Effect Of Different Curing Methods Research Articles

The Effect of Different Curing Methods on the Properties of Reactive Powder Concrete Reinforced with Various Fibers

The Effect of Different Curing Methods on the Properties of Reactive Powder Concrete Reinforced with Various Fibers

DEVELOPMENT OF COMPRESSIVE STRENGTH PREDICTIVE MODELS OF SELF-COMPACTING CONCRETE CURED USING DIFFERENT CURING METHODS

Curing is the process of controlling the rate and extent of moisture loss, relative humidity and temperature from newly poured concrete for a certain period of time after it has been cast or finished to ensure that the cement has been properly hydrated and the concrete has hardened. The concrete strength, durability and other physical properties are affected by curing and application of the various types as it relates to the prevailing weather conditions in a particular locality, as curing is one of many requirements for concrete production, as such it is important to study the effect of different curing method. The concrete cube specimens produced with cement, fine aggregate, and coarse aggregate mix-ratio of 1:2.23:1.62 were prepared with a water-cement ratio of 0.5 and superplasticizer (SP) dosages of 0.5%, 1.0%, and 1.5%. The SP dosages were computed as percentages by weight of the cement content. The cubes were tested for compressive strength after curing for 7, 14, 21, 28, and 56 days using three curing methods namely; Immersion, open air, and wet burlap curing methods. This study assessed the effect of different curing methods on compressive strength of self-compacting concrete through the development of a mathematical method to model and analyze the effect of the curing methods used on the compressive strength of the SCC and also to validate the reliability of the method used. Data Fit software was used in the model development, the curing age and super-plasticizer dosage were used as independent variables while the compressive strength...

Concrete Curing Performance Assessment Based on Gas Permeability Testing in the Lab and on Site.

Durability is an essential aspect of the lifetime performance of concrete components. The adequate surface quality and thus the service life of concrete can be achieved, among other things, by appropriate curing during hydration. To measure and control the curing quality, appropriate procedures are required. Gas permeability allows conclusions to be drawn about the porosity of concrete, which has a significant impact on durability. In this contribution, the effect of different curing methods on gas permeability is presented with the help of laboratory and on-site tests, showing that inadequate curing leads to increased permeability in the near-surface area of concrete. The measurement results of concrete samples and components with the same composition but varying curing treatment are compared and evaluated. Influences such as concrete composition and environmental factors on the quality of concrete are observed, and recommendations are made for a reliable assessment of the surface quality as a result of the investigated curing measures.

Effect of different curing methods on the preparation of carbonized high-titanium slag based geopolymers

This work reported a rapid preparation route of carbonized high titanium slag (CHTS) based geopolymer with better mechanical properties by employing different curing techniques. The combination pre-curing treatment (first thermal heating at 60℃ for 6 h and then microwave radiation at 210 W for 15 min) was confirmed as an effective preparation method, and the compressive strength of the geopolymer reached 76.33 MPa. Mechanism analysis indicated that the facilitating effect of the combination pre-curing process in different reaction stages has resulted in the better formation of hydration gels in geopolymer samples. Thus, a high-quality hydration structure with the lowest porosity and micro-cracks was obtained.

Effect of Selected Curing Methods on Density and Compressive Strength of Concrete for Technological Self-Reliance

The quest to deliver construction projects within the shortest possible time handled many engineers to maneuver curing ages of concrete and this has been a major concern in construction industries due to associated failures of concrete members emanating from improper curing. This study therefore aimed at investigating the effect of different curing methods on density and compressive strength of concrete with a view to enhancing technological self-reliance of the nation. Concrete cube specimens (150 mm × 150 mm × 150 mm) were cast using mix ratio 1:2:4 with 0.5 water-cement ratio. The concrete specimens were cured for 28 days using open air, ponding, sprinkling and dry covering curing methods. The compressive strength and density were evaluated. The data were validated. The results showed that the compressive strength increases with increasing curing age. The respective compressive strength values obtained for ponding, sprinkling, dry covering and open air curing methods were 22.04, 20.48, 17.28 and 16.02 respectively. The curing methods have compressive strengths in the order Ponding < sprinkling < dry covering < open air. The results of the curing methods on density were also noticed to be directly proportional to strength. Appropriate curing methods of concrete had greater impact in influencing physical and mechanical properties of concrete.Keywords: Concrete, Curing methods, Strength, Sustainable growth

Effect of Curing Methods on the Compressive Strength of Palm Kernel Shell Aggregate Concrete

High cost of building construction in the country has remained a major source of concern to successive government in the nation. Building materials constitute approximately 60-70% of the building cost. In view of this, the need for alternate building materials is imminent. This research work focuses on assessment of effect of different curing methods on the compressive strength of palm kernel shell aggregate concrete. All materials were collected at Ede, Osun state. The stages involved in this research are material collection, batching and mixing, casting of concrete cubes, slump test, curing, and compressive strength test. The tests carried out were x-ray fluorescence, slump test and compressive strength. Four different curing methods were used; water, air, salt water, and detergent to cure concrete with two mixing ratios of 1:2:4 and 1:1½:3. It can be observed that the Palm Kernel Shell (PKS) contains mainly Iron (Fe), Potassium (K), Calcium (Ca), Manganese (Mn) elements and other impurities. From the slump test results, it can be deduced that 1:1½:3 gave a better slump as expected. The compressive strength of cube ranges from 2.244 to 3.852N/mm2 Based on the results, the curing methods has a significant effect on the compressive strength of the PKS aggregate concrete.

Study of Inkjet-Printed Silver Films Based on Nanoparticles and Metal-Organic Decomposition Inks with Different Curing Methods.

Currently, inkjet printing conductive films have attracted more and more attention in the field of electronic device. Here, the inkjet-printed silver thin films based on nanoparticles (NP) ink and metal-organic decomposition (MOD) ink were cured by the UV curing method and heat curing method. We not only compared the electrical resistivity and adhesion strength of two types of silver films, but also studied the effect of different curing methods on silver films. The silver films based on NP ink had good adhesion strength with a lowest electrical resistivity of 3.7 × 10−8 Ω·m. However, the silver film based on MOD ink had terrible adhesion strength with a lowest electrical resistivity of 2 × 10−8 Ω·m. Furthermore, we found a simple way to improve the terrible adhesion strength of silver films based on MOD ink and tried to figure out the mechanisms. This work offers a further understanding of the different performances of two types of silver films with different curing methods.

The Effect of Different Curing Method and Water /Cement Ratios on Concrete Compressive Strength

At this paper, an experimental investigation was conducted to explore the effect of different curing methods and water cement ratios on compressive strength and density of normal weight concrete. The samples had been submitted to five different curing methods including: water curing (standard curing), air curing and three types of colored plastic bags curing including (Transparent, white and black bags). The effect of w/c ratio on compressive strength at different curing had been studied too. Test results shows that the curing by plastic bags gives accepted results compared with standard curing and better than air curing. For all kinds of referenced curing the increasing in w/c ratios decrease the compressive strength, and the density of concrete samples reduces at air and plastic bags curing compared with standard curing..

Effect of Curing Method on Concrete with Palm Oil Fuel Ash as a Cement Replacement

In this paper, the effect of different curing methods on the strength of concrete with palm oil fuel ash as a cement replacement is investigated. An experimental program was carried out to study the effect of five different curing methods, i.e., water curing (WC), air curing (AC), plastic-wrapped curing (PC), oven and water curing (OWC), and oven and air curing (OAC), on the compressive and flexural strengths of palm oil fuel ash concrete (POFA20), where 20% of the cement was replaced by palm oil fuel ash. The results obtained from this investigation showed that POFA20-WC has the highest compressive and flexural strength, whilst POFA20-AC has the lowest at the age of 28 days. Both of the POFA20-OWC and POFA20-OAC have the highest compressive and flexural strength at the age of 3 days. The results emphasize the positive effect of oven curing procedure to achieve high compressive and flexural strength at early stage. However, the rate of hydration started to decrease at later stages, which leads to much lower rate of gaining strength in POFA20-OWC and POFA20-OAC. Water curing method is thus recommended in the construction industry except for extraordinary requirements and/or circumstances.

Effect of Different Curing Methods by Durability Index Tests

Effect of Different Curing Methods by Durability Index Tests

The Effect of Different Curing Methods on the Compressive Strength of Eggshell Concrete

The work assesses the effect of different curing conditions on the compressive strength of the eggshell concrete. Two different qualities of the eggshell powder were used to make concrete with 0.45 water/cement ratio. The eggshell powders were treated as partial cement replacement of 5%, 10%, 15% and 20%. The concrete cube specimens (100 x 100 x 100) mm were exposed to two different environments (full water curing and open-air curing) for 1, 7 and 28 days. The results exhibit that the initial strength growth for the compressive strength with increases with the percentage of the replacement up to 15%, being this behaviour more evident for the full water curing environment up to 67.53%. The 28- days compressive strength of the eggshell concrete for full water curing and open air curing were found at 49.23 MPa and 46.34 MPa respectively. However, the concrete specimens lost 24.7% and 34.83% when the eggshell powder replace up to 20% of the partial cement replacement for full water curing and open air curing. Thus, water curing is found to be more suitable compared to to open air curing.

Regression models for compressive strength of concrete under different curing conditions

Effect of different curing methods on the compressive strength of concrete was investigated. A total of 69 concrete cubes of size 150 mm was cast and cured under five different conditions (immersion in water, sprinkling with water, moist sand covering, polythene covering and air curing) for 3, 7, 14 and 28 days. At the expiration of curing ages, compressive strength was determined and regression analysis was conducted. The concrete cured with these techniques was equally subjected to water penetration test. The results showed that Polythene covering method produced concrete specimen with the highest compressive strength of 23.41 Nmm −2 followed by Immersion in water (22.86 Nmm −2 ). Regression models formulated for each condition indicated that the strength development was dependent on methods of curing. From the results, it was concluded that the compressive strength of concrete depends on the medium in which they were cured and there exist a positive correlation between the compressive strength of concrete and curing age.

Effect of different curing methods on bio-chemical parameters and marketable bulbs of onion cv. Bellary red during storage

The present investigation was carried out to study the effect of different curing methods on biochemical parameters and percent marketable bulbs of onion during storage. The methods used for curing of onion bulbs are curing under forced hot air dryer, polytunnel, 35 per cent shade and 100 per cent shade with foliage and without foliage respectively. Among different curing methods, onion bulbs cured under 35 per cent shade with foliage showed maximum total soluble solids (14.22%), ascorbic acid retension (7.45 mg/100 g), reducing sugars (2.74%), non reducing sugars (5.18%) and total sugar (7.92%) and which was followed by the bulbs cured under 35 per cent shade without foliage. The highest percent of marketable bulbs was observed in onion bulbs cured under 35 per cent shade with foliage (61.48%) followed by the bulbs cured under 35 per cent shade without foliage (59.28%) and the lowest was observed in onion bulbs cured under forced hot dryer without foliage (43.62%) after two months of storage.

Effect of Different Curing Methods on Tensile bond Strength Soft Acrylic Liner to Heat-Cured Acrylic Resin

Effect of Different Curing Methods on Tensile bond Strength Soft Acrylic Liner to Heat-Cured Acrylic Resin

Impact of curing condition on pH and alkalinity/acidity of structural wood adhesives

AbstractNine formulations were selected for evaluating the effect of different curing methods on pH and alkalinity or acidity of various structural wood adhesives. These included four phenol–formaldehyde (PF) resins with high pH, one phenol–resorcinol–formaldehyde (PRF) resin with intermediate pH, two melamine–urea–formaldehyde (MUF) resins, and two melamine–formaldehyde (MF) resins with low pH. The four curing methods used in the study were: (1) curing at 102–105°C for 1 h (based on CSA O112.6‐1977), (2) four‐hour curing at 66°C followed by 1‐hour curing at 150°C (based on ASTM D1583‐01), (3) curing at room temperature overnight (based on ASTM D 1583‐01), and (4) cured adhesive squeezed out from glue lines of bonded shear block samples. The effect of the different methods on pH and alkalinity/acidity of the cured adhesive depended strongly on the individual adhesives. For the PF, the alkalinity was different for the different formulations in the liquid form, while in the cured form, the difference in the alkalinity depended on the curing method used. The MF and the MUF were the adhesives most affected by the method used. In particular, the MUF showed much higher cured film pH values when cured by method 2 compared to the other three methods, while both the cured MF and MUF exhibited quite variable acidity values when cured with the different methods. The PRF showed reasonably uniform cured film pH but varying acidity values when cured with the different methods. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Influence of the curing method on the post-polymerization shrinkage stress of a composite resin

The aim of this study was to evaluate the effect of different curing methods on the stress generated by the polymerization shrinkage of a restorative composite in two moments: immediately after light exposure and after 5 min. Photoactivation was performed using two different light sources: (1) xenon plasma arc (PAC) light (1,500 mW/cm2 – 3s) and (2) a quartz-tungsten-halogen (QTH) light with three light-curing regimens: continuous exposure (40 s at 800 mW/cm2 – CL); soft-start (10 s at 150 mW/cm2 and 30 s at 800 mW/cm2 - SS) and intermittent light [cycles of 4 s (2 s with light on at 600 mW/cm2 and 2 s of light off), for 80s – IL]. The composite resin was applied between two 5-mm diameter metallic rods, mounted in a servohydraulic machine. The maximum stress was recorded immediately after light exposure (FF) and after 5 min (5F). The results were submitted to ANOVA and Tukey's test (5%). For each method, the results obtained in FF and 5F were, respectively: CL (3.58 and 4.46 MPa); SS (2.99 and 4.36 MPa); IL (3.11 and 4.32 MPa) and PAC (0.72 and 3.27 MPa). The stress generated by the polymerization shrinkage during light exposure can be associated with the photoactivation method used. A significant increase in the stress level was observed during the post-curing period up to 5 min, for all evaluated methods.