scholarly journals Analysis and Prediction of Compressive Properties for Steel Fiber-and-Nanosilica-Reinforced Crumb Rubber Concrete

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Danying Gao ◽  
Tao Zhang ◽  
Yihong Wang ◽  
Yiming Kong ◽  
Dawei Li ◽  
...  

The disposal of waste tire rubber has gained more attention from the viewpoint of green, environmental protection, and sustainability. Numerous attempts have been stated on the properties of crumb rubber concrete (CRC) and observed that there is a large reduction of compressive strength and elastic modulus of CRC with the increase of the rubber substitution rate. Based on the CRC with the crumb rubber volume content of 5%, the steel fibers and nanosilica were added to CRC to make steel fiber-and-nanosilica-reinforced crumb rubber concrete (SFNS-CRC) in this paper. The effects of the steel fiber volume content and nanosilica content on the compressive properties of SFNS-CRC were studied, including compressive strength, elastic modulus, peak strain, compression toughness, and failure pattern. The test results indicated that the modulus of elasticity and compressive strength of SFNS-CRC have the increasing tendency with the addition of steel fibers and nanosilica. Moreover, the peak strains have a significant increase with the increase of the steel fiber content and nanosilica replacement ratio. The compressive stress-strain curves of SFNS-CRC gradually plump with the increase of the steel fibers and nanosilica. Finally, the prediction formulas for the compressive strength, elastic modulus, and peak strain of SFNS-CRC were set up. A simple predicted model of the stress-strain curve for SFNS-CRC was proposed, which considers the effect of steel fibers and nanosilica.

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Yihong Wang ◽  
Jiawei Chen ◽  
Danying Gao ◽  
E. Huang

Crumb rubber concrete (CRC) is an environment-friendly material using crumb rubber as a composition of cement concrete. It provides an alternative method for recycling of waste tires scientifically. CRC exhibits numerous advantages compared to ordinary concrete. However, the application of CRC is limited due to its low compressive and tensile strengths. This paper puts forward a new modified method by adding steel fibers and nanosilica in CRC. Material properties’ testing of eighteen concrete mixtures was investigated, considering different strength grades of CRC and crumb rubber contents. In addition, four different steel fiber contents (0%, 0.5%, 1.0%, and 1.5%) and three different nanosilica content (0%, 1%, and 2%) were taken into consideration. The brittle failure of the CRC can be improved and the mechanical properties can be enhanced according to the test results. More importantly, the modified CRC with 1.0% steel fiber content has relatively high compressive and splitting tensile strengths. Furthermore, the noncompactness of CRC can be effectively improved by nanosilica, enhancing the efficiency of steel fibers simultaneously. Finally, the failure mechanism of the modified CRC is discussed in this paper.


2014 ◽  
Vol 941-944 ◽  
pp. 761-764
Author(s):  
Wei Li ◽  
Zhen Huang ◽  
Xiao Chu Wang ◽  
Zi Sheng Zang

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.


Geofluids ◽  
2019 ◽  
Vol 2019 ◽  
pp. 1-12 ◽  
Author(s):  
Ronghua Shu ◽  
Tubing Yin ◽  
Xibing Li

Variation in the heating rate due to different geothermal gradients is a cause of much concern in underground rock engineering such as deep sea and underground tunnels, nuclear waste disposal, and deep mining. By using a split Hopkinson pressure bar (SHPB) and variable-speed heating furnace, the dynamic compressive properties of granite were obtained after treatments at different heating rates and temperatures; these properties mainly included the dynamic compressive strength, peak strain, and dynamic elastic modulus. The mechanism of heating rate action on the granite was simultaneously analyzed, and the macroscopic physical properties were discussed. The microscopic morphological features were obtained by scanning electron microscopy (SEM), and the crack propagation was determined by high-speed video camera. The experimental results show that the dynamic compressive strength and elastic modulus both show an obvious trend of a decrease with the increasing heating rate and temperature; the opposite phenomenon is observed for the peak strain. The relationships among the dynamic compressive properties and temperature could be described by the quadratic function. The ductility of granite is enhanced, and the number and size of cracks increase gradually when the heating rate and temperature increase. The microstructure of rock is weakened by the increased thermal stress, which finally affects the dynamic compressive properties of rock.


2014 ◽  
Vol 919-921 ◽  
pp. 1916-1919
Author(s):  
Wei Li ◽  
Zhen Huang ◽  
Xiao Chu Wang ◽  
Zi Sheng Zang

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.


2010 ◽  
Vol 150-151 ◽  
pp. 1176-1183 ◽  
Author(s):  
Mei Zhou ◽  
Xiao Ming Yang ◽  
Kun Song

this paper got the compressive stress-strain fitting curve of crumb rubber plastic concrete, analyzed the influencing factors of elastic modulus of crumb rubber plastic concrete and found the influence law of specimen size and measuring distance to measured value of elastic modulus, through our experiments. The results of our experiments show that the method and operation of experiment strongly influence the measured value of elastic modulus of crumb rubber plastic concrete, but we can use the measures of step loading, screening and fitting curve to get the relatively exact measured value of elastic modulus of plastic concrete. And then, this paper analyzed a 16 sets of uniform experiment results with regression analysis method. As a result, we found the main influencing factors of elastic modulus of crumb rubber concrete are cement mixing amount, crumb rubber mixing amount and product of water-binder ratio and water reducer mixing amount, which the importance of them decreases progressively. Finally, this paper established the prediction equation of elastic modulus of crumb rubber concrete and found the connection of elastic modulus of crumb rubber concrete with specimen size and measuring distance.


2016 ◽  
Vol 680 ◽  
pp. 378-381 ◽  
Author(s):  
Wen Xian Zhu

Considering environmental protection, the application of waste tire is getting thorough and extensive. Basing on the previous research results, the variation principle of ultrasonic velocity and attenuation in concrete with age, the author carries out the application research on predicting 28-daycompressive strength of crumb rubber concrete during early age. Through the regression analysis between the 2-7days ultrasonic parameters (velocity v and/or attenuation A) and the 28-day compressive strength of crumb rubber concrete, it is found that the correlative coefficient is greater than 0.90 and the relative square deviation is less than 15%. So it is practically reasonable to predict 28-day compressive strength of crumb rubber concrete by pre-established regression curves.


2022 ◽  
Vol 2022 ◽  
pp. 1-14
Author(s):  
Qi Li ◽  
Fei Xu ◽  
Hemin Zheng ◽  
Junhao Shi ◽  
Jianyu Zhang

Crumb Rubber Concrete (CRC) can exhibit high freeze-thaw resistance, but its long-term creep behavior under various freeze-thaw conditions remains unclear, which is essential for the safety of pavement engineering in the severe cold zone. In this study, the freeze-thaw effects on the creep behavior of CRC under different stress levels were systematically analyzed by testing the compressive strength, the uniaxial creep under different stress levels, and the dynamic elastic modulus. To simulate real conditions of the road environment in the cold area, the lowest temperature of −20°C, six freeze-thaw cycles of 0, 30, 60, 90, 120, and 150, and seven different stress levels of 0.4, 0.5, 0.6, 0.7, 0.8, and 0.9 of the compressive strength were employed in this study. The test results showed that the mass loss rate was 6%–11.2% and the compressive strength decreased by 6.51%–47% after 30–150 freeze-thaw cycles. When the stress level reached its critical value, the relative dynamic elastic modulus decreased with the number of freeze-thaw cycles. After 150 freeze-thaw cycles, failure did not appear when the stress level was lower than 50%, above which the creep failure was determined by the stress level and the number of the freeze-thaw cycles. Meanwhile, it was found that the cracking and interfacial debonding between the matrix and the crumb rubber particle were the main reasons for the degradation of CRC creep performance. Finally, a Weibull distribution-based empirical creep damage model was established to predict the failure of CRC, which can enhance its application to related engineering.


Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1260
Author(s):  
Tao Luo ◽  
Chi Zhang ◽  
Chaowei Sun ◽  
Xinchao Zheng ◽  
Yanjun Ji ◽  
...  

The reuse of rubber in concrete results in two major opposing effects: an enhancement in durability and a reduction in mechanical strength. In order to strengthen the mechanical properties of rubber concrete, steel fibers were added in this research. The compressive strength, the four-point bending strength, the mass loss rate, and the relative dynamic elastic modulus of steel fiber reinforced rubber concrete, subjected to cyclic freezing and thawing, were tested. The effects of the content of steel fibers on the freeze–thaw resistance are discussed. The microstructure damage was captured and analyzed by Industrial Computed Tomography (ICT) scanning. Results show that the addition of 2.0% steel fibers can increase the compressive strength of rubber concrete by 26.6% if there is no freeze–thaw effect, but the strengthening effect disappears when subjected to cyclic freeze–thaw. The enhancement of steel fibers on the four-point bending strength is effective under cyclic freeze–thaw. The effect of steel fibers is positive on the mass loss rate but negative on the relative dynamic elastic modulus.


2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Kyoung-Chul Kim ◽  
In-Hwan Yang ◽  
Changbin Joh

This paper describes an experimental study on the mechanical properties of high-strength fiber-reinforced concrete (HSFRC). The experimental parameters included the content and length of the steel fiber as well as the use of either a single-type fiber or hybrid steel fibers. The steel fiber contents were 1.0, 1.5, and 2.0% based on the volume of HSFRC, and the steel fiber lengths were 13, 16.5, and 19.5 mm. In addition, hybrid steel fibers incorporating steel fibers of different lengths were used. Compression tests and crack mouth opening displacement tests were performed for each HSFRC mixture with different experimental parameters. The mechanical properties of the HSFRC, such as compressive strength, elastic modulus, and tensile strength, increased with the steel fiber content. The mechanical property results of the HSFRC mixture using a single fiber length of 13 mm were greater than the results of the other mixtures. The compressive strength, elastic modulus, and tensile strength of the HSFRC mixture with hybrid steel fibers were similar to those of the mixtures with a single length of steel fiber. Additionally, based on the test results of the material properties, equations for predicting the elastic modulus and tensile strength of the HSFRC were suggested; the predictions using the proposed formula closely agreed with the experimental results.


2013 ◽  
Vol 859 ◽  
pp. 56-59 ◽  
Author(s):  
Yong Qiang Ma

A large number of experiments have been carried out in this study to reveal the effect of the steel fiber dosage on the mechanical properties of HPC (high performance concrete). The mechanical property includes compressive strength, elastic modulus and flexural strength. The results indicate that the addition of steel fiber increase the compressive strength, elastic modulus and flexural strength of HPC. When the steel fiber dosage is less than 2%, these mechanical property parameters are increasing gradually with the increase of steel fiber dosage, while these parameters begin to decrease when the steel fiber dosage is more than 2%. With the development of HPC, the application of steel fibers in HPC becomes more and more popular. In the actual construction of steel fiber reinforced HPC, the dosage of steel fiber should be controlled strictly in order to ensure that the steel fibers can perform their best improvement on high performance concrete.


Sign in / Sign up

Export Citation Format

Share Document