scholarly journals Experimental study on spalling risk of concrete with 115~120MPa subject to ISO834 Fire

2018 ◽  
Author(s):  
Yong Du ◽  
Yu Zhu ◽  
Richard Liew
Keyword(s):  
Experimental Study ◽  
High Strength Concrete ◽  
Steel Fiber ◽  
High Strength ◽  
Steel Fibers ◽  
Vapor Compression ◽  
Mixture Ratio ◽  
Strength Concrete ◽  
High Rise ◽  
Binder Ratio

High strength concrete encased columns are being developed for erecting high-rise buildings as their higher load bearing capacity and smaller cross section size than normal concrete encased column. At ambient temperature, high strength concrete is always mixed with steel fibers to improve its ductility to match the material properties of high strength steel while constructing concrete encased columns. However, for high strength concrete at elevated temperature, spalling usually can be observed due to different thermal properties of various materials mixed such as siliceous aggregate, cement, silica fume, grit and moisture. Most of previous studies present that pore vapor compression induces high strength concrete spalling and propylene fiber can prevent it from spalling. The aim of the present experimental study is to discover the minimum propylene fiber ratio to prevent spalling of 115~120MPa concrete with aggregate and steel fiber. The experimental study carried out on 17 specimens with different water-binder ratio, steel fiber ratio and monofilament propylene fiber ratio exposed to ISO834 fire. The test results that 0.15% by volume of propylene fibers can prevent 115/120MPa high strength concrete with aggregate from spalling. It is worth noting that propylene fiber mixture ratio of 0.15% is lower than that of EN 1992-1-2 proposed up to 0.22%. Lower propylene fiber mixture ratio has been soak to improve the workability of 115~120MPa high strength concrete with steel fibers.

Effects of Three Steel Fibers on the Properties of High Strength Concrete

2013 ◽  
Vol 753-755 ◽  
pp. 576-580 ◽  
Author(s):  
Hui Lian ◽  
Yun Fei Zhang ◽  
Jiang Tao Xin ◽  
Jian Hua Yang ◽  
Guo Xin Li
Keyword(s):  
High Strength Concrete ◽  
Bending Strength ◽  
Steel Fiber ◽  
Steel Wire ◽  
High Strength ◽  
Diameter Ratio ◽  
Steel Fibers ◽  
Strength Concrete ◽  
Binder Ratio ◽  
Water To Binder Ratio

Portland cement, crushed stone, sand and superplasticizer were used to obtain a high strength concrete with a low water to binder ratio. Three steel fibers such as waste steel wire, corrugated steel fiber and arch steel fiber were added into the high strength concrete. The effects of the three fibers on the slump and the strengths such as compressive strength, tensile strength and bending strength were researched. The reduction of the slump and the increasing of the strength of the concrete with the arch steel fiber were the most significant due to the highest length-diameter ratio.

Compressive Strength and Splitting Tensile Strength of Steel Fiber Reinforced Ultra High Strength Concrete (SFRC)

2010 ◽  
Vol 34-35 ◽  
pp. 1441-1444 ◽  
Author(s):  
Ju Zhang ◽  
Chang Wang Yan ◽  
Jin Qing Jia
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
High Strength Concrete ◽  
Steel Fiber ◽  
Volume Fraction ◽  
High Strength ◽  
Splitting Tensile Strength ◽  
Steel Fibers ◽  
Fiber Reinforced ◽  
Strength Concrete

This paper investigates the compressive strength and splitting tensile strength of ultra high strength concrete containing steel fiber. The steel fibers were added at the volume fractions of 0%, 0.5%, 0.75%, 1.0% and 1.5%. The compressive strength of the steel fiber reinforced ultra high strength concrete (SFRC) reached a maximum at 0.75% volume fraction, being a 15.5% improvement over the UHSC. The splitting tensile strength of the SFRC improved with increasing the volume fraction, achieving 91.9% improvements at 1.5% volume fraction. Strength models were established to predict the compressive and splitting tensile strengths of the SFRC. The models give predictions matching the measurements. Conclusions can be drawn that the marked brittleness with low tensile strength and strain capacities of ultra high strength concrete (UHSC) can be overcome by the addition of steel fibers.

An experimental study of steel fiber-reinforced high-strength concrete slender columns under cyclic loading

2013 ◽  
Vol 57 ◽  
pp. 565-577 ◽  
Author(s):  
Karen E. Caballero-Morrison ◽  
J.L. Bonet ◽  
Juan Navarro-Gregori ◽  
Pedro Serna-Ros
Keyword(s):  
Experimental Study ◽  
Cyclic Loading ◽  
High Strength Concrete ◽  
Steel Fiber ◽  
High Strength ◽  
Fiber Reinforced ◽  
Strength Concrete ◽  
Slender Columns

scholarly journals Vitality of Steel and Polypropylene Fibers in High Strength Concrete

2019 ◽  
Vol 8 (12) ◽  
pp. 4673-4676
Keyword(s):  
Thermal Insulation ◽  
High Strength Concrete ◽  
Steel Fiber ◽  
Gradual Increase ◽  
High Strength ◽  
Fiber Content ◽  
Steel Fibers ◽  
Polypropylene Fibers ◽  
Strength Concrete ◽  
Concrete Mix

The main aim of this work was to investigate the influence of widely used steel fibers and polypropylene fibers on the concrete. From many studies it has been shown that, addition of fibers to the concrete has influenced the cracking of concrete, due to shrinkage, thermal insulation and bleeding of water. So, in this study we made use of ultra high strength concrete mix of M50, and we made use of both steel as well as polypropylene fibers to enhance the properties of the concrete. In this study total five concrete mixes were made with steel fiber in dosages of 2.5%, 2%, 1.5%, 1% and polypropylene fibers are in dosage 0%, 0.5%, 1%, 1.5% of the weight of concrete mix. The specimens were casted and all the specimens are tested for 7days and 28 days strength. The results have depicted a gradual increase in the strength of the concrete as the fiber content increased

Research on the Mixture Ratio Design of Ultra-High Strength Concrete

2013 ◽  
Vol 405-408 ◽  
pp. 2782-2788
Author(s):  
Li Bin Xu ◽  
Nai Qian Feng ◽  
Kia Hui Tew
Keyword(s):  
High Strength Concrete ◽  
Coarse Aggregate ◽  
High Strength ◽  
Mineral Admixtures ◽  
Relevant Parameter ◽  
Concrete Technology ◽  
Mixture Ratio ◽  
Strength Concrete ◽  
Binder Ratio ◽  
Water Binder Ratio

Ultra-high strength concrete (including the coarse aggregate of over 5mm), with high compressive strength and strong durability, is regarded as a new-type building material that could economize on raw materials, land and energy and the development trend of concrete technology both at home and abroad. However, the large consumption of binding materials, low water-binder ratio and the viscous mixture are prone to give rise to the inferior pumping capacity, pipe blockage and pipe break, thus preventing its massive application in the real projects. Therefore, through the design of reasonable mixture ratio, this paper makes up and produces the pumping ultra-high strength concrete of over 100MPa that contains coarse aggregate by adopting the compound design of mineral admixtures, such as slag powder, fly ash and ganister sand so as to optimize the relevant parameter of the mixture ratio. Finally it comes to the conclusion that while making up the ultra-high strength concrete of over 100MPa, it is much more reasonable to appropriately add the mixing amount of the mineral admixtures, increase the water-cement ratio and decrease the water-binder ratio.

scholarly journals PERFORMANCE OF HIGH STRENGTH CONCRETE COLUMNS REINFORCED WITH HYBRID STEEL FIBER UNDER DIFFERENT LOADING CONDITIONS

2016 ◽  
Vol 3 (1) ◽  
Author(s):  
Emdad K.Z. Balanji ◽  
M. Neaz Sheikh ◽  
Muhammad N.S. Hadi
Keyword(s):  
High Strength Concrete ◽  
Steel Fiber ◽  
Reference Group ◽  
High Strength ◽  
Concrete Columns ◽  
Steel Fibers ◽  
Loading Conditions ◽  
Strength Concrete ◽  
High Strength Concrete Columns ◽  
Strength And Ductility

The strength and ductility of high strength concrete columns improve with the addition of steel fiber. This paper reports the behavior of circular High Strength Concrete (HSC) columns reinforced with Hybrid Steel Fibers (HSF) under different loading conditions. In this study, HSF consisted of a combination of macro steel fibers and micro steel fibers. A total of eight circular specimens of 205 mm diameter and 800 mm height were cast and tested. All specimens were reinforced with same amount of steel reinforcements. The specimens were divided into two groups of four specimens. Group RC (reference group) contained no steel fibers. Group HSF (hybrid steel fibers) contained 2.5% by volume of HSF. From each group one specimen was tested under concentric loading, one under 25 mm eccentric loading, one under 50 mm eccentric loading, and one under four-point loading. The results showed that the specimens reinforced with HSF achieved higher strength and ductility compared to RC specimens under different loading conditions. It was also observed that the presence of HSF delayed the spalling of the concrete cover.

Experimental Study on the Max Crack Width of Steel Fiber Reinforced High-Strength Concrete Beams

2016 ◽  
Vol 851 ◽  
pp. 798-802
Author(s):  
Qiao Yan Guan ◽  
Juan Wang ◽  
Ming En Zhang
Keyword(s):  
Experimental Study ◽  
High Strength Concrete ◽  
Crack Width ◽  
Steel Fiber ◽  
Concrete Beams ◽  
Volume Fraction ◽  
High Strength ◽  
Fiber Reinforced ◽  
Strength Concrete ◽  
Maximum Crack

The effect of volume fraction of steel fiber and the strength of reinforcement on the maximum crack width of steel fiber reinforced high-strength concrete beams was analyzed based on experimental results. In addition, the formula to calculate the maximum crack width of steel fiber-reinforced high-strength concrete beams was established.

Sign in / Sign up

Export Citation Format

Share Document