Study on the Increase of the Supporting Capacity of a Cement Milk Pile with Expansive Additives

In this study, an engineering characteristic test was conducted on cement milk using expansive additives during the construction of bored piles. Expansive additive mixtures with various mixing ratios were prepared according to the construction standards of the Korea Expressway Corporation. Segregation resistance, compressive strength, frictional resistance stress, scanning electron microscope images, porosity, and economic feasibility were analyzed. It was found that segregation effects due to expansive additive incorporation were insignificant, and it was confirmed that all specimens exceeded 0.5 N/mm2, the compressive strength standard of the Korea Expressway Corporation pile bearing capacity. Given a water–binder ratio of 83% mixed with 10% expansive additives, frictional resistance increased up to ~35%, skin friction force was significantly improved, and a cost-saving effect of up to ~33.24% was achieved.

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Fundamental Study on the Development of Sprayed High Performance Fiber Reinforced Cementitious Composites for Impact-Blast Resistant

10.20944/preprints201702.0042.v1 ◽

2017 ◽

Author(s):

Yun-Wang Choi ◽

Byung-Keol Choi ◽

Sung-Rok Oh ◽

Man-Seok Park

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

High Performance ◽

Drying Shrinkage ◽

High Volume ◽

Heat Of Hydration ◽

Economic Feasibility ◽

Fundamental Study ◽

Binder Ratio ◽

High Performance Fiber

In the recent concrete industry, high fluidity concrete is being widely used for the pouring of dense reinforced concrete. Normally, in the case of high fluidity concrete, it includes high binder contents, so it is necessary to replace part of the cement through admixtures such as fly ash to procure economic feasibility and durability. This study shows the mechanical properties and field applicability of high fluidity concrete that using mass of fly ash as alternative materials of cement. The high fluidity concrete mixed with 50% fly ash was measured to manufacture concrete that applies low water/binder ratio to measure the mechanical characteristics as compressive strength and elastic modulus. Also, in order to evaluate the field applicability, high fluidity concrete containing high volume fly ash was evaluated that fluidity, compressive strength, heat of hydration and drying shrinkage of concrete.

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A Study on the Evaluation of Field Application of High-Fluidity Concrete Containing High Volume Fly Ash

Advances in Materials Science and Engineering ◽

10.1155/2015/507018 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7

Author(s):

Yun-Wang Choi ◽

Man-Seok Park ◽

Byung-Keol Choi ◽

Sung-Rok Oh

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Drying Shrinkage ◽

High Volume ◽

Field Application ◽

Heat Of Hydration ◽

Economic Feasibility ◽

High Volume Fly Ash ◽

Alternative Materials ◽

Binder Ratio

In the recent concrete industry, high-fluidity concrete is being widely used for the pouring of dense reinforced concrete. Normally, in the case of high-fluidity concrete, it includes high binder contents, so it is necessary to replace part of the cement through admixtures such as fly ash to procure economic feasibility and durability. This study shows the mechanical properties and field applicability of high-fluidity concrete using mass of fly ash as alternative materials of cement. The high-fluidity concrete mixed with 50% fly ash was measured to manufacture concrete that applies low water/binder ratio to measure the mechanical characteristics as compressive strength and elastic modulus. Also, in order to evaluate the field applicability, high-fluidity concrete containing high volume fly ash was evaluated for fluidity, compressive strength, heat of hydration, and drying shrinkage of concrete.

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The Hydration, Mechanical, Autogenous Shrinkage, Durability, and Sustainability Properties of Cement–Limestone–Slag Ternary Composites

Sustainability ◽

10.3390/su13041881 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1881

Author(s):

Mei-Yu Xuan ◽

Yi Han ◽

Xiao-Yong Wang

Keyword(s):

Compressive Strength ◽

Electrical Resistivity ◽

Experimental Studies ◽

Autogenous Shrinkage ◽

Ultrasonic Pulse Velocity ◽

Ultrasonic Pulse ◽

Pulse Velocity ◽

Hydration Heat ◽

Granulated Blast Furnace Slag ◽

Binder Ratio

This study examines the hydration–mechanical–autogenous shrinkage–durability–sustainability properties of ternary composites with limestone filler (LF) and ground-granulated blast furnace slag (BFS). Four mixtures were prepared with a water/binder ratio of 0.3 and different replacement ratios varying from 0 to 45%. Multiple experimental studies were performed at various ages. The experimental results are summarized as follows: (1) As the replacement levels increased, compressive strength and autogenous shrinkage (AS) decreased, and this relationship was linear. (2) As the replacement levels increased, cumulative hydration heat decreased. At the age of 3 and 7 days, there was a linear relationship between compressive strength and cumulative hydration heat. (3) Out of all mixtures, the ultrasonic pulse velocity (UPV) and electrical resistivity exhibited a rapid increase in the early stages and tended to slow down in the latter stages. There was a crossover of UPV among various specimens. In the later stages, the electrical resistivity of ternary composite specimens was higher than plain specimens. (4) X-ray diffraction (XRD) results showed that LF and BFS have a synergistic effect. (5) With increasing replacement ratios, the CO2 emissions per unit strength reduced, indicating the sustainability of ternary composites.

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A Study on the Mechanical Properties for Ternary Polymer Blends

Journal of Materials Science Research ◽

10.5539/jmsr.v6n3p27 ◽

2017 ◽

Vol 6 (3) ◽

pp. 27

Author(s):

Awham M. Hameed

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Polymer Blends ◽

Hardness Test ◽

Flexural Behavior ◽

Ternary Blend ◽

Mixing Ratios ◽

Hardness Tests ◽

Ternary Polymer

In this work, two ternary polymer blends were prepared by mixing EP with (UP/PSR) and (PVC/PSR) respectively. Different mixing ratios were used (5, 10, 15 and 20) wt.% of the added polymers. Impact, tensile, compression, flexural and hardness tests were performed on the prepared blends. The results of testing showed that the first ternary blend A (EP/UP/PSR) records tensile strength values higher than that of the second ternary blend B (EP/ PVC/PSR). At 20wt.% of mixing, the blend B records higher impact strength than that of the blend A. There is large difference in the flexural behavior between A and B blends where the blend A records the highest value of flexural strength (F.S) at (5wt.%) while the blend B records the highest value of (F.S) at (20wt.%). From compression test, it is obvious that the values of compressive strength decrease of blend B more than that of the blend A as well as the same behavior can be obtained through the hardness test.

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Numerical Simulation of Bored Pile-Soil Interface Shear Performance

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.438-439.1427 ◽

2013 ◽

Vol 438-439 ◽

pp. 1427-1432

Author(s):

Qian Xu Liao ◽

Jin Cao ◽

Jun Wei Tang

Keyword(s):

Numerical Simulation ◽

Clayey Soil ◽

Frictional Resistance ◽

Measured Data ◽

Interface Shear ◽

Bored Pile ◽

Model Pile ◽

Shear Performance ◽

Bored Piles ◽

Soil Interface

This paper derives a numerical simulation of direct shearing test and model pile test based on the measured data of bored piles. Characteristics of the interface between bored pile and soil around it are analyzed. Laws of the magnitude and the distribution range of point resistance and frictional resistance of the bored piles in granular and clayey soil are obtained and the mechanism on them is explained.

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Research in the Preparation of Paving Bricks with Construction Garbage

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.712-715.917 ◽

2013 ◽

Vol 712-715 ◽

pp. 917-920

Author(s):

Lian Xi Wang ◽

Guang Hui Pan ◽

Fu Yong Li ◽

Hai Ming Wang ◽

Guo Zhong Li

Keyword(s):

Compressive Strength ◽

Flexural Strength ◽

Experimental Results ◽

Replacement Rate ◽

Coarse Aggregates ◽

Waste Concrete ◽

Fine Aggregates ◽

Binder Ratio ◽

Water Binder Ratio

Construction garbage paving bricks were made of recycled coarse and fine aggregates which were prepared by the waste concrete. The influence of replacement rate of recycled coarse aggregates, water-binder ratio and excitation agent dosage on the compressive strength and flexural strength of construction garbage paving bricks were researched. The experimental results show that optimum replacement rate of recycled coarse aggregates, water-binder ratio and excitation agent dosage were 100%, 0.43 and 1.5% respectively. In this proportion, the 7d, 28d compressive strength of the products were 15.6MPa, 37.5MPa respectively, and the 7d, 28d flexural strength were 2.0MPa, 4.3MPa respectively, which fit the requirements of the Cc30 level of compressive strength and the Cf4.0 level of flexural strength involved in JCT 446-2000 "concrete pavers".

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Utilization of Metakaolin and Calcite: Working Reversely in Workability Aspect—As Mineral Admixture in Self-Compacting Concrete

Advances in Civil Engineering ◽

10.1155/2018/4072838 ◽

2018 ◽

Vol 2018 ◽

pp. 1-12

Author(s):

Fatih Özcan ◽

Halil Kaymak

Keyword(s):

Compressive Strength ◽

High Strength ◽

High Volume ◽

Ultrasonic Pulse Velocity ◽

Ultrasonic Pulse ◽

Pulse Velocity ◽

Mineral Admixture ◽

Self Compacting Concrete ◽

Binder Ratio

In this work, utilization of metakaolin (MK) and calcite (C), working reversely in workability aspect, as mineral admixture in self-compacting concrete (SCC), was investigated. MK and C replaced cement in mass basis at various replacement ratios, separately and together. In total, 19 different SCCs were produced. Binder content and water to binder ratio were selected as 500 kg/m3 and 0.4, respectively. Workability tests including slump flow, T50, L-box, and V-funnel tests were performed. Consistency and setting times of binder paste were measured. While replacement of MK with cement increased the amount of plasticiser requirement, calcite worked reversely and decreased it. Reverse influence of MK and C on plasticiser requirement of SCC made possible to produce SCC at total 45% replacement ratio of MK and C together. Samples of SCC were cured in water at 20°C temperature. Compressive strengths of SCC samples were measured up to six months to evaluate the influence of MK and C, separately and together. Ultrasonic pulse velocity, abrasion, and capillary water absorption values of samples were determined at specified age. MK inclusion in concrete reduces workability, while C inclusion increases it. C and MK inclusion together remedied workability of concrete and enabled to produce SCC with high volume of admixtures. Furthermore, C incorporation increased one-day compressive strength, while MK incorporation reduced it in comparison with control concrete. In long term, C inclusion reduced compressive strength; however, MK inclusion increased it. C inclusion remedied one-day strength of concrete when it was used together with MK. MK inclusion remedied long-term compressive strength when it was used together with C and enabled to produce high-strength SCC with high volume of admixtures. SCC containing MK and C together showed better durability-related property.

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Steel Fibre Performance in Concrete with Expansive Additives under Restrained Hardening Conditions

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.788.30 ◽

2018 ◽

Vol 788 ◽

pp. 30-35

Author(s):

Arturs Lukasenoks ◽

Rolands Cepuritis

Keyword(s):

Compressive Strength ◽

Steel Fibre ◽

Single Fibre ◽

Steel Shell ◽

Concrete Compressive Strength ◽

Flexural Behaviour ◽

Pull Out ◽

Delamination Resistance ◽

Expansive Additive ◽

Standard Steel

Steel moulds in the form of a rigid cubical shell were developed in order to investigate single steel fibre pull-out resistance in concrete with expansive additive under restrained hardening conditions. The cubical shell (100 x 100 x 100 mm) with wall thickness of 5 mm was designed with two openings – a small 4 mm hole for fibre embedment in concrete and a larger opening for filling the concrete. Standard beam (100 x 100 x 400 mm) and cube (150 x 150 x 150 mm) samples were also manufactured and hardened under and without restrained conditions, where the restraint was realised by rigid standard steel moulds. All the restrained conditions realized by either the developed cubical steel shell (for single fibre pull-out) or existing beam and cube moulds simulate internal (from steel fibres in concrete) and external (from friction against sub-base) restraints that hinder expansion of the concrete due to the use of special expansive additives in a flooring slab structure installed on ground. Samples with a single hooked-end steel fibre (50 mm long and 0.75 mm in diameter), with and without expansive additive were manufactured and tested in the developed mould geometry. The results show that restrained expansion in concrete with expansive additives positively affects concrete compressive strength, single fibre pull-out and flexural behaviour. Concrete compressive strength increases by 7.5 %, single fibre delamination resistance increases by 24 %, the peak pull-out load by 10.8 % while the flexural strength increases by 3.1 %.

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Effective binder based on the artificial anhydrite for manufacturing of filling mixtures

MATEC Web of Conferences ◽

10.1051/matecconf/201819303048 ◽

2018 ◽

Vol 193 ◽

pp. 03048

Author(s):

Nadezda Galtseva ◽

Anfisa Bogdanova

Keyword(s):

Compressive Strength ◽

Setting Time ◽

Potassium Sulfate ◽

Technological Properties ◽

Start Time ◽

Filling Materials ◽

Binder Ratio ◽

Sufficient Set ◽

Concentrated Sulfuric Acid ◽

Derivation Method

The article exposes the results of research on the development of filling mixtures based on artificial anhydrite obtained after the interaction of concentrated sulfuric acid and limestone flour. The anhydrite derivation method has a significant impact on its properties and brings more options for the application. The key features of artificial anhydrite are high compressive strength which is more than 50 MPa and extended setting time which is more than 10 hours. In order to use it as a binder in the filling mixtures, it is necessary to modify properties of the anhydrite by integrating the hardening activators. In the relation to the study it was found that the optimal activator providing desirable setting start time (at least 2 hours) and a sufficient set of strength in the first 7 days of hardening is a mixture of 5% portland cement CEM I 42,5 and 1% of potassium sulfate, where 100% is the mass of binder. The additional inclusion of Melment F10 plasticizer in the amount of 0.4 to 1% of the binder ensures the achievement of the such parameters as the 0.3 water-binder ratio, setting start from 120 to 225 min, final setting time from 180 to 355 min, compressive strength after 24 hours from 6.9 to 13.3 MPa, after 7 days from 24.0 to 33.5 MPa. The microstructure of the binder has been analyzed and the modification options of the artificial anhydrite have been revealed in order to regulate its technical and technological properties., Two compounds of the filling mixture have been developed on the basis of the obtained binder, technical properties of compounds satisfy the maximum requirements for filling materials for depleted underground spaces. Research results have shown an opportunity and a prospectively of integrating the modified artificial anhydrite in structures of filling mixtures.

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Mechanical Properties and Environmental Evaluation of Ultra-High-Performance Concrete with Aeolian Sand

Materials ◽

10.3390/ma13143148 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3148 ◽

Cited By ~ 4

Author(s):

Hongyan Chu ◽

Fengjuan Wang ◽

Liguo Wang ◽

Taotao Feng ◽

Danqian Wang

Keyword(s):

Compressive Strength ◽

Environmental Impact ◽

Young’S Modulus ◽

High Performance ◽

High Performance Concrete ◽

Young's Modulus ◽

Ultra High Performance Concrete ◽

Aeolian Sand ◽

Binder Ratio ◽

Water Binder Ratio

Ultra-high-performance concrete (UHPC) has received increasing attention in recent years due to its remarkable ductility, durability, and mechanical properties. However, the manufacture of UHPC can cause serious environmental issues. This work addresses the feasibility of using aeolian sand to produce UHPC, and the mix design, environmental impact, and mechanical characterization of UHPC are investigated. We designed the mix proportions of the UHPC according to the modified Andreasen and Andersen particle packing model. We studied the workability, microstructure, porosity, mechanical performance, and environmental impact of UHPC with three different water/binder ratios. The following findings were noted: (1) the compressive strength, flexural strength, and Young’s modulus of the designed UHPC samples were in the ranges of 163.9–207.0 MPa, 18.0–32.2 MPa, and 49.3–58.9 GPa, respectively; (2) the compressive strength, flexural strength, and Young’s modulus of the UHPC increased with a decrease in water/binder ratio and an increase in the steel fibre content; (3) the compressive strength–Young’s modulus correlation of the UHPC could be described by an exponential formula; (4) the environmental impact of UHPC can be improved by decreasing its water/binder ratio. These findings suggest that it is possible to use aeolian sand to manufacture UHPC, and this study promotes the application of aeolian sand for this purpose.

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