Effects of the curing methods on the process of plastic shrinkage of self compacting concrete in Vietnam

This paper presents the experimental results of researching on plastic shrinkage (plastic deformation) and the effect of curing methods on the process of plastic shrinkage at the early stages when self-compacting concrete (SCC) starts setting and develops the strength. The experiments were carried out in two typical climatic conditions in Vietnam which are humid and dry.

Journal of Science and Technology in Civil Engineering NUCE 2018 12 (5): 39–50 EFFECTS OF THE CURING METHODS ON THE PROCESS OF PLASTIC SHRINKAGE OF SELF-COMPACTING CONCRETE IN VIETNAM Nguyen Hung Cuonga,∗, Luu Van Thuca , Tran Hong Haia , Pham Nguyen Van Phuonga a Faculty of Construction Economics and Management, National University of Civil Engineering, 55 Giai Phong road, Hai Ba Trung district, Hanoi, Vietnam Article history: Received 09 May 2018, Revised 06 August 2018, Accepted 24 August 2018 Abstract This paper presents the experimental results of researching on plastic shrinkage (plastic deformation) and the effect of curing methods on the process of plastic shrinkage at the early stages when self-compacting concrete (SCC) starts setting and develops the strength The experiments were carried out in two typical climatic conditions in Vietnam which are humid and dry The experiments were conducted with two typical water/powder ratios of 0.3 and 0.35 and four cases of curing methods which are nylon membrane, watering, no-curing and soaking in water (the standard condition) Besides, the influences of plastic shrinkage at the early stages on strength development and occurrence of surface cracking of SCC were also investigated The conclusions were drawn about the plastic deformation process and the curing method that might minimize plastic shrinkage of SCC, control surface cracking early, and ensure the quality and strength of SCC in the hot and humid climatic condition of Vietnam Keywords: plastic shrinkage; self-compacting concrete; hot and humid climate; hardening process https://doi.org/10.31814/stce.nuce2018-12(5)-05 c 2018 National University of Civil Engineering Introduction Plastic shrinkage is a common physical process that takes place in the early stage when concrete starts setting and hardening, especially for members with large exposed surfaces Plastic shrinkage process is also an important physical process that causes cracks in the early stage and directly affects the development of concrete strength According to [1], when the evaporation rate of water on the surface of the newly poured concrete is quicker than that of the excess water from the cement hydration, the concrete surface will shrink Due to the restraint of concrete under drying surfaces, tensile stress develops in weak areas, which forms cracks According to [2, 3], plastic shrinkage process occurs because the water drainage out of the pore system causing negative pressure leads to the change of cement volume while the concrete is not strong enough to resist the tensile stress induced by plastic shrinkage According to [3, 4], physical processes occur immediately after concrete placement, which include: dehydration (evaporation), plastic deformation (plastic shrinkage), displacement and change of water and vapor pressure in concrete, stress formation inside, cracking, capillary, pores in concrete These processes are interrelated, interdependent, and decisive to the initial structural formation of concrete as well as to the physical-mechanical properties of concrete ∗ Corresponding author E-mail address: cuongnguyen.dhxdhn@gmail.com (Cuong, N H.) 39 Cuong, N H et al / Journal of Science and Technology in Civil Engineering According to [5], when concrete is in a flexible state, the dehydration facilitates shrinkage deformation In this state, the deformation does not lead to the formation of cracking concrete structures, whereas the movement of aggregate particles makes concrete solid, porosity and pore size within concrete smaller At the same time, the excessive water in concrete evaporates, which reduces the risk of forming pores and capillary voids in concrete According to [6], if the water evaporation of concrete at the early stage of hardening is from 30% to 35% of the total, it will not adversely affect the structure and quality of concrete If the dehydration happens quickly and massively, it will promote plastic deformation to reach the maximum value quickly and to develop continuously during the subsequent stages of concrete (solid phase) As a result, cracks in concrete members will be created According to [7], with remarkable advantages in terms of workability, quality and strength, selfcompacting concrete (SCC) has been widely used in the construction industry around the world and applied in super high rise building projects in Vietnam Due to being more effective in terms of technology and economics, SCC is predicted as an indispensable trend in concrete construction in Vietnam [8] SCC is basically not much different from traditional concrete However, the characteristics of less coarse aggregate content, powder increase (using fly ash and blast furnace) and specially the use of more additives (in particular superplasticizers) make the hydration and hardening processes of SCC much different from traditional concrete [4, 7] According to [4], the self-compacting property of SCC is obtained by using fine fillers and low water/powder ratio, minimizing coarse aggregate content and adding high superplasticizers According to [9], the important factor affecting the processes of hydration and formation of cement structure of SCC is the amount of water available in the mixture and the bond type of water with the solid phase and new substances formed during the hydration According to [10], the presence of fly ash improves the microstructure of concrete, making it denser Nevertheless, it also makes the microstructure grow slower Unresponsive fly ash particles contribute to the microstructure development of the cement because it acts as super-fine aggregate in the cement paste There have been many studies relating to plastic shrinkage of SCC According to [11], fillers not have much significant influence on autogenous shrinkage of SCC Effect of additives on plastic shrinkage is studied in [12] Its finding shows that additives can reduce the risk of cracking due to plastic shrinkage if shrinkage reducing additives or paraffin oil-based curing agent are used Another research points out that curing time is important in limiting plastic shrinkage at early ages, and the total long-term shrinkage of cured concrete has higher than that of uncured concrete [13] According to [14], the cracking age depends on the water/powder ratio; fly ash and limestone powder increase the cracking age of concrete; the shrinkage rate is greater when concrete is exposed to dry conditions; and the longer curing time leads to a shorter cracking age However, these studies were conducted at climatic conditions different from that of Vietnam or in laboratories with temperature-humidity conditions controlled Vietnam has a hot and humid climate The means of relative humidity and temperature are normally high The periods of sun and rain are cyclical and long Many long hot cycles often happen in the summer season for the North and Central, and in the rainy season for the South During that cycles, solar radiation can reach 500 kcal/m2 hour to 900 kcal/m2 hour, daytime temperatures can be 35◦ C to 50◦ C, and humidity can be low about 40% to 65% Winter in the North and Central basically has a dry climate with dry monsoon The average temperature is normally low, about 15◦ C to 30◦ C The relative humidity is low, often from 40% to 65% These characteristics speed up the process of water evaporation Additionally, the variations of temperature and humidity in the day are high, about 10◦ C to 15◦ C and 45% to 50% respectively [3, 15] These adverse weather conditions may have great 40 tionplastic and the thedeformation occurrence and of early early cracks is is also also analyzed Finally, the paper proposes proposes the occurrence of early cracksFinally, is also the analyzed Finally, the tion and occurrence of cracks analyzed paper ive curing method to minimize plastic deformation of SCC and toanalyzed ensure the quality ic and the occurrence of cracks isplastic also analyzed Finally, the paper prop plastic deformation and the occurrence of early cracks isand alsoto Finally, the pa the most effective curing method to minimize deformation of SCC and to ens ticdeformation deformation andto the occurrence of early early cracks is also analyzed Finally, the paper propo ve curing method minimize plastic deformation of SCC ensure the quality most effective curing method to minimize plastic deformation of SCC SCC and and to ensure ensure theensu qu SCCand in the the Vietnamses hot and humidtoclimate climate the most effective curing method minimize plastic of SCC and to strength of SCC in the Vietnamses hot and humiddeformation climate most effective curing method to minimize plastic deformation of to the qua SCC in Vietnamses hot and humid strength in Vietnamses hot and humid climate and of strength ofthe SCC inN.the Vietnamses hotandand humid climate strength ofSCC SCCprocess in the Vietnamses and humid climate Cuong, H et al / hot Journal of Science Technology in Civil Engineering nd experiment Materials and experiment process d experiment process aterials and process Materials and experiment process impacts on the water evaporation as well as the formation of internal structure of SCC Materials andexperiment experiment processprocess nd experiment equipment 2.1 Materials and experiment equipment Currently, there are no experimental studies on the plastic deformation process at the early hardnd experiment equipment Materials and experiment 2.1 Materials and equipment Materials and experiment equipment ening stages of SCCexperiment inequipment the hot humid climate of cement Vietnam The paperof aims i) to investigate the plastic used in the experiments include: portland PC40 Vincem But Son; yellow Materials used in the experiments include: portland cement PC40 ofyellow Vincem B used in the experiments include: portland cement PC40 of Vincem But Son; deformation process in the early hardening stages of SCC and ii) to examine the effect of curing Materials used in the experiments include: portland cement PC40 of Vincem But Son; ye Materials used in the experiments include: portland cement PC40 of Vincem Bu Materials used inmix the experiments cement PC40 of Vincem But River with theRed modulus size ofthe 2.76; crushed stone with the maximum diameter of yell sand from River with modulus size of 2.76; crushed stone the maximu methods and design on the plastic deformation process The correlation between thewith plastic de- Son; River with the modulus size of 2.76; crushed stone with the maximum diameter of the modulus 3crushed from Red River with the size ofPha stone with thethermal maximum diamete sand from Red River with size 2.76; crushed stone with the maximum dspecific from Red River with the modulus modulus stone with the maximum diamete gravity of 2.67g/m ; offlyearly ash of Lai thermal power with thethe type of F with formation and the occurrence cracks is2.76; also analyzed Finally, the paper proposes most 10mm and the specific of 2.67g/m ;offly ash ofpower Pha Lai power 3gravity specific gravity of 2.67g/m ; fly ash thermal with the type of Fwith 3of Pha Lai m the specific gravity 2.67g/m ;2.67g/m fly ash ;of Lai thermal power with thethe type effective curing method toof minimize plastic deformation of SCC and tomodified ensure andon strength 10mm andASTM theBiFi-HV298 specific gravity ofBiFi-HV298 fly ash of Pha the Laiquality thermal power mm and the specific gravity of 2.67g/m Pha Lai thermal power with the type M and C618 standard; superplasticizer based on polymer with following C618 standard; superplasticizer based modified poo M C618 standard; BiFi-HV298 superplasticizer based on modified polymer with the of SCC in the Vietnamese hot and humid climate wing ASTM C618 standard; BiFi-HV298 based on modified polymer with following ASTM BiFi-HV298 superplasticizer based onCuLminal modified poly ASTM C618 standard; BiFi-HV298 based on modified polymer with yowing of specific 1.05 equivalent toC618 the Gstandard; type following ASTM C-494 standard; and gravity of 1.05G equivalent tosuperplasticizer theASTM G type following ASTM C-494 standard; of 1.05 equivalent to the type following C-494 standard; and CuLminal ific gravity of 1.05 equivalent to type ASTM C-494 standard; and CuLm CuLm specific gravity of 1.05 equivalent to thefollowing G (Fig.1) type following ASTM C-494 standard; a gravity of 1.05modifying equivalent to the Gmodifying ASTM C-494 standard; and 0cific type as 2.viscosity admixture (VMA) with MHPC400 type as viscosity admixture (VMA) (Fig.1) Materialsmodifying and experiment process type as viscosity admixture (VMA) (Fig.1) type modifying admixtureadmixture (VMA) (Fig.1) (Fig.1) with MHPC400 type as viscosity modifying (VMA) (Fig.1) hMHPC400 MHPC400 type as as viscosity viscosity modifying riments were conducted with two water/powder ratios which are 0.3ratios and which 0.35 The The experiments were conducted with two water/powder are 0.3 2.1 Materials and experiment equipment riments were conducted with two water/powder ratios which are 0.3 and 0.35 The The experiments were conducted with two water/powder ratios which are 0.3 and 0.35 The experiments were conducted water/powder ratios which are 0.3 and 0.35 The experiments were conducted with two water/powder ratios which are 0.3 ed inmix the designs experiments are chosen based onare practical experience in Japan andyellow Europe used in the experiments chosen based practical in JapaT Materials usedare in the experiments include: portland cement PC40on of Vincem But experience Son; ed in the experiments chosen based on practical experience in Japan and Europe designs used inSociety the experiments onand practical experience in and Eur designs used in the experiments are chosen based practical experience in Japan Japan and Eu mixJapan designs used inthe the experiments are chosen based onEuropean practical experience inofJapa sand from Red River the modulus size of crushed stone with the maximum diameter of by the ofwith Civil Engineers (JSCE) the Federation recommended by Japan Society of2.76; Civil Engineers (JSCE) and the European by the Japan Society of Civil Engineers (JSCE) and the European Federation of ommended by the the the Japan Society (JSCE) and the European Federation mmended Japan Society Civil Engineers (JSCE) and thewith European recommended by the Japan Society Engineers (JSCE) and the ofEuropean F 10by mm and specific gravity ofof 2.67 g/m ;of fly Civil ash of of Pha Lai thermal power the type FFederatio ciations Representing producers and applicators specialist building products for National Associations Representing producers and applicators of specialist buildin iations Representing producers and applicators ofand specialist building products for following ASTM C618 standard; BiFi-HV298 superplasticizer based on modified polymer with theproducts ional Associations Representing applicators of specialist building onal Associations Representing producers and used applicators of specialist building products National Associations Representing applicators of specialist building ARC) The theory of absolute volume isproducers also to C-494 determine the mix designs asthe Concrete (EFNARC) The theory of absolute volume is also used to determine specific gravity of 1.05 equivalent to the G type following ASTM standard; and CuLminal with ARC) The theory of absolute isabsolute also used to determine the mix designs as creteConcrete (EFNARC) The theory ofvolume absolute volume isvolume also used to determine the mix designs crete (EFNARC) The theory of used to determine the mix design (EFNARC) The theory of is also used to determine the m shown MHPC400 type as viscosity modifying admixture (VMA) (Fig 1) in Tab.1 wnininshown Tab.1.in Tab.1 wn Tab.1 (a) Cement ement Cement a) a) Cement Cement ement a)a)Cement (d) Crushed stone Fly ash (c) Yellowc) sand b) Fly ashb)(b)Fly sand b)Fly Flyash ash c) Yellow c) Yellow Fly ash Yellow ashb) c)sand Yellowc)sand sand Yellow b) Fly ashb) c) Yellow (e) Super-plasticizer (f) VMA Crushed stone stone e) Super-plasticizer Super-plasticizer hed d) stone e) Super-plasticizer d) Crushed stone e)Super-plasticizer Super-plasticizer f) VMA f)f)VMA VM Crushed e) VMA f)f)VM d) stone Crushed e) hedd) stone e) Super-plasticizer f) VMA Figure Materials used in the experiments Figure 1 Figure Materials used in the experiments Figure Materials used in1 experiments 1.the Materials used theexperiments experiments Figure Materials used in the experiments Figure Materials used ininthe Figure Materials used in the experiments The experiments were1 conducted withdesign two water/powder ratiosexperiments which are 0.3 and 0.35 The mix Table The mix used in the Table mix1.design used inmix the Table 1.design The mix design used the experiments Table The used in the experiments Table The design used ininthe experiments designs used1.inThe the experiments aremix chosen based onexperiments practical experience in Japan and Europe recTable The mix design used in the experiments ommended by the Japan Society of Civil (JSCE) and the European SuperFederation of National Cement FlyEngineers Stone Cement Fly Stone Super-Stone Cement Fly Stone SuperCement Fly Stone SuperMix design Sand VMA Cement Fly SuperAssociations Representing producers and applicators of specialist building products for Concrete (EFgnMix design Sand VMA Water Wa Mix design PC40 Sand V Sand VMA Wa Cement Fly Stone Superash (0.5x1) plasticizer Sand VM ash volume (0.5x1) plasticizer PC40 ash (0.5x1) plasticizer ash (0.5x1) plasticizer NARC).PC40 The theory ofPC40 absolute is also used to determine the mix (0.5x1) designs as VMA shown in Table gn Sand Water PC40 ash plasticizer PC40 ash plasticizer (g) (kg) (kg) (0.5x1) (kg) (kg) (g) 41 (kg) (kg) (kg) (kg) (kg) (kg (kg) (kg) (kg) (kg)(g) (g) (g) (g) (kg) (kg) (kg) (kg) (g) (kg) (g) (k( (kg) (g (kg) (kg) (kg) (kg) (g) (g) (kg) Water/Powder=0.3 30.69 10.2 53.9 50.82 388.2 12.0 12 er=0.3 Water/Powder=0.3 30.69 10.2 30.69 53.9 50.82 12.0 388.2 12.27 121 30.69 10.2 53.9 53.9388.250.82 50.82 388.2 Water/Powder=0.3 30.69 10.2 53.9 50.82 388.2 12.0 10.2 er=0.3 30.69 10.2 53.9 50.82 388.2 259.2 12.0 12.27 12 Water/Powder =0.35 27.6 9.45 53.9 50.82 12.0 Cuong, N H et al / Journal of Science and Technology in Civil Engineering Table The mix design used in the experiments Mix design Water/Powder = 0.3 Water/Powder = 0.35 Cement PC40 (kg) Fly ash (kg) 30.69 27.6 10.2 9.45 (kg) Stone (0.5 × 1) (kg) Superplasticizer (g) 53.9 53.9 50.82 50.82 388.2 259.2 Sand VMA Water (g) (kg) 12.0 12.0 12.27 12.99 The specimen size is 10 × 10 × 30 cm The longest side (30 cm) is used to measure plastic deformation of SCC specimens 2.2 Experiment conditions The experiments were conducted in January and February in Vinh Tuy ward, Hai Ba Trung district, Hanoi, with the climatic conditions of the North of Vietnam 2.3 Experiment process After weighing in accordance with the mix design, the aggregates were added to the mixer and mixed following the defined process and corresponding time in Table and Fig The plastic deformation was measured by using two strain gauges with the graduation of 0.002 mm These gauges were placed at the both ends of the specimens At each end, there was a 0.5 mm-thin steel plate with the size of 9.5 cm × 9.5 cm These plates were attached to the concrete by welding (Fig 3) The steel plate were embedded in the measurement form before placing concrete to make sure that its outer surface is beyond the outer edge of the specimen The tip of the probe is placed in contact with the outside of the plate and adjusted to the center When the concrete shrinks or expands, the steel plate moves along with the movement of the probe The measurement was done once per hour during the first hours to hours, and measured again at the 22nd to 24th hours since the time of concrete placement to investigate plastic deformation at longer intervals Table Concrete mixing process of the experiment Step Content Adding 50% (water + additives) + 100% stone Adding gradually (cement + powder), and mixing the materials evenly Adding remaining materials (sand + water + additives), and mixing all materials evenly Stopping and waiting Mixing again Discharging the mixture Time minute 1.5 minutes minutes minutes minutes Experimental results The experiments were conducted with two different mix designs and in two typical climate conditions which are humid condition and dry condition Three experiments were carried out, including: 42 4 5 Stopping and waiting and waiting Stopping andStopping waiting 5 Mixing Mixing again Mixing again Mixing againagain 6 Discharging Discharging the the mixture Discharging Discharging mixture the mixture the mixture minutes minutes minutes 5minutes minutes minutes minutes Cuong, N H et al / Journal of Science and Technology in Civil Engineering (a) Adding aggregates (b) Adding additives Mixing (d) Discharging plastic Adding b) Adding plastic a) Adding b) Adding additives c)(c)Mixing d) Discharging plasticplastic a) aggregates Adding aggregates b) Adding additivesc) Mixing c) Mixingd) Discharging d) Discharging a)aggregates Adding aggregates b) additives Adding additives c) Mixing d) Discharging concrete concrete concrete plastic concrete concrete measured by using two strain gauges with the graduation of 0.002mm These gauges were placed at the both ends of the specimens At each end, there was a 0.5mm-thin steel plate with the size of 9.5x9.5cm These plates were attached to the concrete by welding (Fig.2) The steel plate were embedded in the measurement form before placing concrete to make sure that its outer surface is beyond the outer edge of the specimen The tip of the probe is placed in contact with the outside of Spreading plastic (f) Curing (g) Removing the form (h) Installing gauges and e) Spreading plastic h) Installing gauges e) Spreading plastic h) gauges e) (e) Spreading plastic h) Installing Installing gauges the plate and adjusted to the center When the concrete shrinks or expands, the plate moves along e) Spreading plastic h) steel Installing gauges concrete into the measuring plastic concrete into the f) Curing g) Removing the the form andand measuring plastic concrete into the f) Curing g) Removing form measuring plastic concrete into the f) Curing g) Removing the form and measuring plastic with into themeasurement movement of the probe The measurement was done once per hourand during the first plastic 7÷8 hours, concrete the f) Curing g) Removing the form measuring form deformation measurement form deformation measurement form deformation measurement deformation and measured at the 22nd -24th hours since the time of concrete placementdeformation to investigate plastic measurement form againform Figure The mixing process and the measurement of plastic deformation of SCC specimens Figure The process and the measurement of plastic deformation of SCC specimens Figure 3.mixing The mixing process andand thethe measurement ofofplastic deformation of specimens Figure The mixing process measurement plastic deformation of SCC specimens deformation at3.longer intervals Figure The mixing process and the measurement of plastic deformation of SCC specimens Experimental results Experimental results Experimental results Experimental results The experiments were were conducted with with two different mixmix designs andand in two typical climate The The experiments conducted two in typical climate experiments were conducted with twodifferent different mixdesigns designs and in two typical climate The experiments were conducted with two different mix designs and in two typical climate onditions which are humid condition and dry condition Three experiments were carried out, conditions which are are humid condition carried out, conditions which humid conditionand anddry drycondition condition.Three Three experiments experiments were carried out, ncluding: Experiment with the water/power ratio of 0.35 in humid condition; Experiment with onditions which are humid condition and dry condition Three experiments were carried out, including: Experiment with the water/power ratio of 0.35 in humid condition; Experiment with including: Experiment with the water/power ratio of 0.35 in humid condition; Experiment with he water/power ratio 1of 0.3ofin humid condition; Experiment with the water/power ratio 0.35 in in ncluding: Experiment with ratio of 0.35 in humid Experiment of with the water/power ratio 0.3 in humid condition; Experiment 33condition; with ratio of 0.35 the water/power ratiothe ofwater/power 0.3 in humid condition; Experiment withthe thewater/power water/power ratio of 0.35 in ry water/power condition Three curing werewere carried out for 3each experiment to examine effect of of he ratio Three of 0.3 inmethods humid condition; Experiment with theexperiment water/power ofthe 0.35 ineffect dry condition curing methods carried examine the effect dry condition Three curing methods were carriedout outfor foreach each experiment to toratio examine the of uring method on plastic deformation of at the early hardening stages, curing method on plastic deformation process of stages, including: no ry condition Three curing wereprocess carried outSCC for each to examine the including: effect of nono curing method on methods plastic deformation process ofSCC SCCatexperiment atthe theearly earlyhardening hardening stages, including: uringcuring - KBD- KBD (free evaporation of water under the influence of the natural environment); watering - (free evaporation of water under the influence of the natural environment); watering uring method on- plastic deformation process of SCC early hardening stages, including: watering no curing KBD (free evaporation of water under at thethe influence of the natural environment); N (watering the specimens every one hour), nylon membrane - BNL (dry curing method, covering TN (watering the specimens every one hour), nylon membrane BNL (dry curing method, covering TN (free (watering the specimens every onethe hour), nylon of membrane - BNL (dry curing watering method, covering uring - KBD evaporation of water under influence the natural environment); he specimen surfaces by nylon to minimize the water evaporation) At the same time, the plastic the specimen surfaces by nylon to minimize the water evaporation) At the same time, the plastic specimen surfaces nylon to minimize the water At the same the plastic N (watering the specimens every one hour), nylon - evaporation) BNL (dry method, covering oncrete ofthe mixing batches wasby also collected for membrane making specimens thatcuring were used fortime, compression concrete of mixing was also collected forfor making specimens that were used compression concrete of mixing batches was also collected makingand specimens that were used for compression he surfaces by batches nylon to minimize the water evaporation) At the same time, thefor plastic est specimen in order to determine the effect the curing method plastic shrinkage on the strength -to Measurement platform; 2of - Soffit of the formwork; 33 Steel plates; -4Concrete specimen; 1- Measurement platform; 2soffit of the formwork; steel plates; concrete specimen; 5-strength test test in order determine the effect of the curing method and plastic shrinkage on the strength inSCC order to determine the5 effect ofmaking the 6curing method andwere plastic shrinkage on the oncrete of mixing batches was also collected for specimens that used for compression Strain gauges; Nylon membrane evelopment of strain gauges; 6nylon membrane development of SCC development of SCC st inThe order to determine the effect of3 the curing method deformation and plastic shrinkage on the strength to a Figure Measurement of plastic of SCC concrete were mixed according to the process stated in Section 2.3, then discharged Figure Measurement of plastic deformation of SCC The concrete were mixed according to the process stated in Section 2.3, then discharged to to a evelopment of SCC The concrete mixed according to the process stated Section 2.3, then discharged ucket, and poured into the were measurement form Every one hour, theindata of plastic shrinkage were a Table Concrete mixing process ofone the experiment bucket, and and poured intointo the the measurement form Every one hour, the of shrinkage were were bucket, poured form Every hour, thedata data of plastic plastic shrinkage ecorded until the were 22nd hour after themeasurement concrete placement The experiment results were recorded in The concrete mixed to the process stated in Section 2.3, then discharged to a ndthendaccording Experiment with water/power ratio of 0.35 in humid condition; Experiment with the warecorded untiluntil the the 22 22hour after thethe concrete placement The experiment results were recordedinin recorded hour after concrete placement The experiment results were recorded he table form, and were analyzed and presented in graph diagrams Step into Content Time ter/power ratio ofwere 0.3 in humid condition; Experiment with the data water/power ratioshrinkage of 0.35 inwere dry ucket,the and poured measurement form Every one hour, the of plastic table form, andthe analyzed and presented inin graph diagrams the table form, and were analyzed and presented graph diagrams nd condition Three curing methods were carried out for each to examine effect of curingin Experiment ecorded until the hour after50% the(water concrete placement Theexperiment experiment results the were recorded 1:22 Adding + additives) +the 100% stone no minute 3.1 Experiment 1: method on plastic deformation process of SCC at early hardening stages, including: curing 3.1 Experiment 1:was conducted he table form, and were analyzed and presented inthgraph diagrams The 1st experiment on 20 January 2018 The weather was humid, -The KBD (free evaporation of water under the influence of the natural environment); watering - drizzling, TNdrizzling, th Adding gradually (cementon + powder), and mixing the weather was humid, th 1st experiment was conducted 20 January 2018 The 1.5 minutes The 1st experiment was conducted on 20 January 2018 The weather was humid, og and cool with gentle windy The concrete after mixing with the water/power ratio of 0.35 was (watering the specimens every one hour), nylon membrane - BNL (dry curing method, covering thedrizzling, materials evenly Experiment 1: with and cool gentle windy The concrete after mixing with the water/power ratio of 0.35 0.35 was fog and cool with gentle windy The concrete after mixing with the water/power ratio of was ouredfog into the measurement form at 10:15am and since 1:15pm the concrete began to shrink specimen surfaces by nylon to minimize the water evaporation) At the same time, the plastic concrete The th remaining materials (sand +2018 water+ additives), poured into themeasured measurement form at 10:15am and since 1:15pm the concrete began to shrink shrink The 1st experiment was on 2010:15am January weather was humid, drizzling, lasticThe deformation from the gauges was converted to the unit type of millimeter per one poured theAdding measurement form at and sinceThe 1:15pm theand concrete began to The of mixing wasconducted also collected for making specimens that were used for compression test in intobatches minutes mixing all materials evenly plastic deformation measured from theshown gauges was totothe type per one one meter incool concrete length The results were in Fig.4 og and with gentle windy Theof concrete after mixing with the water/power ratioof ofmillimeter 0.35 wasper plastic from the gauges wasconverted converted the unitstrength type ofdevelopment millimeter order todeformation determine themeasured effect the curing method and plastic shrinkage onunit the inSCC length The were shown of 4concrete Stopping and waiting minutes in concrete length The results were shown inFig.4 Fig.4.the concrete began to 5shrink ouredmeter intometer the measurement form atresults 10:15am and sincein1:15pm The lastic deformation measured the gauges was converted to the unit type of millimeter per one Mixingfrom again minutes 43 meter in concrete The results the were shown in Fig.4 length.Discharging mixture Cuong, N H et al / Journal of Science and Technology in Civil Engineering The concrete were mixed according to the process stated in Section 2.3, then discharged to a bucket, and poured into the measurement form Every one hour, the data of plastic shrinkage were recorded until the 22nd hour after the concrete placement The experiment results were recorded in the table form, and were analyzed and presented in graph diagrams 3.1 Experiment The 1st experiment was conducted on 20th January 2018 The weather was humid, drizzling, fog and cool with gentle windy The concrete after mixing with the water/power ratio of 0.35 was poured into the measurement form at 10:15 AM and since 1:15 PM the concrete began to shrink The plastic deformation measured from the gauges was converted to the unit type of millimeter per one meter in concrete length The results were shown in Fig Shrinkage Deformation (mm/m) 0.00 -0.20 Time (h) 10 12 14 16 18 Humidity 100 Temp 29.0 20 28.0 90 27.0 80 70 26.0 -0.40 60 25.0 50 -0.60 24.0 -0.80 40 23.0 30 22.0 -1.00 20 Temperature 21.0 -1.20 No-Curing wrapping by nylon memberance Humidity 10 20.0 Watering (a) Shrinkage deformation 10 11 12 13 14 15 16 17 18 (h) (b) Weather conditions Figure Plastic deformation of SCC specimens for different curing method – Experiment The results show that with the three curing methods, plastic deformation of SCC took place mainly in the first hours to hours after the concrete was mixed This deformation process then continued but at a slower rate; and it seems to be negligible Therefore, the plastic deformation process might be considered to finish within the first hours to hours (Fig 4) Plastic shrinkage occurred in the specimens in the cases of using nylon membrane and watering were not much different This could be explained that the humid and cool conditions produce a humid temperature environment which slows the rate of water evaporation down and limits plastic deformation Samples cured with nylon membrane method were the smallest in plastic deformation, while those cured with watering method appear as the second smallest in plastic deformation The largest deformation occurred in the no-curing specimens At 5:15 PM, four hours passed from the beginning of plastic shrinkage, the deformation in the case of nylon membrane was 0.29 mm/m, while that in the case of watering and no-curing were 0.38 mm/m and 0.88 mm/m, respectively (Fig 4) These values indicated that the nylon membrane method provided the best humid temperature conditions for the water evaporation at the early stages, better than natural humid conditions As a result, with the climatic conditions and mix design of the 1st experiment, the curing method of nylon membrane is the most effective in reducing plastic deformation at the early hardening stages of SCC 3.2 Experiment The 2nd experiment was conducted on 21st January 2018 The weather was humid, drizzling, fog and cool with gentle windy The concrete after mixing with the water/power ratio of 0.3 was poured 44 Cuong, N H et al / Journal of Science and Technology in Civil Engineering into the measurement form at 10:30 AM Two hours later, at 12:30 PM, the concrete began to shrink The results were shown in Fig The results show that with the three curing methods, plastic deformation of SCC took place mainly in the first hours to hours after the concrete was mixed Therefore, with the water/powder ratio of 0.3, the plastic deformation process might be considered to be finished within the first hours to hours (Fig 5), later than that with the water/powder ratio of 0.35 Similar to the previous experiment, samples cured with nylon membrane method were the smallest in plastic deformation, while those cured with watering method appear as the second smallest The largest plastic deformation occurred in the non-curing specimens At 5:30 PM, five hours after the concrete started to contract, the plastic deformation of the specimens cured by nylon membrane was 0.23 mm/m while that cured by watering was 0.66 mm/m The largest deformation of 1.11 mm/m was happened at the no-curing specimens (Fig 5) Therefore, with the climatic conditions and mix design of the 2nd experiment, the curing method of nylon membrane is still the most effective in reducing plastic deformation at the early hardening stages of SCC There was an obvious trend that the higher the water/powder ratio of SCC is, the longer the plastic deformation process takes Shrinkage Deformation (mm/m) 0 10 12 14 16 18 20 Time (h) Humidity Temp 22 -0.2 -0.4 -0.6 -0.8 -1 -1.2 31.0 90 30.0 80 29.0 70 28.0 60 27.0 50 26.0 40 25.0 30 24.0 -1.4 23.0 -1.6 22.0 No-Curing Watering wrapping by nylon memberance 20 Temperature 10 (a) Shrinkage deformation 11 12 13 14 Humidity 15 16 10 17 18 (h) (b) Weather conditions Figure Plastic deformation of SCC specimens for different curing method – Experiment Shrinkage Deformation (mm/m) 10 12 14 16 18 Time (h) 20 22 -0.5 -1 -1.5 -2 -2.5 -3 No-Curing wrapping by nylon memberance Humidity 90 Temp 35.0 33.0 31.0 29.0 27.0 25.0 23.0 21.0 19.0 17.0 15.0 Watering 80 70 60 50 40 30 20 Temperature Humidity 10 10 11 12 13 14 15 16 17 18 (h) (a) Shrinkage deformation (b) Weather conditions Figure Plastic deformation of SCC specimens for different curing methods – Experiment 45 non-curing specimens At 5:30pm, six hours after the concrete started to contract, the plastic deformation of theAtspecimens cured by after nylonthe membrane 1.45mm/m while of the non-curing specimens 5:30pm, six hours concrete was started to contract, the that plastic deformation the by specimens by nylon The membrane was 1.45mm/m while that the specimensofcured watering cured was 2.00mm/m largest deformation of 2.45mm/m wasof accounted Cuong, N H et al / Journal of Science and Technology in Civil Engineering specimens by watering was (Fig.6) 2.00mm/m The largest of humid 2.45mm/m was accounted for thecured no-curing specimens Therefore, underdeformation thermal and conditions and the mix rd for the no-curing (Fig.6) underofthermal and humid isconditions and the mix in design of the specimens experiment, theTherefore, curing method nylon membrane still the most effective 3.3 Experiment rd design of the plastic experiment, method nylonthe membrane is still the most effective in th of after reducing deformation atcuring the early hardening SCC non-curing Atthe 5:30pm, six hours concrete the plastic The 3rdspecimens experiment was conducted on 04 Februarystages 2018 of The weatherstarted was dryto andcontract, light sunshine non-curing specimens At 5:30pm, six hours after the concrete started to contract, the plastic reducing plastic deformation at the early hardening stages of SCC deformation of theThe specimens cured by with nylon membrane was of 1.45mm/m whileinto that the withThe gentle windy concrete after mixing the water/power ratio 0.35 was poured the of and of watering three experiments showed that despite differences in climatic conditions deformation ofresults the specimens cured by nylon membrane was 1.45mm/m while that of the specimens cured by was 2.00mm/m The largest deformation of 2.45mm/m was accounted measurement form at 10:30 AM At showed 11:30 AM, thedespite concretedifferences began to shrink The results are shownand The results of three experiments that climatic conditions specimens cured watering was (Fig.6) 2.00mm/m The largest deformation ofin 2.45mm/m was accounted concrete mixby designs, curing by nylonTherefore, membrane is the most effective method to minimize plastic forinthe no-curing specimens under thermal and humid conditions and the mix Fig concrete mix designs, curing by nylon membrane is the most effective method to minimize plastic for the no-curing specimens (Fig.6) Therefore, under thermal and humid conditions and the mix rd deformation in the early hardening stages Due to the ability to limit plastic deformation, curing by design of the experiment, the curing method of nylon membrane is still the most effective in With rd all three curing cases, the plastic deformations of SCC took place mainly in the first hours design of thein 3theexperiment, theatcuring method of nylon membrane is stilldeformation, the most effective in deformation early hardening stages Due to the ability to limit plastic curing by st nd reducing plastic deformation the early hardening stages of SCC using membrane also controls surface when to curing by 1watering to plastic 7nylon hoursdeformation after the concrete was mixed, longercracking than thatof inSCC thecompared humid conditions of the and or nonreducing at the early hardening stages using nylon membrane also controls surface cracking when compared to curing by watering or nonexperiments Therefore, under dry conditions, theother plastic deformation was the considered to becured finished curing (Fig.7) In of addition, different from two methods, specimens by nylon The results three experiments showed that curing despite differences in climatic conditions and The results of three experiments showed that curing despite differences climatic conditions and curing (Fig.7) In addition, different from two other methods, the in specimens cured by nylon within hours to hours after concrete placement The plastic deformation process still continued concrete mix designs, curing by nylon membrane is the most effective method to minimize plastic membrane did not curing show any white efflorescence on surface Therefore, it might consider that curing concrete mix designs, by nylon membrane theplastic most effective to minimize plastic membrane did not show any white efflorescence onisto surface Therefore, itmethod might consider that curing after that but at a slower rate (Fig 6) The smallest deformation happened in the case of deformation in the early hardening stages Due the ability to limit plastic deformation, curing by nyloninmembrane also helps in controlling efflorescence on concrete surface curing by by deformation early hardening stages Due towhite the ability to limit plastic deformation, by nylon membrane also helps controlling white efflorescence on concrete curing bythe nylon membrane the second was watering The largest plastic deformation occurredor nonusing nylon membrane alsoinwhile controls surface cracking when compared to surface curing by watering using nylon membrane also controls surface cracking when compared to curing by watering or nonin the non-curing specimens At 5:30 hours after the concrete tospecimens contract, the plastic curing (Fig.7) Inbeing addition, different from two other curing methods, cured byplastic nylon Although smaller thanPM, thesix plastic deformation instarted thethecase of no-curing, curingAlthough (Fig.7) Inbeing addition, different other curing methods, specimens cured byplastic nylon smaller thanfrom the two plastic deformation in thethecase of no-curing, membrane didof not any white on surface itthat might deformation theshow specimens cured efflorescence byby nylon membrane was 1.45Therefore, mm/mthan while that when of consider the specimens deformation curing watering was much larger curingthat by curing nylon membrane did nothappened showwhen anywhen white efflorescence on surface Therefore, itthat might consider curing deformation happened curing watering was much larger than when curingthat by nylon by cured nylonby membrane also2.00 helps inby controlling white efflorescence on concrete surface watering was mm/m The largest deformation of 2.45 mm/m was accounted for the membrane According to in [2,12], in hot weather conditions solar radiation, watering by nylon membrane also helps controlling white efflorescence onwith concrete surface membrane According to (Fig [2,12], in hot weather conditions with highhigh solar watering no-curing specimens 6) Therefore, under thermal and humid conditions andradiation, the mix design of plastic Although being smaller than the plastic deformation in the case of no-curing, method not effective even it result canthe result in reduction ofconcrete the the concrete quality Many research results rdis effective Although being smaller than deformation the case of no-curing, plastic method is 3not even it can inplastic reduction of the quality Many research results the experiment, the curing membrane still in most effective reducing plastic deformation happened when method curing of bynylon watering was is much larger than thatinwhen curing by nylon deformation happened when curing bystages watering was much largerof than curing by nylon that under the effect of periodic watering, the temperature ofthat water is much lower than deformation at the early hardening of SCC showshow that under the effect of periodic watering, the temperature water iswhen much lower than the the membrane According to [2,12], in hot weather conditions with high solar radiation, watering membrane According to [2,12], in hot weather conditions with high solar radiation, watering temperature ofeffective the heated surface, which leads to a continuous heat pulse with the research deviation The of three experiments showed that differences in climatic conditions and contemperature ofresults the heated surface, which leads to adespite continuous pulse with the deviation up results toup to method not it result can result in reduction of the heat concrete quality Many method is notiseffective eveneven it can in reduction of the concrete quality Many research results cretethat mixThis designs, byadversely nylon membrane is the most effective method to minimize plastic defor- of the 30÷50C problem might adversely affect the structure physical-mechanical properties of show under thecuring effect of periodic watering, the temperature of water is much lower 30÷50C problem might affect the structure and and physical-mechanical properties show that This under the effect of periodic watering, the temperature of water is much lower thanthan the mation in the early hardening stages Due to the ability to limit plastic deformation, curing by using of heated the heated surface, which a continuous the deviation up to SCC of the SCC.temperature temperature surface, which leadsleads to a to continuous heat heat pulsepulse withwith the deviation up to nylon membrane also controls surface cracking when to curing by watering or non-curing 30÷50C problem might adversely affect thecompared structure physical-mechanical properties 30÷50C This This problem might adversely affect the structure and and physical-mechanical properties of of Generally, curing by nylon membrane is the most effective method to ensure the quality of (Fig 7) In addition, different from two other curing methods, the specimens cured by the nylon memGenerally, curing by nylon membrane is the most effective method to ensure quality of SCC SCC brane did not show any white efflorescence on surface Therefore, it might consider that curing by surface SCCSCC surface Generally, curing by nylon membrane is most the most effective method to ensure the quality Generally, curing byhelps nylon is the effective method to ensure the quality of of nylon membrane also in membrane controlling white efflorescence on concrete surface surface SCC surface a) SCC b) a) b) a) a) c) c) c) c) (a) No-curing b) b) d) d) d) d) (b) Wrapping by nylon membrane (c)Figure WhiteFigure efflorescence-cured bycracking watering (d)curing Watering 7: Surface cracking and white efflorescence in the cases 7: Surface and white efflorescence in the curing cases Figure 7:b)Surface cracking and white efflorescence inefflorescence-cured theefflorescence-cured curing cases by watering; a) No curing; Wrapping by nylon membrane; c) White a)–No – curing; by nylon membrane; c) White Figure 7.Wrapping Surfacecracking cracking and efflorescence in the curing Figure 7:b)Surface and white efflorescence in the cases curing cases by watering; d)white Watering d) Watering a) No – curing; b) Wrapping by nylon membrane; c) White efflorescence-cured by watering; The effect conditions andplastic curing plastic deformation of SCC a)ofNoclimatic – being curing; b)conditions Wrapping by nylon membrane; c)on White efflorescence-cured by SCC watering; The effect of climatic and curing methods the plastic deformation of Although smaller than the deformation inon thethe case of no-curing, plastic deformation d)methods Watering d)and Watering To assess the effect of by climatic conditions curing methods the deformation of of happened when curing watering was muchand larger than that methods whenon curing by nylon membrane To of assess the effect of climatic conditions curing on plastic the plastic deformation The effect climatic conditions and curing methods on the plastic deformation of SCC SCC,SCC, the results of plastic deformation of experiments conducted in the humid condition and results of plastic deformation of experiments conducted in hot, the deformation hot, humid condition Thethe effect ofthe climatic conditions and curing methods on the plastic of SCC and dry condition with same water/powder ratio of 0.35 are compared.Equipment, mixing process, To assess the effect of climatic conditions and curing methods on the plastic deformation of 46 of 0.35 are compared.Equipment, mixing process, dry condition with the same water/powder ratio To assess the effect of climatic conditions and curing methods on the plastic deformation SCC, the results of plastic deformation of experiments conducted in the hot, humid condition and of SCC, the with resultstheofsame plastic deformationratio of experiments in the hot, humid dry condition water/powder of 0.35 are conducted compared.Equipment, mixingcondition process, and dry condition with the same water/powder ratio of 0.35 are compared.Equipment, mixing process, Cuong, N H et al / Journal of Science and Technology in Civil Engineering According to [2, 12], in hot weather conditions with high solar radiation, watering method is not effective even it can result in reduction of the concrete quality Many research results show that under the effect of periodic watering, the temperature of water is much lower than the temperature of the heated surface, which leads to a continuous heat pulse with the deviation up to 30◦C to 50◦C This problem might adversely affect the structure and physical-mechanical properties of SCC Generally, curing by nylon membrane is the most effective method to ensure the quality of SCC surface The effect of climatic conditions and curing methods on the plastic deformation of SCC To assess the effect of climatic conditions and curing methods on the plastic deformation of SCC, the results of plastic deformation of experiments conducted in the hot, humid condition and dry condition with the same water/powder ratio of 0.35 are compared Equipment, mixing process, manpower and materials were the same Concrete was mixed, poured into the mold at 10:30 AM The measurement was carried out during twenty-two hours since the concrete began to contract Experimental results as shown in Fig indicate that under dry condition, the plastic shrinkage took place after one hour, while under humid condition, it occurred after three hours It demonstrates that plastic shrinkage occurred much sooner under dry condition than under humid condition The reason is that humid condition allows the rate of water evaporation to be slower, so that concrete has a good temperature-humidity environment to continue hydrating Therefore, the process of plastic shrinkage happens later The value of plastic deformation of SCC under dry condition is much larger than that under humid condition At the 22nd hour (Fig 8) with the same method of curing by nylon membrane, the plastic deformation was 1.53 mm/m under dry condition while only 0.42 mm/m under humid condition This might be explained that under dry condition, the dehydration takes place with high speed and volume, which causes plastic deformation to start early with high value Plastic Shrinkage (mm/m) 0.00 Time (h) 10 11 12 13 14 15 16 17 18 19 20 21 22 23 -0.50 -1.00 -1.50 -2.00 -2.50 -3.00 Humid-0.35-KBD Dry-0.35-KBD Humid-0.35-BNL Dry-0.35-BNL Humid-0.35-TN Dry-0.35-TN Figure Plastic deformation of SCC with different climatic conditions and curing methods The effect of mix design and curing methods on the plastic deformation and compressive strength of SCC The results as shown in Fig indicate that in the case of watering (TN) or no curing (KBD), the plastic deformation of the specimen created with 0.3 water/powder ratio was greater than that of the 47 Cuong, N H et al / Journal of Science and Technology in Civil Engineering specimen created with 0.35 water/powder ratio Conversely, as curing by nylon membrane, the plastic deformation occurred with the case of 0.35 water/powder ratio was larger However, the difference was not significantly higher As a general trend, SCC with the higher ratio of water/power tends to produce smaller plastic deformation This trend might be caused by the greater water/powder ratio the smaller amount of powder (cement and fly ash), that means the amount of aggregate in the mixture is bigger Therefore, the amount of binding paste remains smaller, which leads to smaller plastic deformation Obviously, in the mixture of aggregates and cement paste, plastic deformation only occurs where the cement paste is distributed Plastic Shrinkage (mm/m) 0.00 Time (h) 10 11 12 13 14 15 16 17 18 19 20 21 22 -0.20 -0.40 -0.60 -0.80 -1.00 -1.20 -1.40 -1.60 Humid-0.35-KBD Humid-0.35-BNL Humid-0.35-TN Humid-0.3-KBD Humid-0.3-BNL Humid-0.3-TN Figure Plastic deformation of SCC with different mix designs From the strength development curves of SCC with the both cases of water/powder (N/B) ratio of 0.35 and 0.3, it can be seen that the samples cured by nylon membrane have the highest compressive strength (the dashed line in Fig 10) At the 28th day of age, for the ratio of 0.35, the strength of SCC in the cases of nylon membrane, watering and no-curing were 536.0 daN/cm2 , 480.0 daN/cm2 and 474.0 daN/cm2 , respectively Those values reach about 100.75%, 90.22% and 89.10% respectively of strength of the samples that were cured under the standard condition For the water/powder ratio of 0.3, strength of the samples cured by the above three curing methods were 630.0 daN/cm2 , 584.0 daN/cm2 and 537.0 daN/cm2 respectively, which reach 101.2%, 93.82%, 86.27% respectively of the strength of SCC cured under the standard condition Under the same test conditions, a correlation can be observed that the greater the plastic deformation, the lower the compressive strength As shown in Fig 9, under humid condition and the water/powder ratio of 0.35, the smallest plastic deformation was recorded in SCC specimens that are cured by nylon membrane (solid line with dots) They also provided the best value of compressive strengths (the dashed line as seen in Fig 10) This correlation is also true for samples which are cured by other methods and under dry condition Generally, the method of curing by nylon membrane not only ensures the quality of concrete surface by minimizing surface cracking and white efflorescence, but also provides the best compressive strength which exceeds the standard curing method (see Fig 10) This demonstrates that the process of hardening and developing strength of SCC takes place in the best condition when SCC members are cured by nylon membrane 48 Cuong, N H et al / Journal of Science and Technology in Civil Engineering (daN/cm2) 600.0 (daN/cm2) 700.0 N/B=0.35- Humid conditions N/B=0.3- Humid conditions 600.0 500.0 500.0 400.0 400.0 300.0 300.0 200.0 Humid-0.35-KBD Humid-0.35-BNL 100.0 200.0 Humid-0.35-TN Humid-0.35-TC Humid-0.3-KBD Humid-0.3-BNL 100.0 0.0 Humid-0.3-TN Humid-0.3-TC 0.0 10 15 20 25 (day) 30 (a) The water/powder ratio of 0.35 10 15 20 25 (day) 30 (b) The water/powder ratio of 0.30 Figure 10 Strength development of SCC with different curing methods under humid conditions Conclusions From the experimental results, the paper draws the conclusions as follows: Under two climatic conditions, humid and dry, curing by nylon membrane is the most effective method in minimizing plastic deformation of SCC in the early hardening stage With the reduction of plastic shrinkage, nylon membrane also controls surface cracking and white efflorescence better than watering and no-curing methods Accordingly, in order to obtain the best quality of concrete surface, nylon membrane should be chosen It is also suitable for use in construction sites Under dry conditions, the plastic deformation of SCC specimens occurs earlier greater than humid conditions The period of plastic deformation occurring is from four to five hours under humid conditions and from six to seven hours under dry conditions Under the same climatic conditions, the higher the water/powder ratio, the smaller the plastic shrinkage tend to be The curing method of nylon membrane provides the highest results of compression strength, which is greater than the compression strength of SCC cured under the standard condition This shows that nylon membrane can control the water evaporation of SCC and minimize plastic shrinkage along with the creation of an ideal temperature-humidity environment for forming the structure and developing the strength of SCC Besides, a correlation can be observed that the larger the plastic deformation of SCC, the lower the compressive strength References [1] Huong, N T T (2013) Causes of crack and measures to limit the crack for concrete and reinforced concrete of works used seaside protection Journal of Water Resource & Environmental Engineering, (42):69–74 [2] ACI committee (2008) ACI 224R-01, Control of Cracking in Concrete Structures [3] Dich, N T 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concrete Viet Nam Journal of Construction, 1:89–91 [9] ACI committee (2008) ACI 308R-01, Guide to Curing concrete [10] Boel, V (2006) Microstructure of self-compacting concrete in relation with gas permeability and durability aspects Doctoral Thesis, Magnel Laboratory for Concrete Research, Ghent University, Belgium ă Aggoun, [11] Craeye, B., De Schutter, G., Desmet, B., Vantomme, J., Heirman, G., Vandewalle, L., Cizer, O., S., Kadri, E H (2010) Effect of mineral filler type on autogenous shrinkage of self-compacting concrete Cement and Concrete Research, 40(6):908–913 [12] Loser, R., Leemann, A (2009) Shrinkage and restrained shrinkage cracking of self-compacting concrete compared to conventionally vibrated concrete Materials and Structures, 42(1):71–82 [13] Oliveira, M J., Ribeiro, A B., Branco, F G (2015) Curing effect in the shrinkage of a lower strength self-compacting concrete Construction and Building Materials, 93:1206–1215 [14] Tongaroonsri, S., Tangtermsirikul, S (2009) Effect of mineral admixtures and curing periods on shrinkage and cracking age under restrained condition Construction and Building Materials, 23(2):1050–1056 [15] Khoa, H N., Hai, T H (2013) Slump loss of mixed concrete under climatic conditions during storage process prior to pouring into formwork systems Journal of Science and Technology in Civil Engineering (STCE)-NUCE, 7(3):29–39 50 ... along e) Spreading plastic h) steel Installing gauges concrete into the measuring plastic concrete into the f) Curing g) Removing the the form andand measuring plastic concrete into the f) Curing. .. than the deformation inon thethe case of no -curing, plastic deformation d )methods Watering d)and Watering To assess the effect of by climatic conditions curing methods the deformation of of happened... conditions and curing methods on the plastic deformation of SCC SCC,SCC, the results of plastic deformation of experiments conducted in the humid condition and results of plastic deformation of