scholarly journals Thermal Performance of Alginate Concrete Reinforced with Basalt Fiber

Crystals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 779
Author(s):  
Seyed Esmaeil Mohammadyan-Yasouj ◽  
Hossein Abbastabar Ahangar ◽  
Narges Ahevani Oskoei ◽  
Hoofar Shokravi ◽  
Seyed Saeid Rahimian Koloor ◽  
...  

The sustainability of reinforced concrete structures is of high importance for practitioners and researchers, particularly in harsh environments and under extreme operating conditions. Buildings and tunnels are of the places that most of the fire cases take place. The use of fiber in concrete composite acts as crack arrestors to resist the development of cracks and enhance the performance of reinforced concrete structures subjected to elevated temperature. Basalt fiber is a low-carbon footprint green product obtained from the raw material of basalt which is created by the solidification of lava. It is a sustainable fiber choice for reinforcing concrete composite due to the less consumed energy in the production phase and not using chemical additives in their production. On the other hand, alginate is a natural anionic polymer acquired from cell walls of brown seaweed that can enhance the properties of composites due to its advantage as a hydrophilic gelling material. This paper investigates the thermal performance of alginate concrete reinforced with basalt fiber. For that purpose, an extensive literature review was carried out then two experimental phases for mix design and to investigate the compressive strength of samples at a temperature range of 100–180 °C were conducted. The results show that the addition of basalt fiber (BF) and/or alginate may slightly decrease the compressive strength compared to the control concrete under room temperature, but it leads to control decreasing compressive strength during exposure to a high temperature range of 100–180 °C. Moreover, it can be seen that temperature raise influences the rate of strength growth in alginate basalt fiber reinforced concrete.

Author(s):  
Janis Šliseris ◽  
Līga Gaile ◽  
Leonids Pakrastiņš ◽  
Kārlis Rocēns

The ever increasing tendency of more complex architecture and increasing use of basalt fibers in concrete, mainly due to corrosion resistance, requires a suitable, accurate and computationally efficient numerical method for modelling of mechanical behavior. A novel numerical modelling methodology for basalt fiber reinforced concrete structures is proposed. In this paper, the main focus is on modelling concrete beams with basalt longitudinal rebars and steel shear rebars. The proposed method is based on two step simulation method. On the first step a database of flexural stiffness depending on stress-strain state is created using non-linear simulations with continuum finite elements. The database of flexural stiffness is used in second step by performing nonlinear beam finite element simulation of frame structures. The numerical method showed good agreement with experimental results. The use of pre-computed database of flexural stiffness significantly accelerate non-linear simulations and whole building can analyzed by taking into account material non-linearity.


Author(s):  
Janis Šliseris ◽  
Līga Gaile ◽  
Leonids Pakrastiņš ◽  
Kārlis Rocēns

The ever increasing tendency of more complex architecture and increasing use of basalt fibers in concrete, mainly due to corrosion resistance, requires a suitable, accurate and computationally efficient numerical method for modelling of mechanical behavior. A novel numerical modelling methodology for basalt fiber reinforced concrete structures is proposed. In this paper, the main focus is on modelling concrete beams with basalt longitudinal rebars and steel shear rebars. The proposed method is based on two step simulation method. On the first step a database of flexural stiffness depending on stress-strain state is created using non-linear simulations with continuum finite elements. The database of flexural stiffness is used in second step by performing nonlinear beam finite element simulation of frame structures. The numerical method showed good agreement with experimental results. The use of pre-computed database of flexural stiffness significantly accelerate non-linear simulations and whole building can analyzed by taking into account material non-linearity. 


2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Lina Xu ◽  
Daohan Song ◽  
Ning Liu ◽  
Wei Tian

Concrete materials are an important part of global structure, and their fire resistance directly affects the safety of buildings and tunnels. In this study, basalt fiber was used to reinforce concrete with high content of stone powder in order to enhance its high-temperature performance. The mechanical properties and ultrasonic characteristics at different temperatures were studied using the cube compressive strength test and nonlinear ultrasonic test. The results indicated that the addition of basalt fiber in specimens improved their compressive strength; however, this strength did not continuously increase with increases in the fiber length and fiber content, and the optimal values for fiber length and fiber content were determined to be 12 mm and 1 kg/m3 at 600°C, respectively. With increases in temperature, the unconfined compressive strength increased first and then decreased. When the temperature was 400°C, the unconfined compressive strength of the specimens reached their highest values and then decreased. When the temperature was 400°C and 600°C, the strength of the stone powder concrete with fiber was higher than that without fiber, which shows that fiber can improve the mechanical properties of concrete at high temperatures. Based on the Box-Behnken design (BBD) method, the unconfined compressive strength response regression model of basalt fiber-reinforced concrete with high content of stone powder, which follows parameters including fiber content, fiber length, and temperature at high-temperature environments, was established, and it was found that the interaction of fiber content, fiber length, and the temperature was significant based on multifactor interaction analysis. The analysis of ultrasonic signals based on the S transform showed that, with increases in temperature, the amplitudes of the acoustic response signals, the corresponding frequency spectrum, and the time-frequency spectrum were clearly reduced. At the same temperature, the amplitudes of the acoustic response signals of different concrete testing blocks did not change much and remained at the same level.


Sign in / Sign up

Export Citation Format

Share Document