scholarly journals Method for determining the degree of influence of the heating temperature on the strength set of concrete based on isotherms

2021 ◽  
Vol 79 (1) ◽  
pp. 283-288
Author(s):  
E.B. Utepov ◽  
◽  
A.S. Tulebekova ◽  
D.A. Akhmetov ◽  
E.N. Root ◽  
...  
Keyword(s):  
Heating Temperature ◽  
Concrete Strength ◽  
Curing Temperature ◽  
Strength Development ◽  
Numerical Comparison ◽  
Test Results ◽  
Strength Gain ◽  
Sample Heating ◽  
Temperature Regimes ◽  
Alternative Approach

The article presents the development of an alternative approach to determining the degree of influence of the curing temperature on the concrete strength gain, based on the construction of isotherms. Based on the test results, isotherms were plotted, representing the graphs of strength gain for each of the temperature regimes. Visual and numerical comparison of the concrete strength values obtained from isotherms gave an understanding of the degree of influence of sample heating on strength development.

scholarly journals Compressive Strength Gain Behavior and Prediction of Cement-Stabilized Macadam at Low Temperature Curing

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Yongli Xu ◽  
Guang Yang ◽  
Hongyuan Zhao
Keyword(s):  
Compressive Strength ◽  
Low Temperature ◽  
Curing Temperature ◽  
Strength Development ◽  
Construction Process ◽  
Strength Gain ◽  
Estimation Model ◽  
Maturity Method ◽  
Temperature Ranges ◽  
Natural Temperature

For cement-based materials, the curing temperature determines the strength gain rate and the value of compressive strength. In this paper, the 5% cement-stabilized macadam mixture is used. Three indoor controlled temperature curing and one outdoor natural curing scenarios are designed and implemented to study the strength development scenario law of compressive strength, and they are standard temperature curing (20°C), constant low temperature curing (10°C), day interaction temperature curing (varying from 6°C to 16°C), and one outdoor natural temperature curing (in which the air temperature ranges from 4°C to 20°C). Finally, based on the maturity method, the maturity-strength estimation model is obtained by using and analyzing the data collected from the indoor tests. The model is proved with high accuracy based on the validated results obtained from the data of outdoor tests. This research provides technical support for the construction of cement-stabilized macadam in regions with low temperature, which is beneficial in the construction process and quality control.

Evaluation of Contributing Factors on Strength Development of Lime Stabilized Artificial Organic Soils Using Statistical Design of Experiment Approach

2014 ◽  
Vol 905 ◽  
pp. 362-368 ◽  
Author(s):  
Felix N.L. Ling ◽  
Khairul Anuar Kassim ◽  
Ahmad Tarmizi Abdul Karim ◽  
S.C. Ho
Keyword(s):  
Organic Matter ◽  
Statistical Design ◽  
Organic Soil ◽  
Curing Temperature ◽  
Organic Soils ◽  
Strength Development ◽  
Test Results ◽  
Contributing Factors ◽  
Strength Enhancement ◽  
Factor Interactions

Lime is widely used as chemical stabilizer in soft soil stabilization. However, lime is reported to be less effective when dealing with organic soil. It is believed that the organic matter in the soil will retard the pozzolanic reaction which is responsible for strength enhancement. The heterogeneity nature of the organic matter in the soil makes the study complicated and reduced the repeatability of the test results. Hence, artificial organic soil with known organic matter and content are preferred by researchers when repeatability of the test results are required in determining the influential effect of each contribution factor. Various factors such as additive contents, effect of aging (curing periods), curing temperature, density of materials and moisture content are reported by previous researchers as the potential contributing factors towards the strength development. It is believed that the interaction of the factors also will contribute to the strength enhancement. Hence, this study is carried out to evaluate the contributing factors and its interactions on strength development of artificial organic soils with known type and contents of organic matter. Statistical design of experiment (DOE) approach was utilized to evaluate the factors and its interaction on the strength development of lime stabilized artificial organic soils by using commercial statistics package. Three main factors were investigated: effect of organic content, effect of curing periods, and effect of additive, while other factors namely curing temperature, molding water content, types of compaction and compactive effort were keep constant through controlled experiments. Processed kaolin (inorganic material) is mixed with humic acid (organic matter) to simulate the organic soil which comprised of inorganic soil and organic matter. The density of the soil specimen and its moisture content were recorded before and after the curing process. General Linear Model (GLM) was utilized to determine the significance of the main factors, two-factor interactions, and three factor interactions. The significance factors and interactions were utilized in multiple regression analysis to develop the strength prediction model which can be utilized to predict the strength of stabilized materials within the inference space defined by the experiment.

Experimental Research of the Rapid Set Cement Concrete for Rapid Repair of Concrete Pavements

2013 ◽  
Vol 634-638 ◽  
pp. 2697-2701 ◽  
Author(s):  
Ren Juan Sun ◽  
Zhi Ge ◽  
Wu Li ◽  
Hai Fang Zhou ◽  
Da Wei Huang
Keyword(s):  
Concrete Strength ◽  
Concrete Pavement ◽  
Strength Development ◽  
Concrete Pavements ◽  
Strength Gain ◽  
Rapid Repair ◽  
Calcium Sulfoaluminate ◽  
Bonding Performance ◽  
Short Period ◽  
Concrete Cylinders

The efficient rapid repair for the distressed concrete pavement requires a rapid setting material that can be placed, cured, and opened to the traffic in short period. Normally, the time of the traffic open is determined by the concrete strength gain in the early hours. Meanwhile, the strength development and thermal and shrinkage properties of the concrete affect the structural and bonding performance of the repaired pavement. Type Ⅲ cement and Calcium Sulfoaluminate (CSA) cement are categorized as the rapid set cement (RSC) and are the most widely used as the cementitious material for the concrete structure rapid repair. The compressive strength of the RSC concrete cylinders with different mix proportions had been tested to obtain a strength gain guide for the rapid repair construction. Coefficient of the thermal expansion and shrinkage of the concrete were experimented. The results show that the RSC cement concretes are steady and can meet the requirement of the concrete pavement repair.

Strength Development of Concrete with Proto-Machine-Made Sand

2010 ◽  
Vol 152-153 ◽  
pp. 1479-1482 ◽  
Author(s):  
Feng Lan Li ◽  
Qian Zhu
Keyword(s):  
Grain Size ◽  
Compressive Strength ◽  
Production Technology ◽  
Concrete Strength ◽  
Strength Development ◽  
Test Results ◽  
Mass Content ◽  
Limit Value ◽  
Compressive Strength Of Concrete ◽  
Powder Content

The proto-machine-made sand is a new artificial material for environmental protection with grain size smaller than 5 mm made of water cleaned crushed stones or gravels broken and separated by machines, in which the stone powder maintains as prototype and certain content by improving the production technology. The paper introduces a series of test results of grade C50 concrete mixed by proto-machine-made sand with stone powder in mass content of 3 %, 7 % and 13 %. Based on the cubic compressive strength of concrete at different ages of 3 d, 4 d, 7 d, 14 d, 28 d, 56 d, 90 d, 120 d, 150 d and 180 d, the developing regularities of strength affected by the content of stone powder are analyzed, the formula for predicting the cubic compressive strength of concrete at any ages is proposed. It is proved that the effect of stone-powder in proto-machine-made sand on concrete strength is virtually different from that of the stone powder mixed with powdered mud in ordinary machine-made sand, and the limit value of stone powder content lower than 5 % is not suitable to proto-machine-made sand for mixing concrete with grade of C50.

Compressive Strength Development of High-Strength Concrete under Different Curing Temperatures

2014 ◽  
Vol 905 ◽  
pp. 195-198 ◽  
Author(s):  
Keun Hyeok Yang ◽  
Jae Sung Mun ◽  
Jae Eun Jeong
Keyword(s):  
Compressive Strength ◽  
High Strength Concrete ◽  
High Strength ◽  
Relative Strength ◽  
Curing Temperature ◽  
Strength Development ◽  
Strength Gain ◽  
Strength Concrete ◽  
Compressive Strength Development ◽  
Measured Strength

The present study examined the in-place strength of high-strength concrete based on the relative strength-maturity relationship. The measured strength gain of high-strength concrete was compared with the predictions obtained from the modified maturity function to consider the offset maturity and the insignificance of subsequent curing temperature after an age of 3 days on later strength of concrete. This study demonstrates that the compressive strength gain of concrete cured at the reference temperature (20°C) for an early age of 3 days is little affected by the subsequent curing temperature histories.

scholarly journals Effects of Fly Ash on Mechanical Properties of Concrete

2018 ◽  
Vol 8 (2) ◽  
pp. 35-40 ◽  
Author(s):  
Masoud Zabihi-Samani ◽  
Seyed Payam Mokhtari ◽  
Farzaneh Raji
Keyword(s):  
Fly Ash ◽  
Transport Properties ◽  
Carbon Dioxide Emissions ◽  
Recycled Concrete ◽  
Curing Temperature ◽  
Strength Development ◽  
Concrete Aggregate ◽  
Test Results ◽  
Recycled Concrete Aggregate ◽  
Low Carbon

Abstract Cement is a common and widespread building material over the world. Similarly, carbon dioxide emissions have been significantly increased due to cement production. Alternative low-carbon binders rather than cement have been progressively sought in recent years. Fly ash was found as an available option, since it is being largely disposed annually as a waste material. In this research several studies have been reviewed and recent applications of fly ash on concrete specification, including strength and fracture toughness of green concrete have been perused. Furthermore, transport properties of high volume fly ash after exposure to high temperature and influence of curing temperature on strength development of fly ash-recycled concrete aggregate blends have been investigated. The investigated test results showed that the properties of composites incorporating fly ash depend on the age of the concrete. Test results also revealed that transport properties of concrete increased notably after exposure to 400cº and the results achieved on fly ash-recycled concrete aggregate led to the conclusion that 15% FA is the optimum blend for road stabilization applications.

Heat Curing Efficiency Estimation of Concrete with Superplastificators on Polycarboxylates Basis

2019 ◽  
Vol 974 ◽  
pp. 231-236
Author(s):  
Lubov I. Kastornykh ◽  
I.V. Trischenko ◽  
A.V. Kakljugin ◽  
D.R. Shershen
Keyword(s):  
Concrete Strength ◽  
Quality Parameters ◽  
Curing Temperature ◽  
Strength Development ◽  
Curing Conditions ◽  
Heat Curing ◽  
Mechanical And Physical Properties ◽  
Temperature Mode ◽  
Temperature Heat ◽  
Efficiency Estimation

The influence of superplastificators on polycarboxylates basis upon forming concrete mechanical and physical properties was estimated under heat curing. Heat curing is most effective for rapid concrete hardening. But simultaneously with concrete strength development heat curing may cause destruction, decreasing the most important concrete properties. It was established that steam cured self-compacting concrete with superplastificators on polycarboxylates basis is most effective at low temperature heat curing conditions. The rational concrete heat curing temperature mode should be chosen according to quality parameters estimated during experiments.

scholarly journals Nondestructive Wireless Monitoring of Early-Age Concrete Strength Gain Using an Innovative Electromechanical Impedance Sensing System

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
C. P. Providakis ◽  
E. V. Liarakos ◽  
E. Kampianakis
Keyword(s):  
Concrete Strength ◽  
Strength Development ◽  
Early Age ◽  
Strength Gain ◽  
Impedance Sensing ◽  
Electromechanical Impedance ◽  
Sensing System ◽  
Cracking Control ◽  
Wireless Usb ◽  
Early Age Concrete

Monitoring the concrete early-age strength gain at any arbitrary time from a few minutes to a few hours after mixing is crucial for operations such as removal of frameworks, prestress, or cracking control. This paper presents the development and evaluation of a potential active wireless USB sensing tool that consists of a miniaturized electromechanical impedance measuring chip and a reusable piezoelectric transducer appropriately installed in a Teflon-based enclosure to monitor the concrete strength development at early ages and initial hydration states. In this study, the changes of the measured electromechanical impedance signatures as obtained by using the proposed sensing system during the whole early-age concrete hydration process are experimentally investigated. It is found that the proposed electromechanical impedance (EMI) sensing system associated with a properly defined statistical index which evaluates the rate of concrete strength development is very sensitive to the strength gain of concrete structures from their earliest stages.

Variasi Penambahan Sika Cim Dan Fiber Kawat Pada Beton Mutu Fc’ 30 Mpa

2018 ◽  
Vol 9 (2) ◽  
pp. 67-73
Author(s):  
M Zainul Arifin
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Curing Temperature ◽  
Test Results ◽  
Concrete Compressive Strength ◽  
Normal Concrete ◽  
Astm Method ◽  
Additive Type ◽  
Composition Variation ◽  
Compressive Strength Of Concrete

This research was conducted to determine the value of the highest compressive strength from the ratio of normal concrete to normal concrete plus additive types of Sika Cim with a composition variation of 0.25%, 0.50%, 0.75%, 1.00%, 1.25%, 1 , 50% and 1.75% of the weight of cement besides that in this study also aims to find the highest tensile strength from the ratio of normal concrete to normal concrete in the mixture of sika cim composition at the highest compressive strength above and after that added fiber wire with a size diameter of 1 mm in length 100 mm with a ratio of 1% of material weight. The concrete mix plan was calculated using the ASTM method, the matrial composition of the normal concrete mixture as follows, 314 kg / m3 cement, 789 kg / m3 sand, 1125 kg / m3 gravel and 189 liters / m3 of water at 10 cm slump, then normal concrete added variations of the composition of sika cim 0.25%, 0.50%, 0.75%, 1.00%, 1.25%, 1.5%, 1.75% by weight of cement and fiber, the tests carried out were compressive strength of concrete and tensile strength of concrete, normal maintenance is soaked in fresh water for 28 days at 30oC. From the test results it was found that the normal concrete compressive strength at the age of 28 days was fc1 30 Mpa, the variation in the addition of the sika cim additive type mineral was achieved in composition 0.75% of the cement weight of fc1 40.2 Mpa 30C. Besides that the tensile strength test results were 28 days old with the addition of 1% fiber wire mineral to the weight of the material at a curing temperature of 30oC of 7.5%.

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