Segregation and honeycombing occurred in a floor slab due to poor workability of concrete and late placement during hot weather. Loose concrete was chipped and the area was grouted and repaired with a bonding agent and cementitious material. To prevent future issues, proper supervision of batching and placing is needed, discharge times must be monitored, pour areas kept clean, and skilled laborers used for concrete work.

1. (Issue: Segregation and honeycomb.)
CASE STUDY ON
CONCRETE WORKABILITY.

2. SEGREGATION AND HONEYCOMBING FOUND IN
FLOOR SLAB DUE TO POOR WORKABILITY OF
CONCRETE AND LATE PLACING OF CONCRETE.

3. Reason of happening.
 Poor workability of concrete.
 Flow of concrete not checked periodically.
 Extended pouring time.
 Hot weather climate conditions.

4. Course of action taken.
 Loose concrete was chipped from the slab and washed with water.
 Grouting nozzles were fixed and grouted with Pidilite easy grout
chemical.
 After grouting Nito bond AR bonding agent was applied and same
was allowed to dry.
 Rendroc S2 mixed with water for required consistency and applied
over the surface around 10 to 15 mm thick and fair finish done.
 Repaired area cured for seven days.
 Followed by the repairing work the tool box talk was given to the
site engineer and concrete pouring worker to educate them on early
placing of concrete at dry weather condition.

5. Corrective action.
 Flow of concrete to be checked every Transit mixer at site also.
 Ensure adequate man power to quickly place, finish and cure the
concrete.
 The site quality personnel should monitor the discharging time of
concrete through transit mixer after batching done. If delay in
execution of concrete the batching to be stopped accordingly.
 Wrapping of hessian cloth(jute burlap) around transit mixer drum
and keep the drum in wet condition for day time concreting to retain
the slump flow.

6. How we ensure that the same is
not happening in future.
 Ensure proper supervising during batching and placing of concrete.
 Ensure the discharging time of concrete with delivery copy and
batching sheet.
 Ensure the pour area free from foreign materials and use of tray for
collecting of spilled concrete.
 Ensure skilled labours for placing and finishing of concrete.