scholarly journals Optimization of the Mechanical Formulation of Typha Concrete

2021 ◽  
Vol 10 (3) ◽  
pp. 54-58
Author(s):  
Adam Gaye ◽  
Mamadou Babacar Ndiaye ◽  
Oumar Diallo ◽  
Harouna Mamadou Bal ◽  
Salif Gaye
Keyword(s):  
Energy Efficiency ◽  
Compressive Strength ◽  
Mechanical Strength ◽  
Mechanical Characteristics ◽  
Mechanical Performance ◽  
Building Sector ◽  
Load Bearing ◽  
Mechanical Formulation ◽  
Typha Australis ◽  
Great Availability

In order to address energy efficiency issues in the building sector, we conducted this study which focuses on the optimization of the mechanical characteristics of Typha concrete for its use in load-bearing structures of buildings. The fact that buildings are very energy-intensive makes it essential to develop new forms of construction based on bioclimatic architecture and the valorization of certain materials considered as waste in construction. To achieve these objectives, wehave targeted the use of Typha Australis thanks to its great availability and high thermalinsulation capacity. Thus, starting from the composition of a control concrete determined bythe DreuxGorisse formulation method with a characteristic compressive strength of 20 MPaat 28 days, Typha S1 series concretes are formulated with the substitution of sand up to 40, 50,and 60% of Typha. In order to increase the mechanical strength of Typha S1 series concretes,the cement class and G/S ratio are increased for the second S2 series.At the end of this research, the results obtained show that some of these concretes withdifferent proportions of Typha have good mechanical performance, which depends on theirstructural use.

scholarly journals Mechanical and Durability Properties of Lightweight Foamed Concrete Containing Palm Kernel Shell

2018 ◽  
Vol 7 (3.9) ◽  
pp. 65 ◽  
Author(s):  
Hanizam Awang ◽  
Adebayo Adeshina Dauda ◽  
Wenny Arminda
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Mechanical Strength ◽  
Mechanical Performance ◽  
Palm Kernel ◽  
Dry Density ◽  
Palm Kernel Shell ◽  
Durability Properties ◽  
Foamed Concrete ◽  
Strength And Durability

The research project aimed to investigate the effect of palm kernel shell (PKS) on the mechanical strength and durability of foamed concrete at the level of 10% to 60%. The samples were designed and prepared having a dry density of 1600 kg/m3with a binder to filler ratio of 1:1.2. Hardened foamed concrete samples were subjected to air cured and tested at the age of 7, 14, 28, 56 and 90 days. Mechanical performance of the PKS foamed concrete was assessed in term of its compressive strength. Durability properties namely water absorption and vacuum porosity were investigated. The result shows that the addition of PKS to lightweight foamed concrete up to 30% significantly improve the mechanical properties and the durability of the foamed concrete.  

Weldability - Behavior of Welded Reinforcement

2019 ◽  
Vol 70 (10) ◽  
pp. 3469-3472
Keyword(s):  
Mechanical Properties ◽  
Chemical Composition ◽  
Mechanical Characteristics ◽  
Mechanical Performance ◽  
Current Work ◽  
Carbon Equivalent ◽  
Work Process ◽  
Ultimate Limit

Weldability involves two aspects: welding behavior of components and safety in operation. The two aspects will be reduced to the mechanical characteristics of the elements and to the chemical composition. In the case of steel reinforcing rebar’s, it is reduces to the percentage of Cech(carbon equivalent) and to the mechanical characteristics: the yielding limit, the ultimate limit, and the elongations which after that represent the ductility class in which the re-bars is framed. The paper will present some types of steel reinforcing rebar’s with its mechanical characteristics and the welding behavior of those elements. In the current work, process-related behavior of welded reinforcement, joint local and global mechanical properties, and their correlation with behavior of normal reinforcement and also the mechanical performance resulted in this type of joints. Keywords: welding behavior, ultimate limit, reinforcing rebar’s

scholarly journals Mechanical Behavior of Hydroxyapatite-Chitosan Composite: Effect of Processing Parameters

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 213
Author(s):  
Hamid Ait Said ◽  
Hassan Noukrati ◽  
Hicham Ben Youcef ◽  
Ayoub Bayoussef ◽  
Hassane Oudadesse ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Compressive Strength ◽  
Mechanical Strength ◽  
Bone Repair ◽  
Mechanical Stability ◽  
Three Dimensional ◽  
Processing Parameters ◽  
Composite Effect ◽  
Solid Liquid ◽  
The Impact

Three-dimensional hydroxyapatite-chitosan (HA-CS) composites were formulated via solid-liquid technic and freeze-drying. The prepared composites had an apatitic nature, which was demonstrated by X-ray diffraction and Infrared spectroscopy analyses. The impact of the solid/liquid (S/L) ratio and the content and the molecular weight of the polymer on the composite mechanical strength was investigated. An increase in the S/L ratio from 0.5 to 1 resulted in an increase in the compressive strength for HA-CSL (CS low molecular weight: CSL) from 0.08 ± 0.02 to 1.95 ± 0.39 MPa and from 0.3 ± 0.06 to 2.40 ± 0.51 MPa for the HA-CSM (CS medium molecular weight: CSM). Moreover, the increase in the amount (1 to 5 wt%) and the molecular weight of the polymer increased the mechanical strength of the composite. The highest compressive strength value (up to 2.40 ± 0.51 MPa) was obtained for HA-CSM (5 wt% of CS) formulated at an S/L of 1. The dissolution tests of the HA-CS composites confirmed their cohesion and mechanical stability in an aqueous solution. Both polymer and apatite are assumed to work together, giving the synergism needed to make effective cylindrical composites, and could serve as a promising candidate for bone repair in the orthopedic field.

scholarly journals Insight into the Mechanical Performance of the UHPC Repaired Cementitious Composite System after Exposure to High Temperatures

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4095
Author(s):  
Qing Chen ◽  
Zhiyuan Zhu ◽  
Rui Ma ◽  
Zhengwu Jiang ◽  
Yao Zhang ◽  
...  
Keyword(s):  
Compressive Strength ◽  
High Temperature ◽  
High Temperatures ◽  
Bonding Strength ◽  
Composite System ◽  
Mechanical Performance ◽  
High Performance Concrete ◽  
Interfacial Structure ◽  
Cementitious Composite ◽  
Average Percentage

In this paper, the mechanical performance of an ultra-high-performance concrete (UHPC) repaired cementitious composite system, including the old matrix and the new reinforcement (UHPC), under various high temperature levels (20 °C, 100 °C, 300 °C, and 500 °C) was studied. In this system, UHPC reinforced with different contents of steel fibers and polypropylene (PP) fibers was utilized. Moreover, the physical, compressive, bonding, and flexural behaviors of the UHPC repaired system after being exposed to different high temperatures were investigated. Meanwhile, X-ray diffraction (XRD), baseline evaluation test (BET), and scanning electron microscope (SEM) tests were conducted to analyze the effect of high temperature on the microstructural changes in a UHPC repaired cementitious composite system. Results indicate that the appearance of the bonded system changed, and its mass decreased slightly. The average percentage of residual mass of the system was 99.5%, 96%, and 94–95% at 100 °C, 300 °C, and 500 °C, respectively. The residual compressive strength, bonding strength, and flexural performance improved first and then deteriorated with the increase of temperature. When the temperature reached 500 °C, the compressive strength, bonding strength, and flexural strength decreased by about 20%, 30%, and 15% for the UHPC bonded system, respectively. Under high temperature, the original components of UHPC decreased and the pore structure deteriorated. The cumulative pore volume at 500 °C could reach more than three times that at room temperature (about 20 °C). The bonding showed obvious deterioration, and the interfacial structure became looser after exposure to high temperature.

scholarly journals Preliminary Study on the Utilization of RHA as a Performance Enhancer for Rubber Mortar

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3216
Author(s):  
Jin Li ◽  
Peiyuan Chen ◽  
Haibing Cai ◽  
Ying Xu ◽  
Chunchao Li
Keyword(s):  
Compressive Strength ◽  
Mechanical Strength ◽  
Rice Husk ◽  
Rice Husk Ash ◽  
Capillary Absorption ◽  
Optimal Dosage ◽  
Positive Effects ◽  
Waste Rubber ◽  
Chloride Resistance ◽  
Preliminary Study

In this study, rice husk ash (RHA) was explored as a strength enhancer for mortars containing waste rubber. The effects of RHA on the flow, mechanical strength, chloride resistance, and capillary absorption of rubber mortar were investigated by substituting up to 20% cement with RHA. The experimental results showed that the incorporation of rubber into mortar could be safely achieved by adding RHA as a cement substitute by up to 20% without compromising the compressive strength of mortar. Moreover, the RHA also exerted positive effects on the enhancement of the chloride resistance as well as the capillary absorption of rubber mortars, for which 15% RHA was found to be the optimal dosage.

Electromagnetic Wave Absorbing and Mechanical Properties of Cement-Based Composite Panel with Different Nanomaterials

2017 ◽  
Vol 26 (1) ◽  
pp. 096369351702600
Author(s):  
Sun Yafei ◽  
Gao Peiwei ◽  
Peng Hailong ◽  
Liu Hongwei ◽  
Lu Xiaolin ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Electromagnetic Wave ◽  
Double Layer ◽  
Mechanical Performance ◽  
Interface Structure ◽  
Composite Panel ◽  
Effective Bandwidth ◽  
Composite Panels ◽  
Frequency Range ◽  
Triple Layer

This paper presents the microstructures and mechanical and absorbing properties of double and triple layer, cement-based, composite panels. The results obtained show that the frequency range in 2-18GHz had less than −10dB effective bandwidth, which correlates with 3.7and 10.8GHz in double and triple layer cement-based composite panels. Furthermore, the double layer panel's compressive strength at 7 and 28 days was 40.2 and 61.2MPa, respectively. For the triple layer panel, the strength values were 35.6MPa and 49.2MPa. The triple layer panel's electromagnetic wave (EMW) absorbing properties were superior compared to the properties of the double layer panel. However, the triple layer panel's mechanical performance was inferior to that of the double layer panel. This study proposes that carbon nanotubes can effectively improve the compressive strength and interface structure of cement-based composite panels.

scholarly journals Amorphous fiber based on the Fe-B-C molten system for bulk reinforcement of concrete

2018 ◽  
Vol 245 ◽  
pp. 03019 ◽  
Author(s):  
Artemiy Cherkashin ◽  
Yasmin Begich ◽  
Polina Sherstobitova ◽  
Oleg Tolochko
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Mechanical Characteristics ◽  
Test Material ◽  
Comparative Tests ◽  
Physical And Mechanical Characteristics

The article deals with the use of amorphous fiber of the Fe-B-C system, which was obtained by spinning the melt. Comparative tests of the samples made on the basis of the test material on the compressive strength and tensile strength of the traditional destructive method were made. The conductivity of the samples was also tested. Physical and mechanical characteristics of the material are obtained.

Structure Optimization on FEM Biomechanical Model of Bioabsorable Pure Magnesium Skin Staple

2014 ◽  
Vol 1049-1050 ◽  
pp. 511-514
Author(s):  
Yong Hua Lao ◽  
Yue Shan Huang ◽  
Wei Rong Li ◽  
Ying Jun Wang
Keyword(s):  
Stainless Steel ◽  
Mechanical Strength ◽  
316L Stainless Steel ◽  
Mechanical Performance ◽  
Structure Optimization ◽  
Biomechanical Model ◽  
Pure Magnesium ◽  
Structural Deformation ◽  
Medical Implants ◽  
Surgical Suture

Skin Stapler is an alternative instrument, which makes surgy easily and quickly and owns fine-looking effect without scars after the wound healed, to traditional surgical suture for the wound skin sewing. Magnesium recently is considered to develop medical implants because of its beneficial biocompatibility and bioabsorability. Due its less mechanical strength than traditional 316L stainless steel used in common staple, this paper try to optimize the structure of pure magnesium skin staple by FEM models and simulation as so to assure its biomechanical safty. Using ADINA software, two staples with different pre-bended shoulders and the traditional staple without shoulder are modeling to analyze its stress and plastical strain during structural deformation under load. The results, not only of pure magnesium models but also of 316L stainless steel models, showed that the shoulders optimization on staple structure has important role in its mechanical performance. The research increases the possibility of bioabsorable magnesium material application on medical skin staple.

scholarly journals Cement-Based Materials Containing Graphene Oxide and Polyvinyl Alcohol Fiber: Mechanical Properties, Durability, and Microstructure

Nanomaterials ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 638 ◽  
Author(s):  
Wenguang Jiang ◽  
Xiangguo Li ◽  
Yang Lv ◽  
Mingkai Zhou ◽  
Zhuolin Liu ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Flexural Strength ◽  
Polyvinyl Alcohol ◽  
Mechanical Strength ◽  
Mechanical Performance ◽  
Control Sample ◽  
Corrosion Condition ◽  
Cement Based Materials ◽  
Strength And Durability ◽  
Pva Fiber

The influence of graphene oxide (GO) and polyvinyl alcohol (PVA) fiber on the mechanical performance, durability, and microstructure of cement-based materials was investigated in this study. The results revealed that compared with a control sample, the mechanical strength and durability of cement-based materials were significantly improved by adding PVA fiber and GO. The compressive and flexural strength at 28 d were increased by 30.2% and 39.3%, respectively. The chloride migration coefficient at 28 d was reduced from 7.3 × 10−12 m2/s to 4.3 × 10−12 m2/s. Under a sulfate corrosion condition for 135 d, the compressive and flexural strength still showed a 13.9% and 12.3% gain, respectively. Furthermore, from the Mercury Intrusion Porosimetry (MIP) test, with the incorporation of GO, the cumulative porosity decreased from more than 0.13 cm3/g to about 0.03 cm3/g, and the proportion of large capillary pores reduced from around 80% to 30% and that of medium capillary pores increased from approximately 20% to 50%. Scanning electron microscope (SEM) images showed a significant amount of hydration products adhering to the surface of PVA fiber in the GO and PVA fiber modified sample. The addition of GO coupling with PVA fiber in cement-based materials could promote hydration of cement, refine the microstructure, and significantly improve mechanical strength and durability.

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