Micro-structural and mechanical properties of ultra-high performance engineered cementitious composites (UHP-ECC) incorporation of recycled fine powder (RFP)

Engineered cementitious composites (ECC) are a type of high-performance fiber reinforced cementitious composite. ECC has different applications in the construction field due to its inherent characteristics of high tensile strain. The main concern regarding ECC is its high cost. The content of cement is high contributing to its cost. In this research work, the cement in ECC is replaced with marble dust and its mechanical properties such as compressive strength and flexure strength have been assessed. For this purpose, both cubes and cylinders were tested at different test ages for finding the compressive strength development with time and observe the shape effect of specimens on the compressive strength of ECC mixes. Beam members were tested for finding the flexure strength of ECC mixes. Deflection gauge was also installed at the mid span on the bottom surface of the beams to find the maximum mid span deflection before failure. The compression test results of both cylinders and cubes revealed that using of marble dust has negative effect on the compressive strength of ECC. The flexure strength result showed that marble dust can be used up to some extent replacing cement will increase the flexure strength. The result of mid span deflection suggests that by incorporating marble dust in ECC, its ductility increases.

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Stress-Strain Properties of Engineered Cementitious Composites (ECC) Exposed to Sulfate Dry-Wet Cycle

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.858.182 ◽

2020 ◽

Vol 858 ◽

pp. 182-187

Author(s):

Yu Dong Han ◽

Zhen Bo Wang ◽

Zi Jie Hong ◽

Jian Ping Zuo ◽

Chang Liu ◽

...

Keyword(s):

High Performance ◽

Strain Softening ◽

High Performance Concrete ◽

Cementitious Composites ◽

Ultra High Performance Concrete ◽

Stress Strain ◽

Engineered Cementitious Composites ◽

Marine Concrete ◽

New Generation ◽

Satisfactory Prediction

The brittleness and easiness to crack expose marine concrete to serious durability issues. Engineered Cementitious Composites (ECC), as a new generation of ultra high performance concrete, is expected to overcome the strain-softening properties of traditional concrete and realize function of crack-width control. In this paper, the sulfate erosion of ECC under drying-wetting cycles was modelled in laboratory test. And the compression test on cylinders after exposure to different erosion cycles was implemented to obtain the stress-strain properties. The results disclose that sulfate erosion imposes significant influence on both the nonlinear ascending and descending portions of the stress-strain properties of ECC. As the erosion period extended, ECC strength undergoes an obvious increase. And the descending section of the eroded ECC shows a significant stress drop, which is quite different from that before erosion. Additionally, a simple analytical model was proposed to provide satisfactory prediction of the stress-strain properties of ECC exposed to sulfate erosion.

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Development of ultra-high performance engineered cementitious composites using polyethylene (PE) fibers

Construction and Building Materials ◽

10.1016/j.conbuildmat.2017.10.040 ◽

2018 ◽

Vol 158 ◽

pp. 217-227 ◽

Cited By ~ 126

Author(s):

Ke-Quan Yu ◽

Jiang-Tao Yu ◽

Jian-Guo Dai ◽

Zhou-Dao Lu ◽

Surendra P. Shah

Keyword(s):

High Performance ◽

Cementitious Composites ◽

Engineered Cementitious Composites

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Structural behaviors of ultra-high performance engineered cementitious composites (UHP-ECC) beams subjected to bending-experimental study

Construction and Building Materials ◽

10.1016/j.conbuildmat.2018.05.122 ◽

2018 ◽

Vol 177 ◽

pp. 102-115 ◽

Cited By ~ 37

Author(s):

Yao Ding ◽

Ke-Quan Yu ◽

Jiang-tao Yu ◽

Shi-lang Xu

Keyword(s):

Experimental Study ◽

High Performance ◽

Cementitious Composites ◽

Engineered Cementitious Composites ◽

Structural Behaviors

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Enhancing the Capillary Force of Binder-Jetting Printing Ti6Al4V and Mechanical Properties under High Temperature Sintering by Mixing Fine Powder

Metals ◽

10.3390/met10101354 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1354

Author(s):

Yang Tang ◽

Zheguan Huang ◽

Jianming Yang ◽

Yonglin Xie

Keyword(s):

Mechanical Properties ◽

Capillary Force ◽

High Performance ◽

Three Dimensional ◽

Fine Powder ◽

Green Body ◽

Mixed Powder ◽

Powder Bed ◽

Polymer Binders

Binder jet 3D printing (BJ3DP) is an additive manufacturing technology that selectively deposits binder on powder to form a three-dimensional green body followed by sintering process. The low strength of green body and metallurgical issues limit the manufacture of Ti6Al4V parts with high-performance and that are lightweight. In this study, thermal-bubble inkjet technology was used to print Ti6Al4V parts via jetting low-concentration in-situ polymer binders. In addition, a method for mixing fine powder was used to enhance the capillary force of the powder bed and mechanical properties of the parts. The results show that the capillary force was enhanced from 8.35 kPa for pure powder to 16.27 kPa for mixed powder by mixing fine powder. The compression strength of green body was enhanced from 1.5 MPa to 3.21 MPa. After sintering, the sample with mixed powder sintered at 1420 °C for 2 h had achieved a maximum density of 95.2%, microhardness of 316 HV, and yield stress of 589 MPa. The relative density of 95.2% of Ti6Al4V parts fabricated by BJ3DP technology in our study is significantly higher than the value reported in the existing literature. Finally, the porous structure with a size of 550 μm was fabricated. Results presented demonstrate that BJ3DP can produce Ti6Al4V parts with excellent properties.

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