scholarly journals Influence of Mixing Procedures, Rubber Treatment, and Fibre Additives on Rubcrete Performance

2019 ◽  
Vol 3 (2) ◽  
pp. 41 ◽  
Author(s):  
Osama Youssf ◽  
Reza Hassanli ◽  
Julie E. Mills ◽  
William Skinner ◽  
Xing Ma ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Photoelectron Spectroscopy ◽  
Tap Water ◽  
Mixing Time ◽  
Laboratory Research ◽  
Strength Increase ◽  
Sodium Bisulphite ◽  
Rubber Particles ◽  
Pre Treatment

This research extensively investigates how to enhance the mechanical performance of Rubcrete, aiming to move this type of concrete from the laboratory research level to a more practical use by the concrete industry. The effects of many different mixing procedures, chemical pre-treatments on the rubber particles, and the use of fibre additives, have been investigated for their impact upon Rubcrete workability, compressive strength, tensile strength, and flexural strength. The mixing procedure variables included mixing time and mixing order. The rubber pre-treatments utilized chemicals such as Sodium Hydroxide (NaOH), Hydrogen Peroxide (H2O2), Sulphuric acid (H2SO4), Calcium Chloride (CaCl2), Potassium Permanganate (KMnO4), Sodium Bisulphite (NaHsO3), and Silane Coupling Agent. Soaking rubber particles in tap water, or running them through water before mixing, were also tried as a pre-treatment of rubber particles. In addition, the effects of fibre additives such as steel fibres, polypropylene fibres, and rubber fibres, were assessed. X-ray photoelectron spectroscopy (XPS) analysis was utilised to examine some of the pre-treated rubber particles. The results showed that doubling the net mixing time of all mix constituents together enhanced the Rubcrete slump by an average of 22%, and the compressive strength by up to 8%. Mixing rubber with dry cement before adding to the mix increased the compressive strength by up to 3%. Pre-treatment using water was more effective than other chemicals in enhancing the Rubcrete workability. Regardless of the treatment material type, the longer the time of the treatment, the more cleaning of rubber occurred. Significant Rubcrete flexural strength increase occurred when using 1.5% fibre content of both steel fibre and polypropylene fibre.

Effect of using magnetic water on the mechanical properties of concrete exposed to elevated temperature

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Wasim Barham ◽  
Ammar AL-Maabreh ◽  
Omar Latayfeh
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Elevated Temperature ◽  
Flexural Strength ◽  
Tap Water ◽  
Splitting Tensile Strength ◽  
Content Type ◽  
Normal Water ◽  
Magnetic Water

PurposeThe influence of using magnetic water instead of tap water in the mechanical properties of the concrete exposed to elevated temperatures was investigated. Two concrete mixes were used and cast with the same ingredients. Tap water was used in the first mix and magnetic water was used in the second mix. A total of 48 specimens were cast and divided as follows: 16 cylinders for the concrete compressive strength test (8 samples for each mix), 16 cylinders for the splitting tensile strength (8 specimens for each mix) and 16 beams to test the influences of magnetized water on the flexural strength of concrete (8 specimens for each mixture). Specimens were exposed to temperatures of (25 °C, 200 °C, 400 °C and 600 °C). The experimental results showed that magnetic water highly affected the mechanical properties of concrete. Specimens cast and curried out with magnetic water show higher compressive strength, splitting tensile strength and flexural strength compared to normal water specimens at all temperatures. The relative strength range between the two types of water used was 110–123% for compressive strength and 110–133% for splitting strength. For the center point loading test, the relative flexural strength range was 118–140%. The use of magnetic water in mixing concrete contribute to a more complete hydration process.Design/methodology/approachExperimental study was carried out on two concrete mixes to investigate the effect of magnetic water. Mix#1 used normal water as the mixing water, and Mix#2 used magnetic water instead of normal water. After 28 days, all the samples were taken out of the tank and left to dry for seven days, then they were divided into different groups. Each group was exposed to a different temperature where it was placed in a large oven for two hours. Three different tests were carried out on the samples, these tests were concrete compressive strength, flexural strength and splitting tensile strength.FindingsExposure of concrete to high temperatures had a significant influence on concrete mechanical properties. Specimens prepared using magnetic water showed higher compressive strength at all temperature levels. The use of magnetic water in casting and curing concrete can increase the compressive strength by 23%. Specimens prepared using magnetic water show higher splitting tensile strength at all temperatures up to 33%. The use of magnetic water in casting and curing can strengthen and increase concrete resistance to high temperatures, a significant enhancement in flexural strength at all temperatures was found with a value up to 40%.Originality/valuePrevious research proved the advantages of using magnetic water for improving the mechanical properties of concrete under normal conditions. The potential of using magnetic water in the concrete industry in the future requires conducting extensive research to study the behavior of magnetized concrete under severe conditions to which concrete structures may be subjected to. These days, there are attempts to obtain stronger concrete with high resistance to harsh environmental conditions without adding new costly ingredients to its main mixture. No research has been carried out to investigate the effect of magnetic water on the mechanical properties of concrete exposed to elevated temperature. The main objective of this study is to evaluate the effect of using magnetic water on the mechanical properties of hardened concrete subjected to elevated temperature.

Experimental Study on Ratio of Bending-Compressive Strength of the Crumb Rubber Concrete Modified by Latex

2014 ◽  
Vol 941-944 ◽  
pp. 761-764
Author(s):  
Wei Li ◽  
Zhen Huang ◽  
Xiao Chu Wang ◽  
Zi Sheng Zang
Keyword(s):  
Mechanical Property ◽  
Experimental Study ◽  
Compressive Strength ◽  
Surface Modification ◽  
Flexural Strength ◽  
Crumb Rubber ◽  
Interface Effect ◽  
Rubber Particles ◽  
Crumb Rubber Concrete ◽  
Rubber Concrete

The cementitiousness between rubber particles and cement-based material could be raised because of the surface modification of rubber,thus enhance the mechanical property of crumb rubber concrete and improve the interface effect of rubber particles.We had researched the change regulation about the ratio of bending-compressive strength of the crumb rubber concrete modified by latex,the concrete with various quantity of rubber,under the condition dosage of latex is 0.5% of cement quality.The result of experimental prove that,compressive strength, splitting tensile and flexural strength could be enhanced because of latex injecting,and the ratio of bending-compressive strength could be enhanced at the same time.

scholarly journals Developing a forecasting model of concrete compressive strength using relevance vector machines

2014 ◽  
Vol 3 (2) ◽  
pp. 224 ◽  
Author(s):  
Mohammad Awwad
Keyword(s):  
Compressive Strength ◽  
Early Stage ◽  
Mixing Time ◽  
Relevance Vector Machine ◽  
Strength Increase ◽  
Concrete Compressive Strength ◽  
Relevance Vector Machines ◽  
Vector Machines ◽  
Strength Material ◽  
Cement Mixture

We analyze results of two experiments that tested effect of adding Silica on the compressive strength of concrete at early stage and after long period. The two experiments evaluated different silica/cement ratios for different mixing periods. Adding Silica to concrete mix produce high early strength material which is highly desirable in airports and highways. More than 90 samples of different silica/cement ratios are tested for compressive strength at 3 and 28 days. Test results showed high early up to 60 MPa. Strength increase is proportional with the increase of silica/cement ratio and mixing time with maximum at ratio of 15/100 and 30 minutes mixing time. A relevance Vector Machine (RVM) model is developed to predict concrete compressive strength using concrete mixture inputs information. RVM model predictions matched experimental data closely. The developed model can be used to predict compressive strength in future periods based on initial information related to cement mixture. Keywords: Relevance Vector Machine, Silicate Percent, Prediction Model, Milling Time, Compressive Strength, Concrete.

Experimental Study on Proportion of Tensile Strength and Compressive Strength of the Crumb Rubber Concrete Modified by Latex

2014 ◽  
Vol 919-921 ◽  
pp. 1916-1919
Author(s):  
Wei Li ◽  
Zhen Huang ◽  
Xiao Chu Wang ◽  
Zi Sheng Zang
Keyword(s):  
Mechanical Property ◽  
Experimental Study ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Surface Modification ◽  
Flexural Strength ◽  
Crumb Rubber ◽  
Rubber Particles ◽  
Crumb Rubber Concrete ◽  
Rubber Concrete

The cementitiousness between rubber particles and cement-based material could be raised because of the surface modification of rubber,thus enhance the mechanical property of crumb rubber concrete and improve the interface effect of rubber particles.We had researched the change regulation of the ratio between tensile strength and compressive strength of the Crumb Rubber Concrete Modified by latex,the concrete with various quantity of rubber,under the condition Dosage of latex is 0.5% of cement quality.The result of Experimental prove that,compressive strength, splitting tensile and flexural strength could be enhanced because of latex injecting,and the ratio between tensile strength and compressive strength could be enhanced at the same time.

Research on Alkali-Activator and its Effects on Mechanical Properties of Slag-Based Geopolymer at early Age

2014 ◽  
Vol 556-562 ◽  
pp. 399-403 ◽  
Author(s):  
Li Shun Chen ◽  
Xiao Chen ◽  
Jian Tong Xu ◽  
Zhong Yang
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Compression Strength ◽  
Downward Trend ◽  
Early Age ◽  
Strength Increase ◽  
Apparent Increase ◽  
Alkali Activator

This report studied the influence of effects such as type, modulus, dosage of the alkali-activator on mechanical properties of slag-based geopolymer. The analyzing results indicate that compare to the Na2SiO3, K2SiO3has significant activate effects on slag-based geopolymer. The modulus and dosage have obvious significance on early compression strength of slag-based geopolymer. With the increase of modulus, its early compression strength has apparent increase. With the increase of dosage, its early compression strength increase firstly and then decrease. When the dosage is 12%, the compression strength of the material is highest. The change of modulus and dosage of the alkali-activator has little influence on flexural strength of slag-based geopolymer. With the increase of dosage, its ratio of flexural to compressive strength has a downward trend. And the material brittleness addition.

Effect on Mechanical Properties of Rubberized Concrete due to Pretreatment of Waste Tire Rubber with NaOH

2013 ◽  
Vol 357-360 ◽  
pp. 897-904 ◽  
Author(s):  
Qing Wen Ma ◽  
Jin Chao Yue
Keyword(s):  
Compressive Strength ◽  
Elastic Modulus ◽  
Flexural Strength ◽  
Strain Ratio ◽  
Zinc Stearate ◽  
Ultimate Strain ◽  
Rubberized Concrete ◽  
Volume Percentage ◽  
Strength Tests ◽  
Rubber Particles

Rubber particles were dipped into NaOH solution in order to wipe the zinc stearate generated in the process of preparation of rubber power. Rubber with different particle diameters and mixing amount (sand replaced in equal volume percentage) was adopted to produce rubberized concrete specimens. A series of tests including compressive strength tests, flexural strength tests, elastic modulus tests and ultimate strain ratio tests were done respectively. The results of tests showed that the value of the compressive strength, flexural strength and elastic modulus decreased with the increase of the mixing amount of rubber, while the decrease amplitude was different from each other. The value of ultimate strain increased a little and the ability of toughness and deformation of rubberized concrete were enhanced obviously through dipping rubber particles into NaOH solution.

Study on the Influence of Polypropylene Fiber and SBR Latex on the Static Strength of Rubber Mortar

2013 ◽  
Vol 318 ◽  
pp. 297-302 ◽  
Author(s):  
Shao Qin Ruan ◽  
Cheng Yuan Lin ◽  
Si Xian Jiang
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Polypropylene Fiber ◽  
Static Strength ◽  
Rubber Particles ◽  
Better Than

This paper deals with the investigation of the static strength of rubber mortar with the inclusion of two macromolecules: SBR (butylbenzene) latex and PP (polypropylene) fiber. The rubber mortar were produced with the inclusion of SBR latex and PP fiber. The characteristics were performed by testing the compressive strength, flexural strength and the C/F (it refers to the ratio of compressive to flexural strength). The results proved that compared to conventional mortar and rubber mortar, the C/F (lower C/F means better flexibility) of SBR latex modified rubber mortar decreased and its flexibility significantly enhanced. The rubber mortar with 2.5% P/C (it refers to the ratio of polymer-cement) of SBR latex performed best in flexibility and the flexibility of rubber mortar with 30% rubber particles proportion was better than the 20% counterparts. The C/F of PP fiber and SBR latex modified rubber mortar was minimum with 7.5% P/C (20% rubber particles proportion groups) and 2.5% P/C of SBR latex (30% rubber particles proportion groups).

1 Year Long Term on Strength Properties of Pozzolanics Local Soil Bricks

2011 ◽  
Vol 399-401 ◽  
pp. 1381-1385
Author(s):  
Weerapol Namboonruang ◽  
Rattanakorn Rawangkul ◽  
Wanchai Yodsudjai ◽  
Nutthanan Suphadon
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Strength Properties ◽  
Modulus Of Rupture ◽  
Strength Increase ◽  
Soil Cement ◽  
Local Soil ◽  
Rupture Properties

This work emphasizes on the study of Pozzolanics Local Soil Brick properties. The compressive strength and flexural strength on modulus of rupture properties are investigated. At the ratio of 5% Portland cement type 1 and 30% fly ashes by weight at water powder ratio (w/p) 0.3525. This brick is called as Pozzolanics soil bricks. Their properties are compared to soil cement bricks (RCM35) at the age of 3, 7, 14, 28, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330 and 360. Results show that the compressive strength and flexural strength increase with increasing curing time. The compressive strength and the flexural strength at 360 day curing times increases as 41.83% and 43.77%, respectively compared at 28 day curing times. Similar to soil cement bricks, the compressive strength and flexural strength of Pozzolanics soil bricks increase as 20.80% and 11.94% respectively compared between 360 day and 28 day curing times. However, comparing to RCM35 at 360 days the compressive strength and the flexural strength are lower as 60.43% and 4.90 times respectively.

Mechanical Properties and Microstructures of Cement Mortar Modified with Styrene-Butadiene Polymer Emulsion

2010 ◽  
Vol 168-170 ◽  
pp. 190-194 ◽  
Author(s):  
Zhen Jun Wang ◽  
Rui Wang ◽  
Yu Bin Cheng
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Cement Mortar ◽  
Strength Increase ◽  
Polymer Emulsion ◽  
Cement Ratio ◽  
Cement Mortars ◽  
Water To Cement Ratio ◽  
Styrene Butadiene

In this paper, styrene-butadiene polymer emulsion SD622S was adopted to modify cement mortar; mechanical properties of cement mortars were studied and microstructures was analyzed by means of Scanning Electron Microscope (SEM) and Specific Surface Area & Pore Distribution Analyzer. The results show that in contrast to ordinary cement mortar, if water to cement ratio (W/C) is constant, compressive strength of modified cement mortar can decrease, while flexural strength and toughness, ratio of compressive strength to flexural strength, increase with the increase of polymer to cement ratio in mass (P/C) at 7 and 28 curing days. With the increase of P/C, net structure made from polymer and cement hydration products is developed and pore whose size is smaller than 200Å begins to increase, which indicates pore diameters in modified cement mortar change to be finer. So microstructures of modified cement mortar become denser and display higher toughness.

Influence of Mixing Time on Workability and Strength Properties of Concrete in Different Consistency

2011 ◽  
Vol 217-218 ◽  
pp. 1224-1228
Author(s):  
Dong Fang ◽  
Ming Kai Zhou ◽  
Hua Gang Wang
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Mixing Time ◽  
Strength Properties ◽  
Stiff System ◽  
Examination Result ◽  
Result Show

A series of experiment based on different mixing time were carried out to investigate the effect of mixing time on slump, modified VC value and strength properties of concrete in different consistency. The flexural strength, compressive strength on the conditions of highly stiff s, stiff and plastic system was studied. The optimized mixing time was determined and its reason was analyzed. The examination result show that the highly stiff concrete have the best performance when the mixing time is at about 120s, the stiff system is at 60s, the plastic system is at 30s.

Sign in / Sign up

Export Citation Format

Share Document