First, the answer to Vol. 35 (last week).
Thank you for your responses! All of you were into the details on this one! Most of you were on the same page with your answer – the success of the extrusion weld would depend on proper preparation, as did the unsuccessful fusion wedge weld of the tie-in. In the photo, you can see them grinding the dirty geomembrane, which just transfers dirt particles – many CQA plans and technical specifications refer to the grinding/abrasion process as: “clean the geomembrane by abrading prior to extrusion welding”, which is an incorrect understanding (unfortunately a common one) of what the grinding process is for.
The results speak for themselves as illustrated by the “after” photo showing tracking of destructive failure which would encompass the entire 1000’ + tie-in by the time we were done.
Bonus background information: Tie-ins will always warrant destructive samples, which installers should know. Why they would further entice a CQA inspector by leaving their machine run unattended down the seam is baffling. The fusion destructs failed and the installer chose to weld the overlap flap, which was permitted on this jobsite – not a practice I recommend but in the long run I got a cap anyways.
In these blog posts, Do You See What Glen Sees, I will present a photograph or short video related to earthwork or geosynthetics construction and have you identify the significance of what you’re seeing.
It could be things being done correctly or incorrectly. Primarily, these will be things that impact quality.
In addition to my blog, I’ll post this content on X and LinkedIn. You can post your response on one of those two.
I’ll give you my thoughts on each photo or video when I post the next installment.
Do you see what I see? Or did you find something I missed? I’m excited to find out!
Here is the next installment. Take a good look. Do You See What Glen Sees?
Welcome to Volume 36 of ‘Do You See What Glen Sees?’!
This photograph should be fairly self-explanatory, and I primarily chose it for a point of discussion. This is a common occurrence this time of year in the northern hemisphere, as our daylight continues to decrease ahead of the colder weather everyone knows is coming anyday.
A bit of background behind this photograph – our CQA crew has been on-site since 6:30 am with the installer starting at 7 am. It’s 5:15 pm when I took this photograph right after the equipment shown here was dropped off. The installer usually begins winding down for the day about this time with shutdown at 6 pm. The installer is behind schedule with the general contractor (to whom they are a subcontractor) breathing down their neck wanting to place cover soil.
What do you see? What do you think?
Post your response on X or LinkedIn.
