Effect of Water-Cement Ratio on Carbonation and Steel-Corrosion Resistance of Recycled Concrete

2012 ◽  
Vol 174-177 ◽  
pp. 1552-1557 ◽  
Author(s):  
Ya Li Sun ◽  
Jin Song Zhu
Keyword(s):  
Compressive Strength ◽  
Concrete Strength ◽  
Steel Corrosion ◽  
Recycled Concrete ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Ordinary Concrete ◽  
Steel Bar ◽  
Steel Corrosion Resistance ◽  
Concrete Cube

This paper studies the effects of different water-cement ratio on recycled concrete strength, anti-carbonation capability, and protecting reinforce steel bar capability. Select the water-cement ratio 0.6,0.55,0.5,0.45,0.4 five cases of the pilot study.It shows that: recycled concrete cube compressive strength, anti-carbonation capacity and protecting reinforce steel bar capability are less than ordinary concrete.

Effect of Admixed Recycled Aggregate on Properties of Recycled Concrete

2012 ◽  
Vol 174-177 ◽  
pp. 743-746
Author(s):  
Ya Jun Zhao ◽  
Ying Gao ◽  
Li Li He
Keyword(s):  
Compressive Strength ◽  
Design Method ◽  
Orthogonal Design ◽  
Plain Concrete ◽  
Recycled Concrete ◽  
Recycled Aggregate ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Influence Of Water ◽  
The Impact

The mixture proportion of recycled concrete was discussed by orthogonal design method. The influence of water-cement ratio, recycled aggregate quantity on workability, cube compressive strength of recycled concrete was analyzed. The experimental results indicated that，Recycled concrete mix proportion design should consider the impact of the water absorption of recycled aggregate. Unit water amount of recycled concrete should be plain concrete unit water consumption and recycled aggregate additional amount of water. Sand ratio should increase in the corresponding ordinary aggregate concrete sand ratio on the basis of 1 to 3 percent. When the water-cement ratio is 0.36 and construction waste content of 40% slag content of 20%, 28d compressive strength of concrete is 48.1MPa, slightly higher than the reference concrete (48.0MPa).

Effect of Recycled Coarse Aggregate on Recycled Concrete Properties and Study of Optimum Mixture Ratio

2014 ◽  
Vol 487 ◽  
pp. 84-89
Author(s):  
Hai Long Ning ◽  
Wen Feng Zhao ◽  
Jian Liu ◽  
Shao Peng Jiao ◽  
Yi Xin Wang
Keyword(s):  
Mechanical Properties ◽  
Coarse Aggregate ◽  
Concrete Strength ◽  
Recycled Concrete ◽  
Replacement Rate ◽  
Conventional Concrete ◽  
Mixture Ratio ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Recycled Coarse Aggregate

To study the effect of recycled coarse aggregate, water-cement ratio and mixture ratio on the physico-mechanical properties of recycled concrete, determine the finial optimum mixture ratio and physico-mechanical properties of recycled concrete with the optimum mixture ratio, physico-mechanical tests are done on recycled concrete and conventional concrete. Results show that with the replacement rate increasing of recycled coarse aggregate, the compressive strength and splitting tensile strength of recycled concrete increase and then decrease. It is feasible to develop the concrete with 100% replacement rate of recycled coarse aggregate. With an increase of recycled coarse aggregate replacement rate, dry shrinkage ratio of concrete increases gradually, but the increasing range has little effect on the concrete. The concrete strength of 28 days is linear with water-cement ratio with the correlation coefficient is 0.98763. Taking appropriate mix design, the physico-mechanical properties of recycled concrete will surpass or be equivalent to those of conventional concrete. Recycled concrete of the optimum mixing rate is the high strength with lower brittleness.

Research on Mechanical Properties of Polymer Regenerative Concrete

2017 ◽  
Vol 873 ◽  
pp. 147-152
Author(s):  
Wei Liu ◽  
Shi Min Zhang ◽  
Hong Hao Ying ◽  
Nan Zhao
Keyword(s):  
Compressive Strength ◽  
Performance Test ◽  
Failure Process ◽  
Testing Machine ◽  
Concrete Block ◽  
Test Methods ◽  
Recycled Concrete ◽  
Ordinary Concrete ◽  
Strength Failure ◽  
Concrete Cube

This paper designed and completed the different polymer dosage of recycled concrete, was prepared by adding amount was 7%, 14%, 21%, 14% styrene butadiene latex recycled concrete, recycled rubber powder recycled concrete and ordinary concrete block, the cube compressive strength and damping performance test. The cube compressive strength of concrete test according to the ordinary concrete mechanics performance test methods, specimen is 150×150×150 mm cube specimens, pressure testing machine loading speed is 0.5 MPa per second. The concrete damping performance test is carried out according to the free attenuation method, with the hammer vibration test device, the test piece is T type. Based on the damage form of specimens, the compressive strength and damping performance analysis, and compared with ordinary concrete as the benchmark analysis test results show that the polymer recycled concrete cube compressive strength failure process and failure pattern basic consistent with common concrete; In the water/cement ratio, sand ratio, and amount of material per unit volume is the same, under the condition of polymer recycled concrete cube compressive strength is lower than normal concrete, damping performance is higher than that of ordinary concrete, the compressive strength is inversely proportional to the damping sexual relations.

The Effect of Water-Cement Ratio and Curing Age on the Strength of Recycled Concrete

2011 ◽  
Vol 217-218 ◽  
pp. 740-745
Author(s):  
Xue Bing Zhang ◽  
Chen Gang Kuang ◽  
Zhi Fang
Keyword(s):  
Growth Rate ◽  
Coarse Aggregate ◽  
Recycled Concrete ◽  
Empirical Formulas ◽  
Natural Sand ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Ordinary Concrete ◽  
Effect Of Water ◽  
Curing Age

The effect of water-cement ratio and curing age on the strength of recycled concrete was studied by experiment with the combination of the recycled coarse aggregate adding natural sand. The results showed that with the increase of curing age, the greater the water-cement ratio is, the smaller the strength growth rate is; the smaller the water-cement ratio is, the greater the strength growth rate is. There is a relatively larger increase in the growth rate of 90d strength than 28d’, which is significantly higher than that of the ordinary concrete. The linear relationship between water-cement ratio and strength of recycled concrete is worse than that of ordinary concrete. Under the same water-cement ratio and curing age, the strength of recycled concrete is lower than that of ordinary concrete, and the empirical formulas between the strength of 28d and 7d, 90d and 28d were obtained.

Experimental Study on Strength of Recycled Concrete

2013 ◽  
Vol 357-360 ◽  
pp. 1282-1285
Author(s):  
Hai Yong Cai ◽  
Li Bin Fu ◽  
Ling Bo Dang
Keyword(s):  
Mechanical Properties ◽  
Experimental Study ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Great Influence ◽  
Recycled Concrete ◽  
Replacement Ratio ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Concrete Mechanical Properties

Influence of replacement ratio and water-cement ratio on the recycled concrete mechanical properties were analyzed by testing the compressive strength and tensile strength of the recycled concrete. Results show that the mechanical properties of recycled concrete, compared with common concrete, can meet the requirements of the project. Water-cement ratio has great influence on compressive strength and tensile strength, replacement ratio has obvious influence on compressive strength but little on tensile.

Experimental Study on the Strength and Damping Properties of Polymer Recycled Concrete

2018 ◽  
Vol 1145 ◽  
pp. 117-122 ◽  
Author(s):  
Wei Liu ◽  
Jian Xin Zhou ◽  
Feng Zhang ◽  
Guo Tai Li
Keyword(s):  
Compressive Strength ◽  
Performance Test ◽  
Failure Process ◽  
Testing Machine ◽  
Concrete Block ◽  
Test Methods ◽  
Recycled Concrete ◽  
Ordinary Concrete ◽  
Strength Failure ◽  
Concrete Cube

This paper designed and completed the different polymer dosage of recycled concrete, was prepared by adding amount was 7%, 14%, 21%, 14% styrene butadiene latex recycled concrete, recycled rubber powder recycled concrete and ordinary concrete block, the cube compressive strength and damping performance test. The cube compressive strength of concrete test according to the ordinary concrete mechanics performance test methods, specimen is 150×150×150 mm cube specimens, pressure testing machine loading speed is 0.5 MPa per second. The concrete damping performance test is carried out according to the free attenuation method, with the hammer vibration test device, the test piece is T type. Based on the damage form of specimens, the compressive strength and damping performance analysis, and compared with ordinary concrete as the benchmark analysis test results show that the polymer recycled concrete cube compressive strength failure process and failure pattern basic consistent with common concrete. In the water/cement ratio, sand ratio, and amount of material per unit volume is the same, under the condition of polymer recycled concrete cube compressive strength is lower than normal concrete, damping performance is higher than that of ordinary concrete, the compressive strength is inversely proportional to the damping sexual relations.

Effect of nanocomposite slurry on strength development of fully recycled aggregate concrete

2021 ◽  
pp. 136943322199248
Author(s):  
Tao Meng ◽  
Song-lin Yu ◽  
Huadong Wei ◽  
Sheng Zhu
Keyword(s):  
Compressive Strength ◽  
Recycled Concrete ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Strength Development ◽  
Aggregate Concrete ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Natural Aggregate ◽  
Enhancement Method

Recycled concrete has been widely used in construction because of the gradual shortage of natural aggregate resources and the large amount of construction waste. In this study, concrete with 100% recycled aggregate was prepared, and its properties, microtopography, and potential enhancement method were investigated. The results indicated that the mechanical properties of the fully recycled aggregate concrete (FRC) were significantly inferior to the natural aggregate concrete. The compressive strength of the FRC with a water-cement ratio of 0.6 was noticeably improved by spraying a nanocomposite slurry on recycled aggregate, whereas this had little influence when the water-cement ratio was 0.3. The compressive strength of the FRC with a water-cement ratio of 0.3 could be improved by mixing with strengthening materials. The best improvement in the compressive strength of the concrete was observed at 28 days because a membrane covered the surface of the aggregate, creating a bond between the aggregate and cement, filling the pores between them, and compacting the concrete. This paper reports a prospective method for improving the properties of FRC, which will promote the application of recycled aggregate in industry.

scholarly journals Investigations of the structural characteristics of concrete produced from recycled aggregates at varying water/cement ratios

2020 ◽  
Vol 39 (3) ◽  
pp. 640-646
Author(s):  
A.W. Otunyo ◽  
B.G. Jephter
Keyword(s):  
Compressive Strength ◽  
Structural Characteristics ◽  
Absorption Capacity ◽  
Recycled Concrete ◽  
Recycled Aggregates ◽  
Concrete Aggregate ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Natural Aggregate ◽  
Natural Aggregates

The paper tried to investigate the structural characteristics of concrete produced by partially replacing natural aggregates with recycled aggregates at varying water/cement ratios. The study is basically a laboratory experimental study. Water/cement ratio component of the concrete were varied at 0.40, 0.45, 0.50, 0.55, 0.60; while the natural aggregate was partially replaced with RCA of 0%, 15%, 30%, 45%, 60%, 75% and 90% for concrete productions for 7, 14 and 28 days structural characteristics. The densities, water absorption capacity and Compressive Strength of these concretes were determined. The results were presented in graphs and Tables. Results of the study indicate an increased compressive strength at low percentage of RCA and water /cement ratio values. There is a marginal difference between compressive strength of normal concrete and concrete produced by partial RCA of 15% replacement at 0.4 w/c ratio. Keywords: recycled concrete aggregate, natural aggregate, compressive strength, water/ cement ratio and natural aggregate concrete.

Research on the Strength of High-Strength Steel Slag Concrete with Skeleton Coarse Aggregate Gradation

2013 ◽  
Vol 671-674 ◽  
pp. 1918-1922
Author(s):  
Yi Zhou Zhuang ◽  
Er Bu Tian ◽  
Yue Zong Lian
Keyword(s):  
Compressive Strength ◽  
High Strength Concrete ◽  
Coarse Aggregate ◽  
Concrete Strength ◽  
Steel Slag ◽  
High Strength ◽  
Test Results ◽  
Aggregate Gradation ◽  
Cement Ratio ◽  
Water Cement Ratio

Generally the high density in high-strength concrete results in high strength, and so people often mix superplasticizer and particulate to increase the density of concrete, but ignoring the effect of coarse aggregate gradation on concrete strength. Referring to several Gradation Theories, this paper selects the coarse aggregate gradation with skeleton, uses uniform design method to test the compressive strength of high-strength concrete, and analyses the test results. It can be known from the test results of 7d and 28d concrete specimen that the concrete strength decreases linearly with water-cement ratio and sand ratio; The 7d’s concrete strength has higher variability due to low water-cement ratio with superplasticizer; The coarse aggregate skeleton is interfered by the increase of steel slag and sand rate, and the concrete strength decreases with limited cement paste. Furthermore, the steel slag with less than 30% addition has little effect on concrete strength and it can increase the cement’s possibility of contacting to water, and reduce the amount of cement without lowering the concrete strength. The influential degree on the compressive strength of concrete is followed by ascending sequence of steel slag content, sand ratio and water-cement.

scholarly journals Bond between Steel Reinforcement Bars and Seawater Concrete

2020 ◽  
Vol 6 ◽  
pp. 61-68
Author(s):  
Adnan Adnan ◽  
Herman Parung ◽  
M. W. Tjaronge ◽  
Rudy Djamaluddin
Keyword(s):  
Compressive Strength ◽  
Bonding Strength ◽  
High Performance Concrete ◽  
Infrastructure Development ◽  
Normal Concrete ◽  
Cement Ratio ◽  
Water Cement Ratio ◽  
Composite Cement ◽  
Steel Bar ◽  
Remote Islands

In order to promote sustainable development in the remote islands this present research attempted to study the suitability of seawater, that available abundantly surrounding the remote islands with Portland composite cement (PCC) and crushed river stones to produce concrete. This research aims to utilize seawater, and Portland composite cement (PCC) to produce high-performance concrete in order to eliminate the main problems of clean water shortage in the low land areas and the remote islands. Infrastructure development can be sustained through the effective use of natural available local materials on the remote islands. The method used in this research is an experimental method in the laboratory. Two variations of concrete were made using freshwater and seawater, respectively as a mixing material with a water to cement ratio (w/c) of 0.55. The evaluation result on concrete compressive strength and bond strength of seawater concrete were discussed. Experimental results showed the compressive strength of the seawater concrete is lower by 6.26% as compared to the normal concrete at water-cement ratio (w/c) of 0.55. In addition, the bonding strength of steel bar embedded in seawater concrete is lower by 4.34% as compared to the bonding strength of steel bar embedded in normal concrete at water-cement ratio (w/c) of 0.55. Doi: 10.28991/cej-2020-SP(EMCE)-06 Full Text: PDF

Sign in / Sign up

Export Citation Format

Share Document