Column-to-beam flexural strength ratio for performance-based design of RC moment frames

The waste rubber powder application key technology in cement based materials is to solve the rubber and cement based materials interface bonding problem. NaOH, PVA and KH560 modified rubber powder is added to the rubber mortar. The test results show that, KH560 modified rubber mortar compressive strength increased by 7.4% compared to the unmodified rubber mortar; NaOH modified rubber mortar flexural strength increased by16.7% compared to the unmodified rubber mortar; Compressive and flexural strength ratio lower 37.9%. Scanning electron microscopy and infrared spectra are analyzed from the test results microscopic aspect.

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Polypropylene Fiber Reinforced Concrete for Rigid Airfield Pavement

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.228-229.627 ◽

2011 ◽

Vol 228-229 ◽

pp. 627-633

Author(s):

Tammam Merhej ◽

Liang Liang Cheng ◽

De Cheng Feng

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Volume Fraction ◽

Polypropylene Fiber ◽

Fiber Reinforced Concrete ◽

Modulus Of Rupture ◽

Polypropylene Fibers ◽

Strength Ratio ◽

Flexural Toughness ◽

Volume Fractions

The effect of adding polypropylene fibers; with different shapes and volume fractions; on the compressive strength, modulus of rupture, load-deflection curve and flexural toughness (equivalent flexural strength ratio) of concrete was investigated. Crimped and twisted polypropylene fibers were used with 0.0%, 0.2%, 0.4% and 0.6% volume fractions. It was found that the compressive strength, flexural strength and the equivalent flexural strength ratio of concrete increased about 11%, 25% and 40% respectively by adding 0.6% volume fraction of twisted polypropylene fiber. In addition; it was found that the contribution of polypropylene fiber to the flexural strength and flexural toughness was more effective when twisted polypropylene fiber was added comparing to crimped polypropylene fibers. The experimental results were used in numerical example using FAARFIELD program to explore the airfield pavement thickness reduction resulted from polypropylene fiber incorporation.

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Flexural Behavior of Compacted-Cement Sand Reinforced with Geogrid

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.856.360 ◽

2020 ◽

Vol 856 ◽

pp. 360-366

Author(s):

Uthairith Rochanavibhata ◽

Marupatch Jamnongwong ◽

Supphanut Chuenjaidee ◽

Pitthaya Jamsawang ◽

Xiao Bin Chen

Keyword(s):

Flexural Strength ◽

Performance Test ◽

Construction Material ◽

Flexural Behavior ◽

Type I ◽

Strength Ratio ◽

Pavement Materials ◽

Flexural Performance ◽

Study Type ◽

Cementing Agent

An improvement of flexural strength of cement stabilized soils using geogrid designated as compacted cement-geogrid-sand (CCGS) is investigated in this research. The studied material performance of the CCGS includes postpeak behavior, toughness, and equivalent flexural strength ratio. The geogrid inclusion significantly improves the postpeak flexural behavior, which is a requirement for bound pavement materials. The first peak flexural strength f1 and stiffness of both compacted-cement-sand (CCS) and CCGS are essentially the same for the same cement content. The tested soils were obtained from Ayutthaya province, Thailand, and is commonly used as a construction material for backfill and pavement applications. The backfill soils were used sand. In this study, Type I Portland cement was used as a cementing agent and geogrid two type were used as a reinforcement material. Properties of the cement and the geogrid, which were obtained from the manufacturers. The specimens were subjected to a flexural performance test according to ASTM C1609/C1609M-10 (2010). The results showed that in the flexural performance of the CCGS includeing postpeak behavior, toughness, and equivalent flexural strength ratio depends on the type and shape of apertures of the geogrid. It was found that the triaxial geogrid with shape of triangular apertures was more effective in reinforcing and provided the high equivalent flexural strength over uniaxial geogrid.

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Performance-based design and collapse evaluation of Buckling Restrained Knee Braced Truss Moment Frames

Engineering Structures ◽

10.1016/j.engstruct.2013.12.014 ◽

2014 ◽

Vol 60 ◽

pp. 23-31 ◽

Cited By ~ 40

Author(s):

Nattapat Wongpakdee ◽

Sutat Leelataviwat ◽

Subhash C. Goel ◽

Wen-Cheng Liao

Keyword(s):

Performance Based Design ◽

Moment Frames

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General Performance of Sulfonic Group Modified Polycarboxylate-Type Superplasticizer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.2375 ◽

2011 ◽

Vol 396-398 ◽

pp. 2375-2378

Author(s):

Yan Lin Sun ◽

Hong Wang ◽

Hui Xiang Du ◽

Yun Hua Huang

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Physical Properties ◽

Cement Paste ◽

Strength Properties ◽

Carboxyl Group ◽

Strength Ratio ◽

Sulfonic Group ◽

Group Content ◽

General Performance

The polycarboxylate-type superplasticizers (PCS) modified by sulfonic group were prepared. The influence of sulfonic group content on the performance of cement admixtures when using sulfonic group modified PCS was discussed. Some physical properties such as dispersion, cement paste fluidity, mortar fluidity, compressive strength ratio and flexural strength ratio were investigated. The results show that when using PCS with sulfonic group content 20%~25% (mol/mol of total carboxyl group), the dispersion and fluidity of concrete can be distinctly improved, meanwhile the strength properties can be maintained.

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Effect of Polypropylene Fiber on the Flexural Strength Properties of Lightweight Foam Mixed Soil

Advances in Materials Science and Engineering ◽

10.1155/2019/1607325 ◽

2019 ◽

Vol 2019 ◽

pp. 1-12

Author(s):

Raksiri Sukkarak ◽

Pornkasem Jongpradist ◽

Pitthaya Jamsawang ◽

Piti Sukontasukkul ◽

Prinya Chindaprasirt

Keyword(s):

Flexural Strength ◽

Strain Hardening ◽

Residual Strength ◽

Cement Content ◽

Polypropylene Fiber ◽

Strength Properties ◽

Flexural Properties ◽

Strength Ratio ◽

Flexural Performance ◽

Lightweight Foam

This study examines the effect of polypropylene fiber on the flexural strength properties of lightweight foam mixed soil (LFS). The flexural properties of LFS comprising different proportions of polypropylene fiber (58 mm) at different volume fractions (0.5%, 0.75%, and 1%), three different cement contents of 100, 150, and 200 kg/m3, and densities of 0.8, 1.0, and 1.2 g/cm3 were thoroughly investigated. The flexural performance of LFS according to ASTM C1609 was achieved after 28 days of aging. The results show that the flexural characteristics of LFS could be enhanced by fiber additives, as indicated by the increase in the flexural/residual strength and equivalent flexural strength ratio. The flexural performance is also related to the mixing components, including the density and cement content. For the toughness behavior, the equivalent flexural strength ratio reached up to 100%, which could be achieved with the strain-hardening specimens. The fiber inclusion is more efficient with an increase in the density and cement content of specimens as shown by the overall rating of the flexural performance.

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Experimental Study of Cement Alkali-Resistant Glass Fiber (C-ARGF) Grouting Material

Materials ◽

10.3390/ma13030605 ◽

2020 ◽

Vol 13 (3) ◽

pp. 605 ◽

Cited By ~ 3

Author(s):

Zhenyue Shi ◽

Qingbiao Wang ◽

Lei Xu

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Flexural Strength ◽

Glass Fiber ◽

High Strength ◽

Strength Ratio ◽

Karst Tunnel ◽

Grouting Material ◽

Early Strength ◽

Grouting Materials

Mixing alkali-resistant glass fiber (ARGF) into grouting slurry can prevent the development of cracks; thus, understanding the properties of ARGF grouting material is important for applications in engineering. Two types of ARGFs (Cem-FIL®60 and Anti-Crak®HD) were selected as mixing materials, and their performance was tested in four areas, namely, compressive strength, tensile strength, flexural strength, and impervious performance, under four different mixing amounts of fiber (0%, 0.25%, 0.5%, and 1.0%). Results demonstrate that the addition of ARGF increased the compressive strength and tensile strength of the grouting slurry, and the best performance was at 0.5%. The effect on the flexural strength and impervious performance was related to the mixing amount, and the fiber may have induced a counter-effect for certain amounts of added ARGF. Mixing ARGF could increase the early strength ratio of grout; however, a high early strength ratio did not necessarily result in high strength, as the flexural strength did not change synchronously with the early strength ratio; a similar pattern was found for the impermeability. Cem-FIL®60 had a better effect on the properties of grouting materials than Anti-Crak®HD. These results were successfully applied in the water-plugging and reinforcement engineering of a karst tunnel.

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