scholarly journals DRYING SHRINKAGE AND CRACK WIDTH OF ENGINEERED CEMENTITIOUS COMPOSITES (ECC)

2003 ◽  
pp. 37-46 ◽  
Author(s):  
Martin B. WEIMANN ◽  
Victor C. LI
Keyword(s):  
Crack Width ◽  
Drying Shrinkage ◽  
Cementitious Composites ◽  
Engineered Cementitious Composites

Effects of Gradation of Sand on the Mechanical Properties of Engineered Cementitious Composites

2011 ◽  
Vol 250-253 ◽  
pp. 374-378
Author(s):  
Ying Zi Yang ◽  
Yan Yao ◽  
Yu Zhu
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Peak Load ◽  
Drying Shrinkage ◽  
Bending Test ◽  
Cementitious Composites ◽  
Paper Test ◽  
Engineered Cementitious Composites ◽  
Load Peak ◽  
Fineness Modulus

Four-point bending test was employed to investigate the effects of gradation of sand on the mechanical properties of Engineered Cementitious Composites (ECC). The characteristics of ECC such as mid-span deflection, first cracking load, peak load and fracture toughness were obtained from the load-deflection curve. Effects of gradation of sand on fresh properties, compressive strength, flexural strength and drying shrinkage of ECC were also discussed in this paper. Test results shown that when the fineness modulus of sand in ECC was 1.0, the mid-span deflection and fracture toughness of ECC increased nearly 1.5 times and 2 times that of ECC with the sand fineness modulus of 2.97, respectively. With the sand getting finer, the more superplascitizer is needed and the crack width of ECC becomes smaller. The drying shrinkage of ECC with 2.97 and 1.0 fineness modulus of sand at 24 days was 8×10-4 and 15.6×10-4, respectively.

A Review on the Methods of Improving Fiber Distribution of Engineered Cementitious Composites (ECC)

2013 ◽  
Vol 683 ◽  
pp. 46-50
Author(s):  
Heng Mao Niu ◽  
Yong Ming Xing ◽  
Yan Ru Zhao
Keyword(s):  
Surface Morphology ◽  
Strain Hardening ◽  
Crack Width ◽  
Mineral Admixtures ◽  
Cementitious Composites ◽  
Fiber Distribution ◽  
Crack Bridging ◽  
Engineered Cementitious Composites ◽  
C Fiber ◽  
Matrix Components

Engineered cementitious composites(ECC) are characterized by strain hardening and tight crack width control. Good fiber distribution can maximize fiber contribution at each stage of the crack bridging process. However, poor fiber distribution can be disadvantage to fiber contribution, even influence the robustness of strain-hardening. Combined with the latest research results, this review highlights the methods of improving fiber distribution in ECC. Good fiber distribution is based on excellent matrix fluidity, which can be determined by mineral admixtures, admixture and water/binder (w/c). Fiber included surface morphology, size and content of fiber have also an effect on fiber distribution in the ECC. Additionally, slag and sand size shape of matrix components play a surprising role on fiber distribution. Based on the reviewed methods it is argued that fiber optimization and matrix components tailoring can be used to improve fiber distribution.

Shrinkage Characteristics of Green Engineered Cementitious Composites with Varying Palm Oil Fuel Ash Contents and Water-Binder Ratios

2012 ◽  
Vol 626 ◽  
pp. 245-249 ◽  
Author(s):  
Nurdeen M. Altwair ◽  
M.A. Megat Johari ◽  
Syed Fuad Saiyid Hashim
Keyword(s):  
Palm Oil ◽  
Drying Shrinkage ◽  
Shrinkage Strain ◽  
Extensive Study ◽  
Cementitious Composites ◽  
Engineered Cementitious Composites ◽  
Palm Oil Fuel Ash ◽  
Fuel Ash ◽  
The Matrix ◽  
Oil Fuel

The present paper is a part of an extensive study on green palm oil fuel ash engineered cementitious composites conducted at Universiti Sains Malaysia. It specifically investigates the effects of waterbinder ratio (w/b) and palm oil fuel ash (POFA) on the drying shrinkage of engineered cementitious composites (ECCs). W/b values of 0.33, 0.36, and 0.38 were selected. ECC mixes were proportioned to have various ratios of POFA ranging from 0 to 1.2 from the mass of cement. The drying shrinkage measurements were taken at 4, 11, 18, 25, 57, and 90 days. The experimental results show that w/b has a significant effect on the drying shrinkage of the ECC mixtures. Drying shrinkage is remarkably reduced with a decrease in the w/b. The results also showed that drying shrinkage of the composites is considerably reduced when POFA is used in the matrix. The measured drying shrinkage strain at 90 days is only 920×10-6 µε to 1216×10-6 µε for ECC mixtures with high POFA content. The shrinkage strain of the ECC mixtures without POFA at 90 days is nearly 1597×10-6 µε to 1910×10-6 µε.

Effects of Processing on Fiber Distribution and Mechanical Performance of Engineered Cementitious Composites (ECC)

2013 ◽  
Vol 709 ◽  
pp. 122-126
Author(s):  
Heng Mao Niu ◽  
Yong Ming Xing ◽  
Yan Ru Zhao
Keyword(s):  
Strain Hardening ◽  
Crack Width ◽  
Mechanical Performance ◽  
Processing Technique ◽  
Cementitious Composites ◽  
Fiber Distribution ◽  
Engineered Cementitious Composites ◽  
Research Results

Engineered cementitious composites (ECC) are characterized by strain hardening and tight crack width control. Good fiber distribution can maximize fiber contribution. Processing can substantially influence fiber distribution, and consequently influence mechanical performance. Combined with the latest research results, this review summarizes the results of several studies in which the influence of processing on fiber distribution and mechanical performance was investigated. Based on the reviewed methods it is argued that the processing technique of producing ECC can improve fiber distribution.

scholarly journals Properties of Rubberized Engineered Cementitious Composites Containing Nano-Silica

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3765
Author(s):  
Rubendran Loganathan ◽  
Bashar S. Mohammed
Keyword(s):  
Tensile Strength ◽  
Elastic Modulus ◽  
Flexural Strength ◽  
Drying Shrinkage ◽  
Poisson's Ratio ◽  
Cementitious Composites ◽  
Nano Silica ◽  
Engineered Cementitious Composites ◽  
Direct Tensile ◽  
Direct Tensile Strength

To avoid explosive spalling during elevated temperature, crumb rubber (CR) is being added to the manufacturing of engineered cementitious composites (ECC). However, the addition of CR particles adversely affects the mechanical properties of ECC. Therefore, to overcome this issue, nano-silica (NS) is added into rubberized ECC mixture as cementitious material additives. Response surface methodology (RSM) has been utilized to optimize the mixtures of the rubberized ECC with variables: CR (0, 2.5, and 5 vol.%), polyvinyl alcohol (PVA) fiber (0, 1, and 2 vol.%), NS (0, 1, and 2 vol.%), and fly ash (0, 25, and 50 vol.%). The experimentally measured responses are flexural strength, direct tensile strength, elastic modulus, Poisson’s ratio, creep, and drying shrinkage. Mathematical models to predict the targeted responses have been developed using RSM. As a result, a high correlation between the factors and responses has been exhibited by the developed models and the accuracy of fit, where less than 9.38% of the variation was found between the predicted and validated results. The experimental results revealed that the rubberized ECC with the incorporation of nano-silica exhibited a higher compressive strength, direct tensile strength, flexural strength, elastic modulus, Poisson’s ratio, and lower drying shrinkage.

scholarly journals Investigation of Flexural Behavior of Engineered Cementitious Composites

2018 ◽  
Vol 7 (1) ◽  
pp. 84-87
Author(s):  
V. Selvapriya .
Keyword(s):  
Construction Industry ◽  
Drying Shrinkage ◽  
Fiber Reinforced Concrete ◽  
Flexural Behavior ◽  
Cementitious Composites ◽  
Volume Changes ◽  
Engineered Cementitious Composites ◽  
New Class ◽  
Micro Cracks ◽  
New Material

Traditional concrete is brittle, rigid and less durable. The search for the new material in construction industry results in the development of new class of Fiber Reinforced Concrete (FRC), known as Engineered Cementitious Composites (ECC). They impart ductility and durability to the structure. In concrete structural cracks develop even before loading, particularly due to drying shrinkage or other causes of volume changes. When loaded, the micro cracks propagate and open up, and owing to the effect of stress concentration, additional cracks form in places of minor defects. The development of micro cracks is the main cause of inelastic deformation in concrete. This paper deals with flexural behavior of ECC.

scholarly journals Influences of Sodium Lignosulfonate and High-Volume Fly Ash on Setting Time and Hardened State Properties of Engineered Cementitious Composites

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4779
Author(s):  
Anggun Tri Atmajayanti ◽  
Chung-Chan Hung ◽  
Terry Y. P. Yuen ◽  
Run-Chan Shih
Keyword(s):  
Fly Ash ◽  
Setting Time ◽  
Autogenous Shrinkage ◽  
Drying Shrinkage ◽  
High Volume ◽  
Cementitious Composites ◽  
Sodium Lignosulfonate ◽  
Engineered Cementitious Composites ◽  
Cracking Behavior ◽  
Setting Times

Engineered Cementitious Composites (ECC) exhibit high ductility accompanied by multiple narrow cracking behavior under uniaxial tension. The study experimentally investigated the influence of sodium lignosulfonate and high volumes of fly ash (HVFA) on the properties of fresh and hardened ECC, with the experimental variables including the amounts of fly ash, polyvinyl alcohol (PVA) fibers, and sodium lignosulfonate. The test results were discussed extensively in terms of the initial and final setting times, compressive and tensile behavior, and drying and autogenous shrinkage. The results indicated that the initial and final setting times of ECC were increased along with the sodium lignosulfonate content of up to 1%. The drying shrinkage development was governed by the first 14 days. In addition, the major autogenous shrinkage developed for more than 28 days. The amounts of fly ash, PVA fibers, and sodium lignosulfonate considerably impacted the autogenous shrinkage. Moreover, it was found that the dosage of sodium lignosulfonate at 0.5% of the weight of Portland cement optimally reduced the shrinkage and enhanced the tensile strain capacity for ECC.

scholarly journals A Study of Engineered Cementitious Composites by Investigating its Compressive and Flexural Strength

2021 ◽  
Author(s):  
SONA ROSE BINS ◽  
CENYA S KUMAR ◽  
Shivani Ittuveetil ◽  
SONA TOGI ◽  
MAREENA GEORGE
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Crack Width ◽  
Critical Issue ◽  
Cementitious Composites ◽  
Engineered Cementitious Composites ◽  
Unique Type ◽  
Negative Effect ◽  
Ductile Behavior

Abstract Concrete has become an essential material as a part of construction field. Its behavior is weak in tension and strong in compression. The demand for tensile strength is high for concrete because higher loading requires more than 10% of compressive strength which make a critical issue for engineers. Another major issue faced by normal concrete is lack in ductility and strain capacity. Engineered Cementitious Composites (ECC), also known as Bendable Concrete, has been designed to overcome the brittleness of concrete. It has tensile ductility of 3–5% and its self-controlled tight crack width is less than 100µm.It is a unique type of cement mixture with composition of low volume fibers (~ 2%) so as to impart ductility, ability to repair and high tensile strength besides. It also has low maintenance and is environment friendly in nature.The ECC composition does not contain coarse aggregate because they develop larger crack width which tend to have a negative effect on ductile behavior of ECC. This paper demonstrated a detailed review on properties of ECC and experimentally identified the best ECC mix by analysing the compressive the flexural strength at different ratios: 0.5%, 1%, 1.5%, 2% and 2.5% of PVA fibre. Fifteen cubes (150mm x 150mm x 150mm) were casted for compressive strength test and fifteen beams (500mm x 100mm x 100mm) were casted for flexural strength and tested at the age of 28 days. Workability test have been conducted to access the fresh properties and consistency of the concrete.

scholarly journals Interface Characterization Between Polyethylene/ Silica in Engineered Cementitious Composites by Molecular Dynamics Simulation

Molecules ◽  
2019 ◽  
Vol 24 (8) ◽  
pp. 1497 ◽  
Author(s):  
Zhou ◽  
Vu-Bac ◽  
Arash ◽  
Zhu ◽  
Zhuang
Keyword(s):  
Molecular Dynamics ◽  
Crack Width ◽  
Interfacial Adhesion ◽  
Silica Surface ◽  
Failure Process ◽  
Dynamics Simulation ◽  
Coupling Agents ◽  
Cementitious Composites ◽  
Engineered Cementitious Composites ◽  
Adhesion Properties

Polyethylene is widely adopted in engineered cementitious composites to control the crack width. A clearer knowledge of the PE/concrete interfacial properties is important in developing engineered cementitious composites, which can lead to a limited crack width. Tensile failure and adhesion properties of the amorphous polyethylene/silica (PE/S) interface are investigated by molecular dynamics to interpret the PE/concrete interface. The influence of the PE chain length, the PE chain number and coupling agents applied on silica surface on the interfacial adhesion is studied. An increase of the adhesion strength of the modified silica surface by coupling agents compared with the unmodified silica is found. The failure process, density profile and potential energy evolutions of the PE/S interface are studied. The thermodynamic work of adhesion that quantifies the interfacial adhesion of the PE/S interface is evaluated. The present study helps to understand the interfacial adhesion behavior between ECC and PE, and is expected to contribute to restricting the crack width.

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