Timber beam-end engineering repairs - Principal carrier split

Click on any of the images for a larger view.

This is a principal carrier in a detached stone building, possibly 400 years old. Viewed from the lower building line the beam appeared to have sagged.

The beam was carved out of an oak trunk, and a large branch came out from the cenral section of the beam. When cut and shaped this branch 'knot' couldn't be shaped into a straight line, so the carrier was cut to take into account the deflection now seen. An internal wall of brickwork was constructed at mid section at a later date because the beam has shown signs of distress. During refurbishment this wall was removed, causing the problem to resurface.

The client wanted the room put back into its original shape, but the problem of the split was of structural concern.

Top view of the carrier beam.

In theory this was a simple top slot repair. The oak had turned as hard as iron, with no insect damage or fungal decay. The slot width was 32 mm wide x 2 metres long x 220 mm deep.

For reference the split was recorded on the top surface of the beam.

The result of two days of timber removal.

That's what I call hard work!

Cleaning of the slot.

First dry fit - bar being lowered down.

Resins and bars.

Side shutters were installed and sealed to ensure a flat resin fill to the top bar.

First bar laid in the base of the trench.

Resin pour.

Next bar laid onto the resin and tamped down.

Final resin pour. Total number of steel bars laid was seven with 17.3 litres of structural pouring grout. I was very pleased with the result of this installation. It turned out to be the original conception of what the beam would have looked like with the defects no longer a problem.