Guest Post By James L. Gordon, P. Eng. (Ret'd)
On
May 1st, I read with mounting astonishment the aDB Engineering
report dated April 20, 2017, on their investigations into the causes of the
collapse, which occurred on 29th May, 2016.
The
level of incompetence described in the report is so widespread that it brings
into question the integrity of all other structures in the development. All
staff, from carpenters to engineers are included within the ranks of the
incompetent. The sub-standard construction was clearly visible to all, but
nothing was done to rectify the errors.
The
collapse occurred in the lower portion of the draft tube as shown on the
following Figure1, copied from Figure 2 in the aDb report. In this area, the
water passage changes from a vertical expanding cone to an almost horizontal
expanding rectangle as shown in Figure 2. It is the most complex double-curved
shape in the project and very difficult to build.
For
small turbines, the shape is formed in timber, with an east coast shipwright
engaged as the carpenter foreman. A shipwright carpenter is the only person
capable of cutting and shaping the timber to the required complex shape.
