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Journal of Wuhan University of Technology-Mater. Sci. Ed. www.jwutms.net Oct.2017
1115
DOI 10.1007/s11595-017-1719-2
Preparation and Performance Research of Cement-based
Grouting Materials with High Early Strength and Expansion
ZHANG Yi1, LI Wei2, LI Dongxu3*
(1.Key Laboratory of Metallurgical Emission Reduction & Resources Recycling, Ministry of Education, College of Material Science and Engineering, Anhui University of Technology, Maanshan 243002, China; 2. AIRT New Materials Co. Ltd, Nanjing 211505, China; 3.College of
Material Science and Engineering, Nanjing Tech University, Nanjing 210009, China)
Abstract: Main performance of the cement grouting materials made up by Portland cement(PC) and
sulphoaluminate cement(SAC) was investigated in this program, a kind of expanding agent(EA) which was
mainly constituted by metakaolin and alunite was utilized for the compensation of the shrinkage, the hydration
products and micro structure of the grouting materials were researched by X-ray diffraction(XRD) and scanning
electron microscopy (SEM). The results showed that a high expansion rate of the grouting materials could be
reached as the expanding agent mixed in 6% of PC mass; the addition of SAC in the S2(PC:SAC:EA=34:6:2.25)
brought a further improvement of the expansion rate of the grouting materials, the analysis of XRD and SEM
showed that due to the reaction of expanding agent and SAC in the grouting materials, more ettringite crystal
was generated, which resulted in a higher early strength, the addition of SAC played an expansion and strength
reinforcement role in the grouting materials.
Key words: grouting materials; expanding agent; sulphoaluminate cement; hydration products;
performance research
1 Introduction
Cement-based grouting materials are a kind of
cement mortars that have the characteristic of high
fluidity, high early strength, and minor expansion. It has
been widely used in industry programs such as concrete
structure and building rapid repairing, secondary
grouting of pedestal plates of steel framework, quick
repairing of cement concrete pavements, pot rubber
bearing of high speed rail and so on, compared with
chemical grout, the special performance of cement
grouting materials made it a broad application
prospects[1].
Performance of grouting materials is influenced by
various factors such as water-to-cement(w/c) ratio, sand
grading, cement and other admixtures[2-4], on account
of the strength development requirements[5], Portland
cement is always used as a necessary ingredient in the
¦uhan University of Technology and Springer Verlag Berlin Heidelberg 2017
(Received: Aug. 12, 2016; Accepted: May 4, 2017)
ZHANG Yi(??): Ph D; E-mail: zhangyi1987@ahut.edu.cn
*Corresponding author: LI Dongxu(???): Prof.; Ph D;
E-mail: dongxuli@ahut.edu.cn
Funded by the National Key Technology R&D Program in
the12th Five Year Plan of China (No. 2011BAE14B06) and the
National High Technology Research and Development Program of
China (No. 2015AA034701)
grouting materials, aluminate cement(AC) or SAC
that have a high early strength and high expansion
characteristic is also used as an alternation with PC
for the composition of multiple cementing materials.
Dispersant additives such as superplasticizer in the
grouting materials could reduce the w/c ratio to obtain
an appropriate rheological property[6,7], assured the
grouting materials with higher viscosity and longer
setting time[8]. Beside that, supplementary cementing
material such as fly ash, granulated furnace slag, steel
slag and limestone powder are now successfully used
as components in the grouting materials and have
demonstrated to be effective for the performance of
the grouting materials[9,10]; recent work has showed
that alkaline activated fly ash can be used as cementing
materials of the grouting materials [11] ; moreover,
rheological behavior of the grouting materials could
be modified by silica fume and rice husk ash[12,13], and
metakaolin in the grouting materials resulted in an
improvement of the mechanical strength[14].
The main objective of this study was to develop
the grouting materials with high mechanical strength
and expansion rate, on the basis of the cementing
materials made by PC, expanding agent and SAC
were used and a further study of the grouting materials
was carried out, the main performance of the grouting
materials and the hydration mechanism were studied.
Vol.32 No.5 ZHANG Yi et al: Preparation and Performance Research of Cement-based ...
1116
KAl3(SO4)2(OH)6 (alunite), the active component of
the metakaolin are vitreous phase that has a poor
diffraction peak, such as SiO2�l2O3, unformed Al2O3
and SiO2, XRD pattern of the expanding agent is shown
in Fig. 1.
2.2 Test methods
2.2.1 Macroscopic performance test
Prepared samples were cured for 24 hours in the
concrete standard curing room(20�?, ?95%RH),
then the samples were removed from the molds for a
water curing(20�?) to the specified age. The slump
test and the vertical expansion rate of the grouting
materials was tested according to the ?code for
application technique of cementing grout?(GB/T504482008)[15], the compressive strength test of the grouting
mortar was according to the ?methods of testing cement
mortar strength? (GB/T 17671-1999).
2.2.2 Microscopic test
After 1, 3 and 28 d curing, samples were
crushed and immersed in absolute ethyl alcohol to
stop hydration, XRD patterns were obtained with a
Rigaku, models D/max2RBX, with an X-ray source
operating at 40 kV and 100 mA, the scans covered the
2? range 5-80�, radiation was CuK? with a wavelength
of ?=1.541 80 � with a nominal step size of 0.02� 2?,
SEM analyses were performed on a JSM-5900 electron
microscope, after 3 days curing.
2 Experimental
2.1 Materials
Grade 52.5 ordinary Portland cement, complying
with ASTM C-150 type I, from Jurong Taiwan
Cement Company; 525 sulphatealuminiate cement,
complying with GB20472-2006, from Zhenzhou
Zhongtai cement corporation; redispersible emulsion
powder, VINNAPAS-5044N, from Wacker Chemie
AG; hydroxypropyl cellulose ether(HPC), 8000mPa穝
of viscosity index, from Huzhou Zhanwang
Pharmaceutical Co., Ltd; superplasticizer(SP),
SUNBOPC-1016, from Suzhou Sunbo Chemical
Building Materials Co., Ltd; defoaming agents(DA),
P823, from Shandong Bangde Chemical Co., Ltd;
early strength agent(ESA), from Shanghai Huating
Chemicals Factory, Co. Ltd were used. Chemical
composition of the cement used in this experiment is
shown in Table1.
Expanding agent(EA) used in this experiment
is a mixture of metakaolin, CaSO 4 � 2 O and
3 Results and discussion
3.1 Effect of expand agent on the performance
of grouting materials
To investigate the effect of expanding agent on
the grouting materials made by PC, expanding agent
was added in the cement mass ratio that various from
2%-14%, the effect of expanding agent on the fluidity,
Fig. 1 XRD pattern of the expanding agent
Table 1 Chemical composition of cement/wt%
Composition
SiO2
CaO
Al2O3
SO3
Fe2O3
MgO
K 2O
TiO2
Na2O
P 2O 5
Loss
PC
18.98
66.42
5.03
3.78
3.16
0.60
0.79
0.23
0.15
0.06
0.80
SAC
7.03
44.84
22.10
16.56
1.73
5.85
0.89
0.60
0.02
0.13
0.25
Table 2 Influence of expanding agent on the performance of PC grouting materials
Technical index
Mixing amount/%
Initial fluidity/mm
30 min fluidity/mm
1d
Compressive strength/MPa
?
?
?
?380
?340
?290
?340
?310
?260
?20
0
2
6
10
14
354
350
342
330
313
337
332
321
307
288
22.1
21.3
20.5
17.8
12.6
3d
?40
48.2
41.8
40.6
35.0
33.2
28 d
?60
72.5
69.5
63.8
54.6
49.5
?0.02
-0.010
0.011
0.027
0.033
0.043
Vertical expansion difference between 3 and 24 h/%
Journal of Wuhan University of Technology-Mater. Sci. Ed. www.jwutms.net Oct.2017
compressive strength and vertical expansion of the
grouting materials is shown in Table 2, the technical
index of the parameters are according to the GB/T
50448-2008.
As shown in Table 2, the addition of expanding
agent results in a decline of fluidity value and compressive strength, and a significant expanding effect could
be seen from the variation of vertical expansion difference. For the technical performance requirements of the
grouting materials, a better performance was reached
at the mixing amount of 6% corresponding to the
expansion ratio of 0.027%. For the further improvement
of the grouting materials, SAC was introduced in the
grouting materials, based on our previous work, a better
mix ratio that satisfied the standard requirement [15]
is shown in Table 3, the performance of the grouting
materials is shown in Table 4, S1 represents the sample
made up by PC, S2 represents the sample made up
by PC and SAC, SAC mixed in the mass proportion
of 15% replacement of PC, compared with S1, the
addition of SAC(S2) resulted in an improvement of the
compressive strength and expansion rate, an obvious
expansion rate of 0.039% was reached only with a
small shrinkage of the fluidity.
3.2 XRD analysis
The hydration products of S1 and S2 researched
by XRD at different age are shown in Fig. 2. From the
XRD patterns of 1 and 3 d, the main hydration products
were Ca(OH)2, 3CaO稟l2O3�aSO4�H2O(ettringite)
and C-S-H gel, large number of unhydrated Ca3SiO5,
Ca2SiO4 and Ca4Al6SO16 were existing in the samples,
the stronger diffraction peaks of Ca(OH) 2, Ca 3SiO 5
and Ca2SiO4 in S1 showed a faster hydration reaction
of PC. Due to the hydration reaction of Ca4Al6SO16,
more ettringite was generated in S2, the generation
of ettringite provided a good expansion effect for
the grouting materials [16]. From the 28 d hydration
products of S1 and S2, the peak intensity of Ca(OH)2
was strengthened, which showed that the unhydrated
1117
Ca3SiO5, Ca2SiO4 took part in the hydration reaction,
more C-S-H gel was produced that provided a high
mechanical strength of the grouting materials.
3.3 SEM analysis
Micro structure of the grouting materials
was researched by SEM, for the comparison of the
hydration products and based on the mix proportion
of S1, S0 represents the sample that prepared with no
expanding agent added (Fig.3).
Fig.2 X-ray diffraction patterns of the samples at 1, 3 and 28 d
(A: Ca(OH)2; B: 3CaO� Al2O3� 3CaSO4 �H2O;
C: Ca3SiO5; D: Ca2SiO4; E: Ca4Al6SO16)
Table 3 Mix proportion of grouting materials with different cement composition/wt%
Composition
PC
SAC
Aggregate
EA
5 044 N
SP
HPC
DA
ESA
w/c ratio
S1
37.50
0
62.50
2.25
2.00
0.80
0.03
0.80
1.00
0.40
S2
34.00
6.00
60.00
2.25
2.00
0.80
0.03
0.80
1.00
0.40
*Aggregates composition: 40-70 mesh sand, 70-140 mesh sand, 400 mesh heavy calcium powder, mixed in the mass ratio of 2:2:1
Table 4 Results of the grouting materials with different cement compositions
Compressive strength/MPa
Performance
parameters
Initial fluidity/
mm
30 min fluidity/
mm
1d
3d
28 d
Vertical expansion difference between 3 and 24 h/%
S1
342
321
20.5
40.6
63.8
0.027
S2
330
326
23.1
44.5
70.6
0.039
Vol.32 No.5 ZHANG Yi et al: Preparation and Performance Research of Cement-based ...
1118
From the SEM analysis of the S0 in the 3 d,
little ettringite crystal could be seen in the structure,
the hydration products was not closely linked and a
loose structure was formed in its early hydration age,
on the contrary, needle ettringite crystals could be
clearly observed in S1 and S2, which were connected
together with the C-S-H gel to form a dense structure,
and for the S2 sample, due to the hydration of SAC
in the early age, a more intensive network with a
higher early strength was formed, which entrusted the
grouting materials with a good mechanical strength and
expansion performance. Related reaction concerned
with the ettringite are as follows:
Reaction related with expanding agent:
Al2O3+3Ca(OH)2+3CaSO4?3CaO?3CaSO4?32H2O
SiO2?2Al2O3+7Ca(OH)2+6CaSO4+55H2O?
2[3CaO?Al2O3?3CaSO4?32H2O]+C?S?H
KAl3(SiO4)2?(OH)6+13Ca(OH)2+5CaSO4+78H2O?
3(3CaO?Al2O3?3CaSO4?32H2O)+2KOH
Reaction related with SAC:
Ca4Al3SO16+2(CaSO4?2H2O)+34H2O?
3CaO?Al2O3?3CaSO4?32H2O+2(Al2O3?3H2O)
3Ca(OH)2+3CaSO4?2H2O+3(Al2O3?3H2O)
+20H2O?3CaO?Al2O3?3CaSO4?32H2O
4 Conclusions
A detailed research was made on the preparation
of grouting materials that used PC and SAC as
cementing material, the results showed that for the
Fig. 3 Micro structure of the grouting materials after 3 d curing
grouting materials made by PC, a good performance
can be achieved as the expanding agent admixed
with the amount of 6% cement mass, the property of
cement grouting materials decreased with the further
improvement of expanding agent amount.
Expansion rate of the grouting materials
increased significantly as SAC mixed in the proportion
of 15% total cement mass as replacement of PC,
the mechanical strength of the grouting materials at
different curing age was also improved.
Certain amount of expanding agent and SAC is
effective for the performance of the grouting materials,
which provide the grouting materials with a high
mechanical strength and expansion rate.
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