Date: xxx
Ref: xxx
Kind Attn :Mr. xxx
Project: 2B + G + 14+ Lower Roof Hotel Building on Plot No. xxx at Al Barsha 1st, Dubai
Subject: Addition of admixture in Approved Mix Design to Overcome Friction Losses and Maintain Design Slump at Slab Pouring Level (attached mix design 60N/ mm²)
Dear Sir,
With reference to above subject, as we experience in last 2 slabs that there is a change in concrete slump due to friction losses as well as viscous behavior of GGBS and kindly note the following:
1. Because of the height and the reasons mentioned above for friction and viscous behavior our designed slump
being reduced at pouring level from 200mm to 150mm slump.
2. As slump being changed the workability is being reduce and we are not able to compact and vibrate the concrete properly, so chances of having honeycomb in some places and it will increase more at next level.
3. Our Pump pipeline was jammed / Blocked in many times and very danger and serious for us to clear it and we are facing financial losses/ damage if we continue the same mix.
4. Due to workability and friction losses there will be more shrinkage crack due to the sudden drop of the slump and other natural losses.
So we approach the concrete supplier to maintain their mix design and they suggest the solution to add admixture Complast RP 264 to overcome the friction losses and maintain the viscous behavior of GGBS to provide the workable mix and to avoid any negative consequences because of pumping height which is more than 40m now by maintaining our mix design.
This is for your kind intimation and copy attached that NO CHANGES OF OUR MIX DESIGN only add the admixture to overcome the problem.
Regards,
For xxx Contracting L.L.C.
xxx
Project Manager
