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

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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Flexural Strength Evaluation of Reinforced Concrete Members with Ultra High Performance Concrete

Advances in Materials Science and Engineering ◽

10.1155/2016/2815247 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Baek-Il Bae ◽

Hyun-Ki Choi ◽

Chang-Sik Choi

Keyword(s):

Flexural Strength ◽

High Performance ◽

Strain Softening ◽

Steel Fiber ◽

High Performance Concrete ◽

High Strength ◽

Tension Stress ◽

Compression Stress ◽

Ultra High Performance Concrete ◽

Stress Block

Flexural strength evaluation models for steel fiber reinforced ultra high strength concrete were suggested and evaluated with test results. Suggested flexural strength models were composed of compression stress blocks and tension stress blocks. Rectangular stress block, triangular stress block, and real distribution shape of stress were used on compression side. Under tension, rectangular stress block distributed to whole area of tension side and partial area of tension side was used. The last model for tension side is realistic stress distribution. All these models were verified with test result which was carried out in this study. Test was conducted by four-point loading with 2,000 kN actuator for slender beam specimen. Additional verifications were carried out with previous researches on flexural strength of steel fiber reinforced concrete or ultra high strength concrete. Total of 21 test specimens were evaluated. As a result of comparison for flexural strength of section, neutral axis depth at ultimate state, models with triangular compression stress block, and strain-softening type tension stress block can be used as exact solution for ultra high performance concrete. For the conservative and convenient design of section, modified rectangular stress block model can be used with strain softening type tension stress block.

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Flexural Behavior of Prestressed UHPC Beams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.1145 ◽

2011 ◽

Vol 243-249 ◽

pp. 1145-1155

Author(s):

Jian Yang ◽

Zhi Fang ◽

Gong Lian Dai

Keyword(s):

High Performance ◽

High Performance Concrete ◽

Strain Curve ◽

Flexural Behavior ◽

Experimental Program ◽

Ultra High Performance Concrete ◽

Stress Strain ◽

Flexural Response ◽

Strain Relationship ◽

Relationship Of

Ultra High Performance Concrete (UHPC), which has very special properties that are remarkably different to the properties of normal and high performance concrete, is being increasingly used for the construction of structure. In this paper, an experimental program was formulated to investigate the characteristics of complete stress-strain curve of UHPC in uniaxial compression and flexural behaviors of prestressed UHPC beams. The particular focus was the influence of the partial prestress ratio and jacking stress on the flexural response of UHPC beams. The results show that UHPC is of good deformability, and a general form of the serpentine curve is proposed to represent the complete stress-strain relationship of UHPC in compression. The tests of beams demonstrated that the UHPC beams have an excellent behavior in load carrying capacity, crack distribution and deformability, their ultimate deflection can reach 1/34～1/70 of the span. Based on this investigation, theoretical correlations for the prediction structure response of UHPC beam are proposed.

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Ultra-high performance concrete – properties and technology

Bulletin of the Polish Academy of Sciences Technical Sciences ◽

10.2478/bpasts-2013-0017 ◽

2013 ◽

Vol 61 (1) ◽

pp. 183-193 ◽

Cited By ~ 11

Author(s):

T. Zdeb

Keyword(s):

Mechanical Properties ◽

Hydrothermal Treatment ◽

High Performance ◽

High Performance Concrete ◽

Qualitative Evaluation ◽

High Strength ◽

Ultra High Performance Concrete ◽

Characteristic Features ◽

Reactive Powder ◽

New Generation

Abstract The paper deals with information concerning properties and technology of a new generation cementitious composite i.e. Ultra-High Performance Concrete. High performance here means both high strength and high durability under the influence of environmental factors. This group of composites is mainly represented by Reactive Powder Concretes (RPC), which show both outstanding durability and mechanical properties. Characteristic features of RPC are mainly due to the very low water-cement ratio, which involves application of superplasticizer, significant reduction of aggregate grains size as well as hydrothermal treatment. In the first part of the paper selected properties of RPC are compared to ordinary concrete and to other groups of new generation concrete. Moreover, fundamental technological factors influencing properties of RPC are described as well. The second part deals with the RPC developed at Cracow University of Technology. The presented test results are mainly focused on the influence of steel fibres content on mechanical properties of reactive powder concrete and hydrothermal treatment on composites microstructure. The quantitative and qualitative evaluation of this relationship expand the knowledge of the UHPC technology. Finally, the third part presents the most significant and newest structures which have been erected with the use of RPC

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Review of Self-sensing Capability of Ultra-high Performance Concrete

Frontiers in Materials ◽

10.3389/fmats.2021.746022 ◽

2021 ◽

Vol 8 ◽

Author(s):

Jinkang Lian ◽

Chao Hu ◽

Tengfei Fu ◽

Yulin Wang

Keyword(s):

Carbon Nanotubes ◽

Health Monitoring ◽

High Performance ◽

High Performance Concrete ◽

Steel Fibers ◽

Ultra High Performance Concrete ◽

Structure Health Monitoring ◽

Stress Strain ◽

Electrically Conductive ◽

Conductive Materials

Ultra-high performance concrete (UHPC) has the inherent potential to self-sensing capability due to its inclusion of steel fibers or other electrically conductive materials. Many studies have investigated the electrical and piezoresistive properties of UHPC. With the incorporation of micro steel fibers, carbon nanotubes, carbon nanofibrils, or nano graphite platelets, it opens up great potential to allow UHPC to effectively sense stress, strain, and crack damage. Therefore, the UHPC-based structures can achieve the functionality of structure health monitoring (SHM). This article reviews the recent advances in self-sensing capability of various UHPC-based materials with the focus on sensing capability and mechanisms. Future applications and challenges are also discussed.

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Experimental Study of Uniaxial Tensile of High Performance Ductile Engineered Cementitious Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.255-260.2444 ◽

2011 ◽

Vol 255-260 ◽

pp. 2444-2448

Author(s):

Jia Liang Kou ◽

Ming Ke Deng ◽

Xing Wen Liang

Keyword(s):

Tensile Strength ◽

High Performance ◽

Tensile Strain ◽

Elasticity Modulus ◽

Plain Concrete ◽

Uniaxial Tensile ◽

Cementitious Composites ◽

Peak Strain ◽

Stress Strain ◽

Engineered Cementitious Composites

The tensile properties of high performance ductile engineered cementitious composites are tested through 60 specimens divided into 5 groups according to adding 5 various PVA fibres, the tensile strength, tensile elasticity modulus and the tensile pseudostrain-hardening stress-strain curves are obtained, the corresponding matrices are also tested for tension, the tensile strength relationships between different PVA fibres, and between tensile elasticity modulus and tensile strength are proposed according to the test results. In addition, multicracking can be see, and the ultimate tensile strain of partial high performance ductile engineered cementitious composites with filling different PVA fibres can reach to 3% which is 1000 times of the plain concrete. The influences of matrix and the different PVA fibres on ultimate tensile strain, peak stress and peak strain are analyzed by experimental data. At last, the tensile pseudostrain-hardening stress-strain curves are discussed, the experimental conclusions can provide a lot of experimental and theoretical bases for making the composites hold the high ductility consumption ability.

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The Stress-Strain Behavior of Densified Mix Design of Concrete

Journal of Mechanics ◽

10.1017/s1727719100004093 ◽

2002 ◽

Vol 18 (4) ◽

pp. 185-192

Author(s):

Ping-Kun Chang

Keyword(s):

High Performance ◽

Strain Softening ◽

High Performance Concrete ◽

Strain Curve ◽

Type I ◽

Peak Strain ◽

Stress Strain Curve ◽

Stress Strain ◽

Strain Behavior ◽

Slump Flow

ABSTRACTThis paper investigates the compressive strength and workability of High-Performance Concrete (HPC) which yields a slump at 250 ± 20mm and a slump flow at 650 ± 50mm. From the complete stress-strain curve, it shows the peak strain will be higher while the strength increases. Two kinds of the post failure models can be distinguished. The first type (Type I) is called strain softening and the second type (Type II) is called strain snapping back. Also, it is found that the modulus of elasticityEcdecreases as the volume of cementitious pasteVpincreases. On the other hand, Poisson's ratio ν increases asVpincreases.

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Confinement of rectangular columns made with engineered cementitious composites (ECC)

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2019-0313 ◽

2020 ◽

Vol 47 (11) ◽

pp. 1215-1225

Author(s):

Wai Man Wong ◽

Carlos A. Cruz-Noguez ◽

Mohammad J. Tolou-Kian

Keyword(s):

High Performance ◽

Compressive Load ◽

High Strength ◽

Longitudinal Direction ◽

Strength Loss ◽

Cementitious Composites ◽

Stress Strain ◽

Engineered Cementitious Composites ◽

Conventional Concrete ◽

Strain Behavior

Engineered cementitious composites (ECC) is a type of high-performance fiber-reinforced cementitious composites (HPFRCC) designed to achieve high tensile strain capacity with strain hardening effect during the post-cracking response. Previous studies show that ECC has high damage-tolerance capacity in tension, increasing the durability, safety, and sustainability of structures susceptible to cracking and spalling under moderate to severe loading. Under compression, however, there is a lack of data regarding confinement effects on steel-reinforced ECC (RECC) members. Thus, designing ECC structures is usually done by assuming the ECC behaves in the same way as conventional concrete under compression. With scarce experimental data available, this assumption may be inaccurate, uneconomical, or even unsafe. An experimental test program on confined ECC columns was performed in this study. Sixteen 100 mm × 100 mm × 300 mm ECC square columns, consisting of one set of unconfined ECC and three sets of confined ECC with 1%, 1.5%, and 2% transverse steel content were fabricated and tested under monotonic compressive load until failure. The force–displacement and stress–strain relationships in the longitudinal direction were measured. The results show that confined ECC has a compressive stress–strain behavior similar to that of confined high-strength concrete, with a rapid compressive strength loss after peak strength, and a gradual loss of strength that is inversely proportional to the amount of steel reinforcement. An empirical stress–strain model for rectangularly confined high-strength ECC was developed based on an existing model for high-strength conventional concrete.

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Compressive Strength Prediction of Green Ultra-High Performance Concrete (GUHPC) Based on Adaptive Network-Based Fuzzy Inference System

CONVERTER ◽

10.17762/converter.324 ◽

2021 ◽

pp. 587-593

Author(s):

Angran Xu

Keyword(s):

Compressive Strength ◽

High Performance ◽

Fuzzy Inference ◽

High Performance Concrete ◽

Ultra High Performance Concrete ◽

Inference System ◽

Related Data ◽

Component Material ◽

New Generation ◽

Experimental Stage

Green ultra-high performance concrete (GUHPC) is considered to be a new generation of construction materialsthat adapt to sustainable development and is gradually being used in the fields of bridge reinforcement, housefacades, and paving.To improve the efficiency of green ultra-high performance concrete in the experimental stageand to save the component material, the prediction of the 28-day compressive strength of green ultra-highperformance concrete has become a challenging task. According to the published literature, the compressivestrength of concrete is closely related to the material composition such as cement, fly ash, silica fume, sand, etc. Soin this study, 175 groups of related data of GUHPC were collected to form a database, and an artificial neuralnetwork system combined with IF-THEN fuzzy rules was utilized to establish a model that could better predict the28-day compressive strength of GUHPC. Three evaluation indicators, RMSE, R2, and MAPE, indicate that theprediction of the compressive strength of green ultra-high performance concrete made by the model is completelyreliable. Overall,this study successfully proposes a fuzzy artificial neural network model for predicting the 28-daycompressive strength of GUHPC, which provides a viable prediction tool for GUHPC in the experimental stage.

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