High range superplasticizer special for subway tunnel segments (VF-4)
VF-4 is also suitable for pump concrete, precast concrete, fair-faced concrete, self-leveling mortar and etc.
Category
Polycarboxylate series
Detail
Applications
VF-4 is also suitable for pump concrete, precast concrete, fair-faced concrete, self-leveling mortar and etc.
Concrete of shield segment with VF-4 has great early strength function.
Concrete with VF-4 has good volume stability and can complete deviation value of physical dimension of shield segment is less than 1mm.
The surface of concrete member with VF-4 can reach the standard of fair-faced concrete which is bright external appearance, uniform color and less bubble.
Concrete with VF-4 has good thixotropy and won’t appear phenomenon of delamination and bleeding.
VF-4 has early strength and long-term strength.
VF-4 has less alkali content. It can increase durability of part and reduce alkali-aggregate reaction rate.
Properties
The dosage is typically 1.5%~3.5%, 2.0% is the best content.
VF-4 cannot be used with naphthalene based water reducing admixture.
Experiment must be done when VF-4 is used together with other admixtures.
Uniformity
Item |
Results |
Item |
Results |
Appearance |
Tan transparency liquid |
pH Value |
7-9 |
Density (20℃) |
1.09±0.02 g/ml |
Chloride ion (%) |
≤0.6% |
Sulfate ion content (%) |
2.9% |
Surface tension |
69(20℃dyn/c㎡) |
Concrete performance with 2.0% dosage by binder mass
Test items |
Classifications |
Results |
||
Standard |
Set Retarding |
|||
Water reducing rate (%), ≥ |
14 |
14 |
20 |
|
Ratio of bleeding rate (%), ≤ |
90 |
100 |
27 |
|
Air content (%), ≤ |
3.0 |
4.5 |
2.2 |
|
Difference in setting time(min) |
Initial setting |
-90~+120 |
﹥+90 |
+28 |
Final setting |
— |
+1 |
||
Ratio of compressive strength (%), ≥ |
1d |
140 |
— |
181 |
3d |
130 |
— |
171 |
|
7d |
125 |
125 |
161 |
|
28d |
120 |
120 |
145 |
|
Ratio of shrinkage(%),≤ |
28d |
135 |
110 |
Conclusion: the project is in line with “high performance water reducer” index of GB8076-2008.
Packaging, Transport and Storage
VF-4 is available in metal pail or iron tank. Other special package can also be available according to prior consultation.
VF-4 must be stored at the temperature above 0℃. Special measures should be taken to ensure entire package.
Dry and well ventilated warehouse is needed for storage. Quality guarantee of VF-4 is one year under normal conditions. If storage has surpassed the time, test must be done to confirm the validity.
Keyword
special
vf-4
concrete