Strengthening of RC Structures by Using Engineered Cementitious Composites: A Review

This paper presents a review of the recent work assessing the performance of building structures strengthened with engineered cementitious composite (ECC). ECC characterizes tensile strain hardening and multiple cracking properties, as well as strong interfacial bonding performance with substrate concrete, which makes it a promising retrofitting material. A lot of researches have been conducted on reinforced concrete (RC) structures, including beams, columns, beam–column joints, and fire-damaged slabs, strengthened with ECC material, and an extensive collection of valuable conclusions were obtained. These strengthening systems usually combine ECC with FRP textiles or steel bars to form a composite strengthening layer. The review demonstrates that ECC strengthening can greatly improve the performance of RC structures.

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Pull-Out Tests of Deformed Bars from Ferrous Mill Tailing Concrete

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.477-478.697 ◽

2013 ◽

Vol 477-478 ◽

pp. 697-700

Author(s):

Yan Zheng ◽

Hong Zhen Kang ◽

Guang Qi Wang

Keyword(s):

Technical Support ◽

Building Structures ◽

Structural Concrete ◽

Bond Behavior ◽

Ordinary Concrete ◽

Bonding Performance ◽

Pull Out ◽

Steel Bars ◽

Mill Tailing

For application of FMT (ferrous mill tailing) to structural concrete, it is urgent need to study the bond behavior of reinforced bars with FMT concrete. In this paper, 72 pull-out tests of HRB335 steel bars from FMT concrete were carried out. The test phenomena and various factors influence on bond behavior were obtained. The results show that the bonding performance between deformed bars and FMT concrete is approximate to that of deformed bars and ordinary concrete. The results should provide technical support for application of FMT concrete in building structures.

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Tensile Properties of Low Shrinkage Engineered Cementitious Composite

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.405-406.55 ◽

2009 ◽

Vol 405-406 ◽

pp. 55-61

Author(s):

Jun Zhang ◽

Cheng Xu Gong

Keyword(s):

Tensile Properties ◽

Drying Shrinkage ◽

Shrinkage Strain ◽

Cementitious Material ◽

Cementitious Composite ◽

Multiple Cracking ◽

Engineered Cementitious Composite ◽

New Class ◽

Cracking Characteristics ◽

Tensile Strain Capacity

This paper reports the tensile properties of a new class of engineered cementitious composite with characteristic of low drying shrinkage. Experimental results show that drying shrinkage of the composite is greatly reduced as using the low shrinkage cementitious material in matrix, while the composite remains strain-hardening and multiple cracking characteristics. The measured drying shrinkage strain at 28 days is only 10910-6 to 24210-6 for low shrinkage ECCs. For traditional ECC, the shrinkage strain at 28 days is nearly 120010-6. The average tensile strain capacity after 28 days curing is 2.5% of the low shrinkage ECC with tensile strength of 4-5MPa.

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Tensile Strain-Hardening Behavior of Polyvinyl Alcohol Engineered Cementitious Composite (PVA-ECC)

ACI Materials Journal ◽

10.14359/10851 ◽

2001 ◽

Vol 98 (6) ◽

Cited By ~ 24

Keyword(s):

Polyvinyl Alcohol ◽

Strain Hardening ◽

Tensile Strain ◽

Cementitious Composite ◽

Engineered Cementitious Composite ◽

Hardening Behavior ◽

Strain Hardening Behavior

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MECHANICAL PROPERTIES OF A PVA FIBER REINFORCED ENGINEERED CEMENTITIOUS COMPOSITE

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2014.40 ◽

2014 ◽

Vol 1 (1) ◽

Cited By ~ 1

Author(s):

Ting Huang ◽

Y.X. Zhang

Keyword(s):

Grain Size ◽

Strain Hardening ◽

Tensile Strain ◽

Construction Materials ◽

Cementitious Composite ◽

Fiber Reinforced ◽

Engineered Cementitious Composite ◽

Hardening Behavior ◽

Dog Bone ◽

Strain Hardening Behavior

High Performance Fiber Reinforced Cementitious Composites (HPFRCCs) are promising construction materials characterized by tensile strain hardening behavior. Engineered Cementitious Composite (ECC) is a special type of HPFRCC developed with enhanced ductility and durability. Coarse aggregates are usually excluded from the ECC matrix, and the reported ECCs are typically produced with microsilica sand having a maximum grain size of 200 µm. In this paper, a PVA-ECC mixture containing local dune sand with a maximum grain size of 300 µm was developed, and its compressive and tensile properties were experimentally investigated. A dog-bone-shaped specimen and a rectangular-coupon-shaped specimen were both used in the tensile test, and it was found after extensive research that the dog-bone specimen was more suitable than the rectangular coupon specimen. The experimental results from the dog-bone specimens indicated that the newly-developed composite possessed good tensile strain-hardening behavior, with a high ultimate tensile strength, and the compressive strength was comparable to that of existing PVA-ECCs.

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Mechanical behavior of a novel precast beam-to-column connection with U-shaped bars and engineered cementitious composites

Advances in Structural Engineering ◽

10.1177/1369433218761139 ◽

2018 ◽

Vol 21 (13) ◽

pp. 1963-1976 ◽

Cited By ~ 5

Author(s):

Bingqing Dong ◽

Cong Lu ◽

Jinlong Pan ◽

Qifeng Shan ◽

Wanyun Yin

Keyword(s):

Energy Dissipation ◽

Experimental Program ◽

Cementitious Composites ◽

Cementitious Composite ◽

Engineered Cementitious Composites ◽

Seismic Region ◽

Engineered Cementitious Composite ◽

Flexural Failure ◽

Bonding Performance ◽

Precast Column

This article investigates a novel precast connection, with U-shaped bars extending from precast column to connect with the longitudinal bars in precast beams. To improve the seismic behavior of the connection, engineered cementitious composites, one kind of highly ductile concrete, were introduced into the core area of the connection, which also act as the cast-in-place material in the beam top and end. Prior to the test, finite element modeling was conducted to determine the proper splice length between U-shaped bars and beam reinforcements and also to evaluate the bonding performance of the proposed connection. The experimental program was then carried out on a monolithic connection, a precast connection with normal concrete as well as a precast connection with engineered cementitious composite, after which the seismic behaviors of the connections including their failure mode, hysteresis characteristic, stiffness degradation, ductility, and energy dissipation were analyzed. All three types of connections underwent typical flexural failure where the joint area remained intact. The negative carrying capacity, ductility, and energy dissipation were slightly lower for the connection with concrete, while the connection with engineered cementitious composite exhibited satisfactory behavior comparable to monolithic specimens. The latter connection with engineered cementitious composite is therefore suggested to be applied in highly seismic region.

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