CCIL laboratory testing
When do lab cured cylinders need to be demolded? - Answer -20 +/- 4 hrs after casting time
When do field cured cylinders need to be demolded? - Answer -28 +/- 8 hrs after casting time
Why can lab cured cylinders be demolded earlier than field cured cylinders? - Answer -This is because
field cured cylinders will need to be transported to a lab so they need the extra time to ensure that the
cylinders set properly before being moved around.
When are cardboard moulds used? - Answer -For concrete <35 MPA
What temperature should the curing tanks be kept at and how often should they be monitered. -
Answer -Temp. should be at 23 +/- 2 C and temperature recorder should be kept in the tank and
checked twice a day at least 5 days per week accurate to 0.5 C.
What should the tanks be saturated with ? - Answer -Calcium hydroxide
What ratio should the cylinders length be to its diameter? - Answer -2:1
Initial curing in "field" temp. ? - Answer -15 - 25 C
When can the demoulding time for field cured cylinders be 76 hrs? - Answer -If the following is provided:
i) 15 - 25 C
When do lab cured cylinders need to be demolded? - Answer -20 +/- 4 hrs after casting time
When do field cured cylinders need to be demolded? - Answer -28 +/- 8 hrs after casting time
Why can lab cured cylinders be demolded earlier than field cured cylinders? - Answer -This is because
field cured cylinders will need to be transported to a lab so they need the extra time to ensure that the
cylinders set properly before being moved around.
When are cardboard moulds used? - Answer -For concrete <35 MPA
What temperature should the curing tanks be kept at and how often should they be monitered. -
Answer -Temp. should be at 23 +/- 2 C and temperature recorder should be kept in the tank and
checked twice a day at least 5 days per week accurate to 0.5 C.
What should the tanks be saturated with ? - Answer -Calcium hydroxide
What ratio should the cylinders length be to its diameter? - Answer -2:1
Initial curing in "field" temp. ? - Answer -15 - 25 C
When can the demoulding time for field cured cylinders be 76 hrs? - Answer -If the following is provided:
i) 15 - 25 C
