero elevation (sea level)
Name 6 CP’s
Switch backs (+) Saddles (+) Stream crossings (+) Rock (-) Property Boundaries (-) Unstable areas (-)
