Estimation Model for Concrete Slump Recovery by Using Superplasticizer
This paper aimed to introduce the solution of concrete
slump recovery using chemical admixture type-F (superplasticizer,
naphthalene base) to the practice in order to solve unusable concrete
problem due to concrete loss its slump, especially for those tropical
countries that have faster slump loss rate. In the other hand, randomly
adding superplasticizer into concrete can cause concrete to segregate.
Therefore, this paper also develops the estimation model used to
calculate amount of second dose of superplasticizer need for concrete
slump recovery. Fresh properties of ordinary Portland cement
concrete with volumetric ratio of paste to void between aggregate
(paste content) of 1.1-1.3 with water-cement ratio zone of 0.30 to
0.67 and initial superplasticizer (naphthalene base) of 0.25%-1.6%
were tested for initial slump and slump loss for every 30 minutes for
one and half hour by slump cone test. Those concretes with slump
loss range from 10% to 90% were re-dosed and successfully
recovered back to its initial slump. Slump after re-dosed was tested
by slump cone test. From the result, it has been concluded that, slump
loss was slower for those mix with high initial dose of
superplasticizer due to addition of superplasticizer will disturb
cement hydration. The required second dose of superplasticizer was
affected by two major parameters, which were water-cement ratio
and paste content, where lower water-cement ratio and paste content
cause an increase in require second dose of superplasticizer. The
amount of second dose of superplasticizer is higher as the solid
content within the system is increase, solid can be either from cement
particles or aggregate. The data was analyzed to form an equation use
to estimate the amount of second dosage requirement of
superplasticizer to recovery slump to its original.
[1] Tangtermsirikul S., Khungthongkeaw J., Kitticharoenkiat P. (2001). A
model for predict workability of fresh mortar and concrete, J. Materials,
Conc. Structure Pavement, JSCE, No. 676/V-51, 149-157.
[2] Ravina D., Soroka I. (1994). Slump loss and compressive strength of
concrete made with WRR and HRWR admixtures and subjected to
prolonged mixing, Cement and Concrete Research, 24, No. 8, 1994, pp.
1455-1462.
[3] Helge Hodne (2007) Rheological Performance of Cementitious
Materials Used in Well Cementing. Doctoral Thesis, University of
Stavanger, Norway.
[4] Hattori et al. (1979). Experiences with mighty superplasticizer in Japan,
Proceeding of the 1st CANMET/ACI conference on superplasticizer in
concrete.
[5] R. H Dhakal et al. (2013). Re-dosing superplasticizer to regain slump on
concrete with fly ash, EASEC-13.
[1] Tangtermsirikul S., Khungthongkeaw J., Kitticharoenkiat P. (2001). A
model for predict workability of fresh mortar and concrete, J. Materials,
Conc. Structure Pavement, JSCE, No. 676/V-51, 149-157.
[2] Ravina D., Soroka I. (1994). Slump loss and compressive strength of
concrete made with WRR and HRWR admixtures and subjected to
prolonged mixing, Cement and Concrete Research, 24, No. 8, 1994, pp.
1455-1462.
[3] Helge Hodne (2007) Rheological Performance of Cementitious
Materials Used in Well Cementing. Doctoral Thesis, University of
Stavanger, Norway.
[4] Hattori et al. (1979). Experiences with mighty superplasticizer in Japan,
Proceeding of the 1st CANMET/ACI conference on superplasticizer in
concrete.
[5] R. H Dhakal et al. (2013). Re-dosing superplasticizer to regain slump on
concrete with fly ash, EASEC-13.
@article{"International Journal of Architectural, Civil and Construction Sciences:71617", author = "Chaiyakrit Raoupatham and Ram Hari Dhakal and Chalermchai Wanichlamlert", title = "Estimation Model for Concrete Slump Recovery by Using Superplasticizer", abstract = "This paper aimed to introduce the solution of concrete
slump recovery using chemical admixture type-F (superplasticizer,
naphthalene base) to the practice in order to solve unusable concrete
problem due to concrete loss its slump, especially for those tropical
countries that have faster slump loss rate. In the other hand, randomly
adding superplasticizer into concrete can cause concrete to segregate.
Therefore, this paper also develops the estimation model used to
calculate amount of second dose of superplasticizer need for concrete
slump recovery. Fresh properties of ordinary Portland cement
concrete with volumetric ratio of paste to void between aggregate
(paste content) of 1.1-1.3 with water-cement ratio zone of 0.30 to
0.67 and initial superplasticizer (naphthalene base) of 0.25%-1.6%
were tested for initial slump and slump loss for every 30 minutes for
one and half hour by slump cone test. Those concretes with slump
loss range from 10% to 90% were re-dosed and successfully
recovered back to its initial slump. Slump after re-dosed was tested
by slump cone test. From the result, it has been concluded that, slump
loss was slower for those mix with high initial dose of
superplasticizer due to addition of superplasticizer will disturb
cement hydration. The required second dose of superplasticizer was
affected by two major parameters, which were water-cement ratio
and paste content, where lower water-cement ratio and paste content
cause an increase in require second dose of superplasticizer. The
amount of second dose of superplasticizer is higher as the solid
content within the system is increase, solid can be either from cement
particles or aggregate. The data was analyzed to form an equation use
to estimate the amount of second dosage requirement of
superplasticizer to recovery slump to its original.", keywords = "Estimation model, second superplasticizer dosage,
slump loss, slump recovery.", volume = "9", number = "12", pages = "1588-6", }