Bearing capacity of reactive powder concrete reinforced by steel fibers

According to the theory of dense packing of particle, the theoretical particle size distribution of raw materials of RPC (Reactive Powder Concrete) was calculated. On the basis, the ratio of raw materials with different range of particle sizes of the RPC was determined by mechanical experiments. According to the determined ratio, a new type RPC was prepared by using flying ash and slag to replace part of cements and quartz flour, respectively. The workability, mechanical properties of the new RPC with different mix proportion and its shrinkage, cured at the normal temperature and 60°C, respectively, were studied. The results show that when water-binder ratio is 0.23, fly ash replaces 30% cements, slag replaces 50% quartz flour and superfine steel fibers percentage in volume is 2%, the compressive and flexural strength of prepared RPC are 160.1MPa and 25.3MPa, respectively, and after 3days heat curing (60°C), the dry shrinkage of it in 28days age reaches 299um/m. In addition, the fluidity of the new RPC is 258mm and meets requirements of workability of the pump concrete.

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Investigation of the Match Relation between Steel Fiber and High-Strength Concrete Matrix in Reactive Powder Concrete

Materials ◽

10.3390/ma12111751 ◽

2019 ◽

Vol 12 (11) ◽

pp. 1751 ◽

Cited By ~ 3

Author(s):

Guangyao Yang ◽

Jiangxiong Wei ◽

Qijun Yu ◽

Haoliang Huang ◽

Fangxian Li

Keyword(s):

Compressive Strength ◽

Steel Fiber ◽

High Strength ◽

Steel Fibers ◽

Peak Strength ◽

Reactive Powder Concrete ◽

Medium Length ◽

Reactive Powder ◽

Concrete Matrix ◽

Strength And Toughness

This study investigated the strength and toughness of reactive powder concrete (RPC) made with various steel fiber lengths and concrete strengths. The results indicated that among RPC samples with strength of 150 MPa, RPC reinforced with long steel fibers had the highest compressive strength, peak strength, and toughness. Among the RPC samples with strength of 270 MPa, RPC reinforced with short steel fibers had the highest compressive strength, and peak strength, while RPC reinforced with medium-length steel fibers had the highest toughness. As a result of the higher bond adhesion between fibers and ultra-high-strength RPC matrix, long steel fibers were more effective for the reinforcement of RPC with strength of 150 MPa, while short steel fibers were more effective for the reinforcement of RPC with strength of 270 MPa.

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Bending Resistance and Failure Type Evaluation of Basalt Fiber RPC Beam Affected by Notch and Interfacial Damage Using Acoustic Emission

Applied Sciences ◽

10.3390/app10031138 ◽

2020 ◽

Vol 10 (3) ◽

pp. 1138 ◽

Cited By ~ 2

Author(s):

Hanbing Liu ◽

Xiang Lyu ◽

Yuwei Zhang ◽

Guobao Luo ◽

Wenjun Li

Keyword(s):

Acoustic Emission ◽

Basalt Fiber ◽

Steel Fibers ◽

Bending Test ◽

Reactive Powder Concrete ◽

Basalt Fibers ◽

Interfacial Damage ◽

Failure Type ◽

Bending Resistance ◽

Reactive Powder

Generally, reactive powder concrete (RPC) contains steel fibers often exposed to aggressive environments. Steel fibers in such RPCs are subjected to corrosion in-service, which can significantly change the mechanical properties of the structural components. In this paper, basalt fibers were used to replace steel fibers for preparing a new basalt fiber modified reactive powder concrete (BFRPC). The bending resistance of BFRPC beams was studied, and the crack propagation and failure type of BFRPC beam were monitored by acoustic emission (AE). During the bending test, the failure type of BFRPC was evaluated by AE. Besides, the effects of notch and interfacial damage on the bending resistance and failure type were also studied. During the test, ordinary Reactive Powder Concrete (RPC) without basalt fibers was used as a reference. Results revealed that failure type of the RPC beam and BFRPC beam was mainly caused by shear failure. The notch increased the number of tensile cracks in the beam failure crack, resulting in a decrease in the bending resistance of RPC beam and BFRPC beam. Besides, basalt fiber could improve the toughness and bending resistance of BFRPC beam and increase resistance of the BFRPC beam to notch and interface damage.

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Flexural behavior of sustainable reactive powder concrete bubbled slab flooring elements

Challenge Journal of Structural Mechanics ◽

10.20528/cjsmec.2017.04.010 ◽

2017 ◽

Vol 3 (2) ◽

pp. 81 ◽

Cited By ~ 1

Author(s):

Ashraf Abdulhadi Alfeehan ◽

Hassan Issa Abdulkareem ◽

Shahad Hameed Mutashar

Keyword(s):

Reinforced Concrete ◽

Ultimate Load ◽

Steel Fibers ◽

Flexural Behavior ◽

Reactive Powder Concrete ◽

Concrete Slabs ◽

Concrete Floor ◽

Reinforced Concrete Slabs ◽

Reactive Powder ◽

Floor System

Voided slabs are reinforced concrete slabs in which voids allow to reduce the amount of concrete. The bubbled deck slab is a new and sustainable biaxial floor system to be used as a self-supporting concrete floor. The use of voided slabs leads to decrease the consumption of materials and improve the insulation properties for enhancing the objectives of sustainability. This study presents an investigation into the flexural behavior of sustainable Reactive Powder Concrete RPC bubbled slab flooring elements. Six one-way slabs were cast and tested up to the failure. The adopted variables in this study are: the volumetric ratio of steel fibers, type of slab; bubbled or solid, placing of reinforcement and thickness of slab. The effect of each variable on the ultimate load, deflection and strain has been discussed. The results show that increasing the percent of steel fibers from 1% to 2% in solid and bubbled slabs decreases the deflection by (18.75%) and (50%) respectively. As well as, the deflection increases by (41%) for bubbled slab compared to the solid slab. The slabs reinforced with top and bottom steel meshes show less deflection than slabs reinforced by only bottom steel mesh.

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Experimental comparative study of reactive powder concrete: mechanical properties and the effective factors

MATEC Web of Conferences ◽

10.1051/matecconf/201816204004 ◽

2018 ◽

Vol 162 ◽

pp. 04004 ◽

Cited By ~ 2

Author(s):

Eyad Kadhem ◽

Ammar Ali ◽

Sameh Tobeia

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Modulus Of Elasticity ◽

High Performance ◽

High Performance Concrete ◽

Splitting Tensile Strength ◽

Steel Fibers ◽

Reactive Powder Concrete ◽

Concrete Mechanical Properties ◽

Reactive Powder

Reactive Powder Concrete (RPC) is a type of ultra-high performance concrete, this dense composite material generally characterized by high cement content, high durability, low porosity, low water/cement ratio and in most cases contains steel fibers as new types of concrete appears, further investigation for their mechanical properties are needed. This work aims to give a better understanding of RPC behavior by deriving formulas to calculate the modulus of elasticity and the splitting tensile strength in relation with compressive strength and steel fibers content. This study is based on data obtained from the experimental investigation done in this work and from others pervious works. The parametric study is based mainly on the silica fume content which is used in four different ratios (12 %, 15 %, 20 % and 25 %), the use of micro steel fibers 15 mm in length, 0.2 mm in diameter and aspect ratio of 75 added in ratios of (0 %, 1 %, 1.5 % and 2 %), and water/cement in ratios of (16 %, 18 %, 20 % and 22 %), respectively. The proposed equations show a better behavior in comparison to some available equations that were used in the estimation of modulus of elasticity and splitting tensile strength of reactive powder concrete, the coefficient of variation for the proposed equations (COV) decrease to 10.677% and 10.455% respectively.

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Influence of Axial Compression Ratio on Seismic Behavior of Reactive Powder Concrete (RPC) Beam-Column Joints

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.597.312 ◽

2014 ◽

Vol 597 ◽

pp. 312-315 ◽

Cited By ~ 2

Author(s):

Yan Zhong Ju ◽

Chun Yu Li ◽

De Hong Wang

Keyword(s):

Bearing Capacity ◽

Axial Compression ◽

Compression Ratio ◽

Seismic Behavior ◽

Ultimate Bearing Capacity ◽

Reactive Powder Concrete ◽

Element Analysis ◽

Axial Compression Ratio ◽

Reactive Powder ◽

Axial Compressive Ratio

To explore the influence of axial compressive ratio on seismic behavior of reactive powder concrete(RPC) beam-column joints,this paper carry out RPC beam-column joints nonlinear finite element analysis,using software ABAQUS.The effect of different axial compression ratio on the ductility,energy dissipation capacity and bearing capacity are studied,based on hysteretic curves and skeleton curves of the components.The results show that,with the increase of axial compression ratio,skeleton curves of the components tend to be steep when the vertical load of beam ends exceed the peak point.The ultimate bearing capacity of the components are improved with the increasing of axial compression ratio which is less then 0.6,while the ultimate bearing capacity show a opposite trend when the axial compressive ratio exceed 0.6.

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Shear Strength of Steel Fiber Reinforced Reactive Powder Concrete & Geopolymer Concrete – A Comparison

Proceedings of International Web Conference in Civil Engineering for a Sustainable Planet ◽

10.21467/proceedings.112.43 ◽

2021 ◽

Author(s):

Aravind S Kumar ◽

Bharati Raj J ◽

Keerthy M Simon

Keyword(s):

Shear Strength ◽

Steel Fiber ◽

Load Capacity ◽

High Strength ◽

Steel Fibers ◽

Reactive Powder Concrete ◽

Polymer Concrete ◽

Geopolymer Concrete ◽

Fiber Reinforced ◽

Reactive Powder

Reactive Powder Concrete (RPC) is an ultra-high strength concrete composite prepared by the replacement of natural aggregates with quartz powder, silica fume and steel fibers. The use of RPC yields high strength, high ductile concrete with optimized material use and contributes to economic, sustainable and ecofriendly constructions. Past research has indicated that RPC offers significant improvement in the mechanical and physical properties owing to its homogenous composition with less defects of voids and microcracks. This leads to enhancement of ultimate load capacity of RPC members and results in superior ductility, energy absorption, tensile strain-hardening behavior, crack control capability and durability. Geo-polymer concrete (GPC) is a type of concrete that is made by reacting aluminate and silicate bearing materials with a caustic activator. Usually, waste materials such as fly ash or slag from iron and metal production are used, which helps lead to a cleaner environment. This paper attempts to review the effect of steel fibers on the shear strength of steel fiber reinforced RPC and compare the results with those of geopolymer concrete.

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Numerical Simulation of Failure Characteristics of Reactive Powder Concrete With Steel Fiber

Frontiers in Physics ◽

10.3389/fphy.2021.759513 ◽

2021 ◽

Vol 9 ◽

Author(s):

Xiaohu Zhang ◽

Songyuan Liu ◽

Gan Li ◽

Xiaofei Wang

Keyword(s):

Numerical Simulation ◽

Numerical Model ◽

Failure Modes ◽

Steel Fiber ◽

Numerical Models ◽

Triaxial Compression ◽

Mechanical Tests ◽

Steel Fibers ◽

Reactive Powder Concrete ◽

Reactive Powder

Steel fibers were delivered into the numerical concrete specimens using a mixed congruence method. A coplanar projection method is proposed to solve the problem of discriminating the crossing among steel fibers. Numerical models were built for reactive powder concrete (RPC) cylindrical specimens with 1 and 2% steel fiber. Comparisons between the numerical model and actual specimen slices show that the modified method has a good simulation effect. An improved anchor cable unit was used to simulate the bond–slip behavior between the steel fiber and concrete; the drawing of a single steel fiber was simulated. Then, the uniaxial compression, triaxial compression, and three-point bending of RPC specimens with 1% steel fiber were simulated, reproducing the concrete cracking and steel fiber slipping behaviors of RPC specimens. The failure modes of the numerical RPC specimen under various mechanical tests are consistent with the experimental results, proving the practicability and accuracy of this established numerical model. This study provides a foundation for the numerical simulation of RPC properties.

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