Instruction Example 8.3.: Double-block Pile

This example serves to practise the construction of a double-block pile. Block-type piles are applied for high-quality timber only.

Material

Figure

Unedged-sawn boards completely belonging together, originating from at least two tree trunks or partial lengths from one tree trunk

Dimensions:
Width:	as available
Length:	at least 2000 mm
Thickness:	at least 25 mm

Tools

Metal hammer 250 g to 500 g

Measuring and testing means

Measuring tape or folding rule, long straightedge, stretching line, water level

Auxiliary accessories

Pile strips
Dimensions:
Width:	25 mm to 50 mm
Length:	double the bigger board width (trunk diameter) + 200 mm
Thickness:	at least 25 mm
Ladders (scaffold), covering plates, identification plate, nails

Necessary previous knowledge

Types of wood, properties of wood, measuring, testing, preparation of a sawn timber storage yard

Sequence of operations	Comments
1. Check the prepared timber yard and pile base for meeting of requirements.	Check the position of the pile stones for joint horizontal and aligned height as well as for straightness in length and width by means of long straightedge or stretching line and water level. Check the position of the squared timbers.
2. Arrange the boards to origin with respect to tree trunk and to order of sequence.	Measure and compare the width of the boards. Visually check and compare the course of the longitudinal edges of the boards and of the annual rings (at the cross-sectional areas).
3. Put pile strips longitudinally on the squared timbers of the pile base.
4. Put two outer boards from different trunks (blocks) side by side and transversely on the pile strips.	The faces of the boards nearer to the heart to show upwards. Ensure a sufficient centre distance of the boards to each other and to the outside in accordance with the biggest board width of the trunks (blocks).
5.. Put the second layer of pile strips on the first layer of boards as per step 3. above.	Put the pile strips exactly vertically above the pile strips beneath (check with water level).
6. Put on the next two boards according to step 4. above.	Take into account the comments on step 4. above.
7. Repeat steps 5. and 6. above until the last two outer boards of the different blocks are stored.
8. Continue storing boards from other trunks on the lower blocks according to steps 3. to 7. above until the intended pile height is reached.
9. Cover the top of the double-block pile with covering plates.	Secure the covering plates by fixing them against weather influences.
10. Identify the pile by fixing an identification plate.

Double-block Pile