Problem Statement Shrinkage crack happened to be appeared on top surface of top deck and bottom deck of the segment. Normally appeared after 7 days age. Crack width is more than 0.2mm

Causing Factor Curing procedure is not doing properly Plastic shrinkage might due to settlement of the concrete at web area.

SHRINKAGE CRACK

The affected area is grind to get a clear crack

mapping

All the debris and dust is then cleared by using

vacuum cleaner

Preparation of epoxy by using Sikadur 31CF Normal

The crack line in then patched with epoxy and at

the same time nozzle is installed for injection

purposes

All the cracks had been sealed and installed with

nozzle.

The low viscosity injection liquids (Sikadur 52my )is then mix with the right

proportion.

The mixing of Sikadur 52my is now being injected

in every nozzle provided

After the injection liquid had harden, all the nozzle and rough surface is grind

until smooth

Finished surface

Problem Statement Severe honeycomb appeared at the bottom surface of the bottom deck of the segment. Happened at the critical part which is below the anchorage block.

Causing Factor Insufficient vibration applied. Low flow test of concrete was used. (Flow : 550mm)

HONEYCOMB

Honeycomb was spotted at the bottom of the

segment

The affected area is hacked until sound concrete

Sika Top Armatec-110 EpoCem then is applied to the steel as a debonding

agent

Formwork is fixed with inlet and outlet pipe

Sika Microcrete 2000 is mixed

Sika Microcrete 2000 is poured into the pressure

grout pump

The grout is pumped inside the affected area through

bottom inlet pipe

Both inlet and outlet pipe had to be sealed after fnish

grouting

Sample of the grout should be taken to test the

compressive strength

After demould the formwork, all the surface

need to be grind smoothly

Finished surface