Accepted manuscript doi: 10.1680/jgeen.18 · 2020. 5. 22. · Accepted manuscript doi:...

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Submitted: 03 December 2018

Published online in ‘accepted manuscript’ format: 10 May 2019

Manuscript title: Behaviour of silty sands stabilised with cement subjected to hard

environmental conditions

Authors: Nilo Cesar Consoli1, Mariana S. Carretta

1, Helena B. Leon

1, Maria Eduarda B.

Schneider1, Naiara C. Reginato

1 and J. Antônio H. Carraro

2

Affiliations: 1Graduate Programme in Civil Engineering, Universidade Federal do Rio

Grande do Sul, Porto Alegre, Brazil and 2Department of Civil and Environmental

Engineering, Imperial College London, London, UK

Corresponding author: Nilo Cesar Consoli, Graduate Programme in Civil Engineering,

Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.

E-mail: [email protected]



Abstract

The present study evaluates the effect of three distinct amounts of fines, Portland cement and dry unit weights

on the accumulated loss of mass (ALM), maximum shear modulus at small strains (G0) and tensile strength (qt)

of stabilised sands subjected to wet-dry cycles. Tensile strength test results showed that addition of fines to a

sand stabilised with cement increased its tensile strength, irrespective of the dry unit weight (d) and cement

amount present in the mixture. Increasing the amounts of fines of compacted cement-stabilised silty sand

specimens subjected to wetting-drying cycles reduces ALM and increases G0 and qt of the mixtures. This may be

due to the fact that specimens with larger amounts of fines have more contact points amongst particles, which

provides better opportunities for the cement to develop more efficient bonds within the soil fabric, improving its

mechanical performance. The increase in cement content and in d of compacted cement-stabilized silty sand

specimens reduced their ALM and increased G0 after each one of the twelve wet-dry cycles. The G0 and qt of

cement-stabilized silty sand specimens with fines increases up to the sixth cycle, remaining practically constant

after that, when these specimens are subjected to wetting-drying cycles.

Keywords: Strength & testing of materials; geotechnical engineering; granular materials; nonplastic fines; soil

stabilization; Portland cement; stiffness; tensile strength; hard environmental conditions



INTRODUCTION

A dense layer of sandy soil stabilized with Portland cement superimposing weak soils

is a widespread technique used to enhance the bearing capacity of spread footings. Similar

approaches are used to improve base/subbase layers in pavements or the foundation layers for

pipelines. In these applications, failure typically starts with the development of tensile strains

at the bottom of the improved layer (Consoli et al. 2008; Consoli et al. 2009; Dormon and

Metcalf 1965). To understand the variation of durability, small-strain shear stiffness and

tensile strength of sandy soils stabilized with early-strength Portland cement exposed to hard

environmental conditions (through the use of wet-dry cycles), the assessment of their long-

term performance is required. However, previous studies have mainly focused on clayey

soils. These studies have tried to assess whether the improvements caused by Portland

cement/lime stabilization could be undermined by exposure to hard environmental conditions

such as those imparted by freezing-thawing (Consoli et al. 2017) or water circulation (Le

Runigo et al. 2009). The advantages of lime/cement stabilization of clayey soils have been

shown to be partially lost when the stabilized soil is exposed to hard environmental

conditions (Chittoori 2008; Stoltz et al. 2014; Consoli et al. 2018; Chittoori et al. 2018).

Thus, it is critical to understand the role of consecutive dry-wet cycles and their probable

influence on the behaviour of sandy soils stabilized with Portland cement. Another variable

that has been shown to be important in sandy soils is the content of fines. Carraro et al.

(2009) tested various mixtures of sands with either plastic or non-plastic fines and showed

that all aspects of the mechanical behaviour investigated in their study are affected by the

amount of the fines present in the sand. They found that the addition of nonplastic silt to the

host sand increases both the peak and critical state friction angles. Besides, G0 is affected

(reduced) by the amount of fines. Phan et al. (2016) studied the influence of low plasticity

fines content on sand-fines specimens at a given relative density and found out that as fines

content increase the internal friction angle decreases and the cohesion intercept increases.

Regarding liquefaction of sandy soils, Wang and Wang (2010) have shown that for a constant

dry density, the increase of fines content in a sand up to 30% decreases soil liquefaction

resistance with increasing fines content. Esseler-Bayat et al. (2017) have also shown that

clean sand specimens have higher liquefaction resistance compared with that of sands with up

to 10% of fines content. Looking at the effect of fines content in stabilised sands, Hataf and

Jamali (2018) have found that considerable increase in cohesion intercept of stabilized soils



can be achieved for sand specimens with up to 10% fines content.

The present study systematically evaluates the effect of fines content (10, 20 and

30%), Portland cement content (5, 8 and 11%) and dry unit weight (14.5, 15.5 and 14.5

kN/m3) on the accumulated loss of mass (ALM), maximum shear modulus at small strains

(G0) and tensile strength (qt) of compacted sandy soils stabilized with an early-strength

Portland cement subjected to wet-dry cycles to emulate exposure to hard environmental

conditions.

EXPERIMENTAL METHODS

Materials

High early strength Portland cement – PC III (ASTM 2016) was used in this study to

stabilize three nonplastic silty sands. The nonplastic silty sands were obtained by adding three

distinct amounts of nonplastic fines (10, 20 or 30%) to Osório sand. Osório sand is a uniform

fine silica sand with rounded particles and specific gravity equal to 2.63. A mineralogical

analysis conducted on the sample suggests that quartz is the predominant constituent present

in the sand particles. Osório sand is classified as SP according to the Unified Soil

Classification System (ASTM 2017a). Rice husk ash obtained from a rice company that

incinerates rice husk for power generation was used as fines. The specific gravity of rice husk

ash is 2.20. X-ray diffraction analysis (XRD) performed on rice-husk ash shows the presence

of cristobalite (SiO2) as the dominant mineral. X-ray fluorescence (XRF) tests revealed that

the studied ash is mainly composed of SiO2 (91%). Rice husk ash is classified as ML (ASTM

2017a). The particle size distributions of all materials tested are presented in Figure 1. Their

physical properties such as specific gravity (Gs), mean particle size (D50), etc., are

summarized in Table 1. According to the Unified Soil Classification System, mixtures of

Osório sand with 10, 20 or 30% of rice husk ash are classified as silty sands (SM). The

specific gravity of the Portland cement grains is 3.15. Distilled water was employed in all

stages of the testing program.

Specimen Preparation and Curing

Sample preparation started by dry mixing the sand with the required amount of Portland

cement until mixture homogeneity was visually observed. For all mixtures tested, the mass of

cement (mc) used was determined based on the target cement content (C) and the dry mass of

soil (ms) required to prepare each specimen so that C = mc / (mc + ms). Distilled water was

then added to the mixture until mixture uniformity was achieved. Each specimen was



statically compressed in three layers inside a cylindrical mould. Sample mixing and specimen

preparation was completed in less than an hour. Specimen diameter, length and mass were

determined immediately after the specimen was removed from the mould. Prior to any of the

testing procedures that will be described next, all specimens were cured for seven days inside

a room with humidity- and temperature-control at 95% and 22º±2ºC. Cylindrical specimens

with diameter and height equal to 50 and 100 mm, respectively, were used in the splitting

tensile strength testing program. Changes in durability and small strain stiffness of specimens

subjected to wetting-drying cycles were assessed on specimens with diameter and height

equal to 100 and 127 mm, respectively (ASTM 2015).

Splitting Tensile Strength Tests

Sandy soil-cement layers used as pavement base layer or as a stabilized base for spread

footings usually collapse once the tensile strength at the bottom of the stabilized layer is

reached (Dormon and Metcalf 1965; Consoli et al. 2011). As a result, splitting tensile

strength tests have been conveniently used to demonstrate the efficiency of Portland cement

stabilization for sandy soils. In this study, splitting tensile strength tests were conducted in

accordance to ASTM (2017b) using a 10-kN loading cell with resolution of 0.005-kN. All

splitting tensile strength test specimens were submerged in water for 24 hours before testing

to minimize suction effects. If suction is not reduced to smallest possible values (preferably

zero), it may have an undesirable strong impact on tensile strength.

This testing program was specifically developed to evaluate the effects of the porosity-

cement ratio (by systematically varying the dry unit weight and Portland cement content of

the specimens) and number of wet-dry cycles on the tensile strength of the three artificially

cemented silty sands tested. The target compaction parameters used for specimen preparation

were selected based on the standard Proctor compaction curve of the silty sand containing

10% of fines (Figure 2). As shown in Fig. 2, three target dry unit weight (d) levels of 16.5,

15.5 and 14.5 kN/m3 and a single target water content of 14 % were selected and used to

prepare the test specimens. These three target compaction levels were also adopted for the

other two percentages of Portland cement used (5 and 11%) leading to a total of 27

combinations among soil type, amount of cement and dry unit weights used.

Durability Tests Due to Wetting-Drying Cycles

Durability tests following wetting and drying cycles were carried out following ASTM

(2015) on all mixtures of nonplastic silty sands stabilized with Portland cement tested in this



study. This allowed assessment of the loss of mass of specimens due to the repeated (twelve)

wet-dry cycles followed by brushing strokes. Each cycle starts by oven drying the specimen

for 42 h at 71o±2

oC. Next, the specimens are brushed several times by applying a force of

13.3-N. At the end of each cycle, specimens are submerged in water for 5 h at 23o±2

oC.

In this testing program, the target variables used to prepare the specimens were similar

to the variables used for the splitting tensile strength tests (i.e., sandy soil type, cement

content, dry unit weight and water content). However, a reduced number of levels were used,

as summarized in Table 2, leading to a total of 6 combinations among soil type, amount of

cement and dry unit weight. Two specimens were prepared for each combination tested. The

first specimen was submitted to the regular brushing stroke procedure whereas the second

specimen (not brushed) was used to obtain the maximum shear modulus at small strains (G0)

through pulse velocity testing, as described next.

In addition to the specimens subjected to regular durability tests, a few well-performing

specimens of silty sands containing either 10 or 30 % of fines stabilized with the highest

Portland cement content (11 %) and dry unit weight (16.5 kN/m3) used in this study were also

prepared. These were subjected to additional splitting tensile strength tests after being

exposed to zero, 6 and 12 wetting-drying cycles carried out using the regular durability

testing protocol, except by the brushing stage, which was not carried out in such specimens.

Ultrasonic Pulse Velocity Tests

The measurement of ultrasonic pulse velocity followed ASTM (2008) and was used to

assess the maximum shear modulus at small strains (G0) for the second set of (unbrushed)

specimens prepared for the 10 combinations of testing variables used in the regular durability

tests, as described above. These measurements were carried out before the first cycle and

after cycles 1, 3, 6, 9 and 12.

RESULTS AND ANALYSIS

Tensile Strength

Figure 3a shows the variation of the splitting tensile strength (qt) as a function of the

porosity-cement index (/Civ), expressed as porosity () divided by the volumetric cement

content (Civ), the latter expressed as a percentage of cement volume regarding total volume,

which is raised to the adjusted exponent of 0.28 (Consoli et al. 2007, 2016) for fitting

purposes. Best-fit trendlines presented in Equations 1, 2 and 3 are also plotted in Fig. 3a,

which yield coefficients of determinations (R2) of 0.87, 0.89 and 0.83 for sands with 10, 20



and 30% fines, respectively. The experimental data shown in Fig. 3(a) includes

measurements obtained for the three silty sands stabilized with Portland cement after 7 days

of curing. For each silty sand dataset shown in Fig. 3, the corresponding trendline fits data

that includes all three Portland cement contents (5, 8 and 11%) and dry unit weights (14.5,

15.5 and 16.5 kN/m3) used in the experiments.

( ) [

( ) ]

(1)

( ) [

( ) ]

(2)

( ) [

( ) ]

(3)

A possible expression to specify the general relationship between qt and the

porosity/cement index for sandy soils stabilized with Portland cement was proposed by

Consoli et al. (2011) as stated in Eq. (4).

[

( ) ]

(4)

where Y, Z and D are empirical scalar parameters that must be determined experimentally for

a given stabilized sand.

In an attempt to provide physical significance to the existing empirical database,

Diambra et al. (2018) proposed a theoretical model based on the concept of superposition of

the failure strength contributions of the sand and cement phases to establish a link between

the inherent properties of sandy soil and Portland cement grains and the empirical

coefficients of Eq. (4). In summary, their analysis yields

[

( ) ⁄]

(5)

where k and b are also empirical scalar parameters that need to be determined for a given

stabilized soil mixture. By comparing the empirical and theoretically-derived Equations (4)

and (5), respectively, it becomes apparent that Z(=b) and D(=1/b) are not independent

parameters. Thus, if D=0.28 is used (e.g. Consoli et al. 2007, 2016), then b must be equal to

3.57, which is similar to the empirical value of 3.60 derived from the experiments and used to

fit Equations (1) to (3).

Alternatively, Eq. (5) may be simply re-written as



(6)

If no attempt is made to optimize the fitting between the experimental data and Eq. (6),

resulting in ( ⁄ ), it can be seen from Fig. 3b that the use of the reciprocal of the

porosity-cement index as the independent variable already leads to coefficients of

determination above 0.70. This may have several advantages. First, the tensile strength is

shown to be directly proportional to the volumetric cement content and inversely proportional

to the porosity of the mixtures, as expected. Secondly, the resulting expression is simple and

requires evaluation of a single empirical parameter (K). The physical meaning of this single

empirical parameter K requires further analysis and additional knowledge of inherent fabric

characteristics of the mixtures tested, which are outside the scope of the present manuscript.

However, the existing data clearly shows that K has a strong correlation and linearly

increases with the amount of fines present in the mixtures tested (Figure 4). Other fabric

characteristics such as the coordination number (Z) (Thornton 2000) may be related to K as

well, but this is out of the scope of the present study, as mentioned above, and will need to be

verified in future studies. Nevertheless, an increase of the nonplastic fines content of the

sands tested from 10 to 20% and from 10 to 30% increased the tensile strength of the cement-

treated silty sands by about 28 and 60%, respectively, irrespective of the amount of cement

and dry unit weight present in the mixture. A possible reason for the increase in qt with

increasing fines content is that specimens with larger amounts of fines have more contacts

points among particles (or higher coordination number). This allows better opportunity for

the Portland cement to develop more efficient bonds, increasing the tensile strength of the

mixture, as suggested by Chang and Woods (1992).

Durability

Figure 5(a) shows the variation of the accumulated loss of mass (ALM) with the number

of wet-dry cycles for compacted sands with 10, 20 and 30% of fines stabilized with 11%

Portland cement. All specimens shown in this figure were compacted with d of 16.5 kN/m3.

Increasing the amount of fines in the compacted sandy soil-cement mixture reduces the ALM

of the specimen after each one of the twelve wet-dry cycles [Fig. 5(a)]. The reason for the

reduction in ALM with the increase in the amount of fines is that the fabric of the specimens

with greater amounts of fines has a larger number of particle contacts. This provides better

opportunities for particle bonding following Portland cement hydration (Chang and Woods



1992), increasing mixture durability. In Figure 5(b) the variation of ALM with the number of

cycles is presented for the sand containing 30% of fines stabilized with 5, 8 and 11% Portland

cement and compacted with d of 16.5 kN/m3. Increasing the cement content of the

compacted sandy soil-cement mixtures reduces the ALM of the specimen after each one of the

twelve wet-dry cycles. Increasing the Portland cement content of the mixture leads to the

development of stronger cementitious bonds among the soil particles, thus reducing the ALM

of the specimens. Finally, Figure 5(c) shows that increasing the compacted dry unit weight of

the sand with 30% of fines stabilized with 11% of Portland cement from 15.5 to 16.5 kN/m3

reduces the ALM of specimens by about half. The larger the d, the smaller the porosity, thus

increasing the coordination number and potential for more effective bonding at the same

cement content.

Maximum Shear Modulus at Small Strains

The overall variation of the maximum shear modulus at small strains (G0) with the

number of wet-dry cycles is presented in Fig. 6. As these measurements were carried out on

the second set of (unbrushed) specimens, as described earlier in the experimental program,

Figs. 6(a), 6(b) and 6(c) refer to the same set of testing conditions discussed for Figures 5(a),

5(b) and 5(c) (i.e., analyses of the effects of fines content, cement content and dry unit

weight, respectively). Thus, these figures may be thought as mirror images of the trends

shown in Fig. 5, if the plots are flipped around the horizontal axis (i.e., the same factors that

would lead to an increase in ALM should cause a decrease in G0). Fig. 6(a) shows that

increasing the amount of fines of the compacted sandy soil-cement mixture increases G0 after

each one of the twelve wet-dry cycles. As discussed earlier, this increase in stiffness is due to

the higher coordination number (or number of particle contacts), which provides better

opportunity for bonding development following Portland cement hydration (Chang and

Woods 1992). Interestingly, for the mixture containing only 10% of fines, G0 increases only

up to the end of the first cycle, remaining constant afterwards. Conversely, the G0 of mixtures

containing 20 and 30% of fines continue to increase up to about the end of the sixth cycle,

remaining constant after that. A possible reason for this is that, for higher fines contents,

pozzolanic reactions amongst the Ca++

freed during Portland cement hydration and the excess

fines present in the mixture continues to occur up to a longer period (number of cycles). This

may also be due to the more effective bonding that can develop in sands containing fines with

higher coordination number/fines content as a result of the more efficiently packed fabric that



arises as the threshold fines content (Kuerbis et al. 1988) is approached. Figure 6(b) is

equivalent to Fig. 5(b) in that the effect of Portland cement content is accounted for the silty

sand with 30% of fines compacted with d of 16.5 kN/m3. Increasing the cement content of

the compacted silty sand proportionally increases G0 of the specimens after each one of the

twelve wet-dry cycles. The reason for this is that higher amounts of Portland cement develop

more bonds. However, G0 increases stop after the first, third and sixth wet-dry cycles for

cement contents equal to 5, 8 and 11%, respectively. Lastly, Figure 6(c) shows that for the

same compacted silty sand with 30% of fines, an increase in d from 15.5 to 16.5 kN/m3

increases G0 by about 50%. This is due to the lower porosity and higher coordination number

(thus particle contacts), which allow the Portland cement to develop more efficient bonds

(Chang and Woods 1992), as discussed earlier.

Post-Durability Tensile Strength

The variation of qt with the number of wet-dry cycles for select specimens of

compacted (d of 16.5 kN/m3) silty sands with 10 and 30 % of fines stabilized with 11%

Portland cement is presented in Fig. 7. Increasing the amount of fines from 10 to 30% for

these stabilized silty sands increases qt of the specimens tested after zero, six and twelve wet-

dry cycles. Similarly, to previous observations, the higher coordination number (i.e., particle

contacts) and the larger amount of fines present in the silty sand with 30% fines favourably

increase its qt, as shown by Chang and Woods (1992) through SEM microscopy on various

cemented sands. Oven-drying for 42 hours at 71o±2

oC throughout the drying stages of the

wetting-drying cycles may also help accelerate the chemical reactions induced by the

Portland cement increasing qt of the compacted silty sands with 10 and 30% of fines in early

cycles. Subsequent cycles (after 6th

) do not seem to continue to affect qt (Fig. 7), which is

consistent with stiffness trends shown in Fig. 6(a).

CONCLUSIONS

Based on the results of the present study, the following conclusions can be made:

Increasing the nonplastic fines content of the sands tested from 10 to 20% and from 10 to

30% increased the tensile strength of the cement-treated silty sands by about 28 and 60%,

respectively, irrespective of the cement content and dry unit weight of the mixture. This

might be due to the fact that specimens with larger amounts of fines have more contact



points amongst particles (i.e., higher coordination number), thus providing better

opportunities for the Portland cement to develop more efficient bonds;

The relationship [

( ) ]

is valid for all of the compacted cement-stabilized

silty sands tested (with fines content ranging from 10 to 30%), where the scalar k is

proportional to the fines content of the sand; a simpler, more fundamental form of this

relationship was shown to be equal to qt=K (Civ ⁄η), where K is directly related to the fines

content and/or coordination number of the mixture;

Increasing the fines content (from 10 to 30%) of the compacted cement-stabilized silty

sand specimens subjected to twelve wet-dry cycles reduced ALM and increased G0 and qt

of the sands;

The increase in cement content (from 5 to 11%) and d of the compacted cement-

stabilized silty sands proportionally decreased the ALM and increased the G0 of the

specimens after each one of the twelve wet-dry cycles;

When subjected to wetting-drying cycles, the G0 and qt of cement-stabilized silty sands

with 10 to 30% of fines increased up to the sixth cycle, remaining practically constant

after that;

Addition of rice husk ash fines to a uniform clean silica sand improved the overall

performance of the resulting Portland cement-stabilized silty sands subjected to hard

environmental conditions.

ACKNOWLEDGEMENTS

The authors wish to thank to PRONEX FAPERGS/CNPq (16/2551-0000469-2), CAPES-

PROEX and CNPq (INCT-REAGEO, Universal and Produtividade em Pesquisa) for funding

the research group.



NOTATIONS

ALM accumulated loss of mass (sum of dry mass lost due to brushing up to a certain cycle divided by

the initial mass of the specimen)

Cc coefficient of curvature

Civ volumetric cement content (cement volume divided by the total volume of specimen)

Cu coefficient of uniformity

D10 equivalent particle diameter (at which 10% of the material weight is finer)

D30 particle diameter at which 30% of the material weight is finer

D50 mean particle diameter (at which 50% of the material weight is finer)

D60 particle diameter at which 60% of the material weight is finer

G0 maximum shear modulus at small strains

qt splitting tensile strength

R2 coefficient of determination

η porosity

η/Civ porosity/cement index

d dry unit weight

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TABLE 1. Physical properties of the five materials used in this study.

Properties Sand (Sand + 10%fines) (Sand + 20%fines) (Sand + 30%fines) Fines

Plastic Index Non-

plastic Non-plastic Non-plastic Non-plastic

Non-

plastic

Specific gravity 2.65 2.56 2.52 2.44 2.20

Gravel (75 mm <

diameter < 4.75

mm) – (%)

0 0 0 0 0

Coarse sand

(4.75mm < diameter

< 2 mm) – (%)

0 0 0 0 0

Medium sand (2

mm < diameter <

0.425 mm) – (%)

0 0 0 0 0

Fine sand (0.075

mm < diameter <

0.425 mm) – (%)

97 87 77 67 0

Silt (0.002 mm <

diameter < 0.075

mm) – (%)

3 12 21 30 91

Clay (diameter <

0.002 mm) – (%) 0 1 2 3 9

D60 (mm) 0.16 0.15 0.14 0.12 0.03

Mean particle

diameter, D50 (mm) 0.14 0.13 0.12 0.10 0.023

D30 (mm) 0.11 0.10 0.08 0.06 0.019

Equivalent particle

diameter, D10 (mm) 0.08 0.07 0.02 0.016 0.006

Cc 0.9 1.0 2.8 2.0 2.2

Cu 1.9 2.2 7.3 7.7 4.3

USCS classification

(ASTM 2017)

Poorly

graded

sand

(SP)

Silty sand (SM) Silty sand (SM) Silty sand (SM) Silt

(ML)

TABLE 2. Characteristics of the specimens used in the durability tests.

Dry unit weight (kN/m³) 15.5 16.5

Fines content (%) 30 10, 20, 30

Cement content (%) 11 5, 8, 11



FIGURE CAPTIONS

FIGURE 1: Particle size distributions of the five samples used in this study.

FIGURE 2: Standard-energy compaction curve of Osório sand with 10% of fines.

FIGURE 3: (a) Splitting tensile strength (qt) versus η/(Civ)0.28

for 5, 8 and 11% of Portland

cement and γd = 14.5, 15.5 and 16.5 kN/m3; (b) Splitting tensile strength (qt) versus

η/Civ for 5, 8 and 11% of Portland cement and γd = 14.5, 15.5 and 16.5 kN/m3.

FIGURE 4: Parameter K versus fines content.

FIGURE 5: Accumulated loss of mass (ALM) versus number of wetting-drying cycles of

sands with (a) 10, 20 and 30% of fines, d = 16.5 kN/m3, and 11% of Portland cement,

(b) 30% of fines, d = 16.5 kN/m3 and 5, 8 and 11% of Portland cement, and (c) 30%

of fines, and d equal to 15.5 or 16.5 kN/m3 and 11% of Portland cement.

FIGURE 6: Maximum shear modulus at small strains (G0) versus number of wetting-drying

cycles for sands with (a) 10, 20 and 30% of fines, d = 16.5 kN/m3, and 11% of

Portland cement (including schematic particle model), (b) 30% of fines, d = 16.5

kN/m3 and 5, 8 and 11% of Portland cement and (c) 30% of fines, d equal to 15.5

kN/m3 or 16.5 kN/m

3 and 11% of Portland cement.

FIGURE 7: Variation of splitting tensile strength (qt) versus number of wetting-drying

cycles for sands with 10 and 30% of fines, d = 16.5 kN/m3, and 11% of Portland

cement.


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Accepted manuscript doi: 10.1680/jgeen.18 · 2020. 5. 22. · Accepted manuscript doi:...

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