Performance comparison of laboratory and field produced pervious concrete mixtures

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  • ddwille,

    Keywords:Pervious concretePerformanceEvaluationLaboratory mixesField mixes

    conng lmix

    cores were evaluated and compared through laboratory performance tests, including air voids, perme-

    te (PCconsisd littl

    has attracted more and more attention in concrete industry dueto the increased awareness of environmental protection. Many lab-oratory and eld studies have been conducted to investigate intovarious aspects of pervious concrete [14,912]. Researchers atthe National Concrete Pavement Technology Center (NCPTC) devel-oped the mix proportions for pervious concrete in cold weather cli-mates [1,9,10]. Delatte et al. [11,12] veried that PCPC can perform

    ditional concrete may not be suitable for pervious concrete.Many studies revealed that unlike conventional concrete, the

    performance of pervious concrete is highly dependent on both con-crete materials and construction techniques [1,11,12]. The focus ofpervious concrete technology is the balance of permeability andmechanical properties as well as durability. If the mixture is toowet and easy to compact, the voids will be clogged and the perme-ability will be compromised. However, if the mixture is too dry andhard for compaction, the pervious concrete pavement will be weakand vulnerable to various types of distress. Although specications

    Corresponding author. Tel. +1 865 974 2608; fax: +1 865 974 2669.

    Construction and Building Materials 25 (2011) 31873192

    Contents lists availab

    B

    evE-mail address: xshu@utk.edu (X. Shu).Use of uniform coarse aggregate and little or no ne aggregategives PCPC much higher porosity and permeability than conven-tional concrete, which enables quick drainage of stormwater [14]. Therefore, PCPC is a very effective stormwater management toolto reduce the volume of stormwater runoff and the concentrationof pollutants [5]. In addition, pervious concrete can also reduce ur-ban heat island effect and acoustic noise [6,7].

    Since it was rst introduced into the United States in the mid1970s, pervious concrete has been used in many applications forover 30 years [8]. During the last few years, pervious concrete

    lected aggregates, adding ne aggregates and organic intensiers,and optimizing mix proportion to improve the strength and abra-sion resistance of PCPC. Kevern [3] showed that the addition ofpolymer (styrene butadiene rubber, SBR) signicantly improvesworkability, strength, and freezethaw resistance of pervious con-crete while maintaining its high porosity and permeability. Huanget al. [13] improved the strength properties of pervious concretethrough polymer modication. Kevern et al. [14] identied thatcoarse aggregate type has a direct effect on the freezethaw dura-bility of pervious concrete and certain aggregates approved for tra-1. Introduction

    Portland cement pervious concretally friendly paving material. PCPCwater, uniform coarse aggregate, an0950-0618/$ - see front matter Published by Elsevierdoi:10.1016/j.conbuildmat.2011.03.002ability, compressive and split tensile strengths, as well as Cantabro and freezethaw durability tests.Two types of coarse aggregate, limestone and granite, with two gradings, No. 8 and No. 89 specied inASTM C33, were used to produce the mixtures. Latex, air-entraining admixture (AEA), and high rangewater reducer (HRWR) were also added to improve the overall performance of pervious concrete. Theresults indicated that the mixtures made with limestone and latex had lower porosity and permeability,as well as higher strength and abrasion resistance than other mixtures. Even for pervious concrete, theaddition of AEA could still help to improve the freezethaw resistance. The comparison between labora-tory and eld mixtures showed that a properly designed and laboratory veried pervious concrete mix-ture could meet the requirements of permeability, strength, and durability performance in the eld.

    Published by Elsevier Ltd.

    PC) is an environmen-ts of portland cement,e or no ne aggregate.

    well in freezethaw environments based on the results from eldvisual inspection and laboratory performance tests.

    Due to its high porosity, pervious concrete generally has signif-icantly lower strength and durability properties than conventionalconcrete. Yang and Jiang [6] suggested using appropriately-se-Available online 26 March 2011for laboratory tests to ensure the anticipated performance of laboratory designed pervious concrete. Inthis study, the performance of laboratory and eld produced pervious concrete mixtures as well as eldPerformance comparison of laboratory anconcrete mixtures

    Xiang Shu , Baoshan Huang, Hao Wu, Qiao Dong, EDepartment of Civil and Environmental Engineering, The University of Tennessee, Knoxv

    a r t i c l e i n f o

    Article history:Received 29 October 2010Received in revised form 18 February 2011Accepted 1 March 2011

    a b s t r a c t

    Portland cement perviousincreasingly used in parkitions are available for the

    Construction and

    journal homepage: www.elsLtd.eld produced pervious

    in G. BurdetteTN 37996, USA

    crete (PCPC) is an environmentally friendly paving material that has beenots as well as low volume and low speed pavements. Although specica-design and construction of pervious concrete, there still remains a need

    le at ScienceDirect

    uilding Materials

    ier .com/locate /conbui ldmat

  • are available for the mix design and construction of pervious con-crete, there still remains a need for laboratory tests to ensure theanticipated performance of laboratory designed pervious concrete.This study presents the comparison among laboratory and eldproduced mixtures as well as eld cores in terms of air voids, per-meability, strength, Cantabro loss, and freezethaw durability. Theresults showed that a properly designed and laboratory veriedpervious concrete mixture could meet the requirements of perme-ability, strength, and durability performance in the eld.

    2. Research objective and scope

    The objective of the present study was to evaluate and compare

    vious concrete mixtures. To improve the overall performance of

    paction. The specimens were cured in a standard moisture curing

    men dimension reect its surface texture and true volume. There-

    developed by Huang et al. [15] for porous asphalt mixtures (similar

    The split tensile strength test was conducted on150 mm 63.5 mm cylindrical specimens with an MTS machine

    Field mixtures

    Mix. no. L1 L2 L3 L4 L5 F1 F2 F3

    390 390 360 360 350140 100 110 95 90LS LS LS LS LSNo. 89 No. 89 No. 8 No. 8 No. 81440 1440 1440 1440 1490109 109 100 100 100 39 36 36 0.91160 1160 470 940 470390 390 690 690 700500 500 500 500 500

    Mixture F1

    Mixture F2

    Mixture F3

    3188 X. Shu et al. / Construction and Building Materials 25 (2011) 31873192Cement 380 390 390Water 100 140 100Coarse aggregate GR LS LS

    No. 89 No. 89 No. 891420 1440 1440

    Fine aggregate 107 109 109Latex 38 39Fiber HRWR (ml) 1150 1160 1160AEA (ml) VMA (ml) 500 500 500chamber until the days of testing. The pervious concrete pavementwas compacted with manual rollers (Fig. 1). Field cores 150 mm. indiameter were extracted from the pervious concrete pavement3 weeks after construction and transported to the University ofTennessee for laboratory testing.

    Table 1Mix. proportions for laboratory and eld produced mixtures (kg/m3).

    Mix. type Laboratory mixturesPCPC, ne aggregate, latex, monolament polypropylene ber,high range water reducer (HRWR), air-entraining admixture(AEA), and viscosity-modifying admixture (VMA) were added tothe mixtures. The mix proportions for the laboratory and eldproduced pervious concrete mixtures in this study are based on alaboratory mix design presented in Table 1.

    3.2. Sample preparation

    The laboratory produced pervious concrete mixtures weremixed using a rotating-drum mixer. The eld mixtures were col-lected in the middle of placement from a truck mixer at a readymix concrete plant (the eld project was in the plant). Laboratorytest specimens were made by applying standard rodding for com-the laboratory and eld produced pervious concrete mixtures aswell as eld cores through laboratory performance testing. The lab-oratory testing employed for the evaluation included the tests forair voids, permeability, compressive and split tensile strengths,Cantabro loss, and freezethaw durability.

    3. Laboratory experiment

    3.1. Materials

    Ordinary Type I Portland cement was used in the mixtures. Twocoarse aggregates, limestone and granite, with two gradings, No.89 and No. 8 specied in ASTM C33, were used to produce the per-Note: GR granite, LS limestone, HRWR high range water reducer, AEA air-entraininASTM C33.to pervious concrete in permeability) was used to obtain the pseu-do-coefcient of permeability of pervious concrete mixtures. De-tailed information about the test and the analysis method can befound in Huang et al. [13,15]. 150 mm 75 mm cylindrical speci-mens were used in this test.

    3.5. Compressive and split tensile strength tests

    The compressive strength test was conducted at 28 days inaccordance with ASTM C39. An INSTRON testing machine was usedto perform this test on 100 mm 200 mm cylindrical specimens.fore, a vacuum package sealing device, CoreLok (Fig. 2), commonlyused to measure the specic gravity and air void content for as-phalt mixtures, was used in this study to obtain the air voids ofpervious concrete specimens. This test was conducted by followingthe ASTM D7063 procedures.

    3.4. Permeability test

    Due to high porosity and permeability, Darcys law for laminarow is not applicable to pervious concrete. In this study, a fallinghead permeability measurement device (Fig. 3) and a method3.3. Air voids test

    Since pervious concrete has a relatively high porosity, it is notsuitable to use the submerged weight measurement to obtain itsbulk volume. Neither does geometrical measurement of a speci-

    Fig. 1. Pervious concrete eld project.g admixture, VMA viscosity modifying admixture, No. 8 and No. 89 are specied in

  • ildingFig. 2. CoreLok for air voids test.

    X. Shu et al. / Construction and Buin accordance with ASTM C496. The vertical load was continuouslyrecorded, and split tensile strength was computed as follows:

    St 2PultptD 1

    where St = split tensile strength, Pult = peak load, t = thickness ofspecimen, and D = diameter of the specimen.

    3.6. Cantabro Test

    The Cantabro test was initially used for testing the abrasionresistance of asphalt open-graded friction course (OGFC) a por-ous asphalt mixture [16]. This test is conducted with the Los Ange-les (LA) abrasion machine (ASTM C 131) without the steel ballcharges. The weight loss after the test (called the Cantabro loss)is calculated in percentage as follows:

    Cantabro Loss W1 W2W1

    100 2

    where Cantabro loss = weight loss in percentage, W1 = initial sam-ple weight, and W2 = nal sample weight.

    Fig. 3. Permeability test setup (after [13]).In this study, the Cantabro test was used to characterize theabrasion resistance of pervious concrete specimens.150 mm 101.6 mm cylindrical specimens were used in the test.

    3.7. Freezethaw test

    The freezethaw test was conducted to determine the freezethaw resistance of pervious concrete mixtures using procedure Aof ASTM C666, in which specimens were subjected to continuousfreezing and thawing in the saturated condition. Relative dynamicmodulus (RDM) and mass loss were used to characterize thefreezethaw durability of pervious concrete. The durability factoris calculated as follows [14]:

    DF PNM

    3

    where P = relative dynamic modulus of elasticity or relative mass atN cycles in percent, N = number of cycles at which P reaches thespecied minimum value for discontinuing the test or the specicnumber of cycles at which the exposure is to be terminated, which-ever is less. The criteria for P were 60% for RDM or 3%, 5%, or 15%when calculated for mass, and M = specied number of cycles atwhich the exposure is to be terminated, 300 cycles.

    4. Results and discussion

    4.1. Air voids

    Fig. 4 shows the air voids results for the laboratory and eldproduced pervious concrete mixtures. For the laboratory mixtures,the mixture made with limestone and latex (L3) exhibited lowerair voids than that with granite (L1). The air void content of Mix-ture L3 (made with latex) was also lower than that without latex(L2), which means that incorporation of latex to pervious concretewould lower the mixtures porosity. For the eld mixtures, withthe decrease in water content (Mixture F3 < F2 < F1), the eld mix-tures showed an increase in air voids (Mixture F3 > F2 > F1). This isdue to the fact that Mixture F1 was too wet and its air voids wereeither lled with or blocked by cement paste/mortar, whereas Mix-ture F3 was too dry and hard to compact. It can be seen from Fig. 4that the eld cores extracted from the previous concrete pavementshowed higher air voids than the test specimens made with eldmixtures, which could be attributed to the difference in compac-tion method and compaction effort.

    4.2. Permeability

    The permeability results of the pervious concrete mixtures areshown in Fig. 5. It is evident that the permeability results wereconsistent with the air voids results because air voids and perme-ability are highly correlated. The laboratory mixture made withlimestone and latex (L3) showed lower permeability than that withgranite (L1) or the mixture without latex (L2). The ranking of theeld mixtures in terms of permeability was F3 > F2 > F1 due totheir difference in air voids. The eld cores also showed higher per-meability than the test specimens made with eld mixtures.

    4.3. Compressive and split tensile strengths

    Figs. 6 and 7 compare the compressive and split tensilestrengths of laboratory and plant produced pervious concrete mix-tures. The mixtures showed very similar trends in compressive andsplit tensile strength. The laboratory mixture with limestone and

    Materials 25 (2011) 31873192 3189latex (L3) had higher compressive and split tensile strengths thanthe mixture with granite (L1) or the mixture made without latex(L2). Two eld mixtures (F1 and F2) had higher compressive and

  • ldin3190 X. Shu et al. / Construction and Buisplit tensile strengths than the laboratory mixtures. The third eldmixture, F3, was too dry and hard to compact, and thus exhibited

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    g Materials 25 (2011) 31873192lower strengths than the laboratory mixtures. As expected, theeld cores exhibited lower split tensile strength than the test spec-imens made with eld mixtures due to their higher porosity.

    4.4. Cantabro loss

    The Cantabro loss resul...

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