Model of Compressive Strength Degradation of Concrete under Both Freeze-Thaw Cycles and Compressive Loads

Analyze the influence factors of mix proportion affecting concrete freeze-thaw damage. Use the five main performance indexes of the concrete, which are compressive strength, strength of extension, impermeability grade, and frost resistance grade and per unit volume cost concrete, as the objective function of multi-objective optimization equation. Invoke the fgoalattain function in the MATLAB Optimization Toolbox to solve. The optimized parameters of mix proportion of frost resistance construction of unit concrete in cold region are: concrete 1532.6kg, water 910kg, sand 5510.6kg, 5-20mm cobblestone 3747.2kg、20-40mm cobblestone 3658.6kg、40-80mm cobblestone 4733.5kg、80-150mm cobblestone 4738.1kg, and the dosage of water reducing agent is 7.3kg.

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Strength Time–Varying and Freeze–Thaw Durability of Sustainable Pervious Concrete Pavement Material Containing Waste Fly Ash

Sustainability ◽

10.3390/su11010176 ◽

2018 ◽

Vol 11 (1) ◽

pp. 176 ◽

Cited By ~ 1

Author(s):

Hanbing Liu ◽

Guobao Luo ◽

Longhui Wang ◽

Yafeng Gong

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Flexural Strength ◽

Pervious Concrete ◽

Early Age ◽

Pavement Materials ◽

Freeze Thaw ◽

Replacement Method ◽

Porosity And Permeability ◽

Volume Method

Pervious concretes, as sustainable pavement materials, have great advantages in addressing a number of environmental issues. Fly ash, as the industrial by-product waste, is the most commonly used as cement substitute in concrete. The objective of this paper is to study the effects of waste fly ash on properties of pervious concrete. Fly ash was used to replace cement with equivalent volume method at different levels (3%, 6%, 9%, and 12%). The control pervious concrete and fly ash modified pervious concrete were prepared in the laboratory. The porosity, permeability, compressive strength, flexural strength, and freeze–thaw resistance of all mixtures were tested. The results indicated that the addition of fly ash decreased the early-age (28 d) compressive strength and flexural strength, but the long-term (150 d) compressive strength and flexural strength of fly ash modified pervious concrete were higher than that of the early-age. The adverse effect of fly ash on freeze–thaw resistance of pervious concrete was observed when the fly ash was added. The porosity and permeability of all pervious concrete mixtures changed little with the content of fly ash due to the use of equal volume replacement method. Although fly ash is not positive to the properties of pervious concrete, it is still feasible to apply fly ash as a substitute for cement in pervious concrete.

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Physical Properties of Building Blocks from Hemp Shives Aggregate and Cementitious Binder, Manufactured in the Expanded Clay (Vibro Pressing) Production Line

Materials Science Forum ◽

10.4028/www.scientific.net/msf.908.118 ◽

2017 ◽

Vol 908 ◽

pp. 118-122 ◽

Cited By ~ 1

Author(s):

Giedrius Balčiūnas ◽

Viktor Kizinievič ◽

Justinas Gargasas

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Compressive Strength ◽

Physical Properties ◽

Production Line ◽

Scientific Literature ◽

Building Blocks ◽

Freeze Thaw ◽

Cementitious Binder ◽

Pressing Technology

Scientific literature mostly aims at investigation of composites with fibre hemp shives (FHS) aggregate and lime binder, although, such materials are characterised by pretty low mechanical properties. In order to obtain higher mechanical properties of a composite, it is appropriate to use cementitious binder. This work investigates physical properties of blocks from hemp shives aggregate and cementitious binder, manufactured in the expanded clay production line using vibro pressing technology. Following properties of the blocks are determined: freeze-thaw resistance, compressive strength, thermal conductivity and density. Thermal resistance according to EN ISO 6946 for the block with cavities is calculated as well. It is found that compressive strength of FHS-cement blocks may be up to 3.18 MPa when the density is of ~850 kg/m3 and thermal conductivity up to 0.135 W/(m∙K). It is found as well that the decrease of compressive strength is 8.7% after 25 freeze-thaw cycles.

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Study on Strength Characteristics of Solidified Contaminated Soil under Freeze-Thaw Cycle Conditions

Advances in Civil Engineering ◽

10.1155/2018/8654368 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 4

Author(s):

Qiang Wang ◽

Jinyang Cui

Keyword(s):

Electron Microscopy ◽

Compressive Strength ◽

Contaminated Soils ◽

Unconfined Compressive Strength ◽

Freeze Thaw ◽

Thaw Cycle ◽

Strength Tests ◽

Freeze Thaw Cycle ◽

Microcosmic Mechanism ◽

Scanning Electron

Cement solidification/stabilization is a commonly used method for the remediation of contaminated soils. The stability characteristics of solidified/stabilized contaminated soils under freeze-thaw cycle are very important. A series of tests, which include unconfined compressive strength tests, freeze-thaw cycle tests, and scanning electron microscopy (SEM) tests, are performed to study the variation law of strength characteristics and microstructure. It aims at revealing the microcosmic mechanism of solidified/stabilized Pb2+ contaminated soils with cement under freeze-thaw cycle. The results show that the unconfined compressive strength of the contaminated soils significantly improved with the increase of the cement content. The unconfined compressive strength of stabilized contaminated soils first increases with the increase of times of freeze-thaw cycle, and after reaching the peak, it decreases with the increase of times of freeze-thaw cycle. The results of the scanning electron microscopy tests are consistent with those of the unconfined compressive strength tests. This paper also reveals the microcosmic mechanism of the changes in engineering of the stabilized contaminated soils under freeze-thaw cycle.

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Degradation of Mechanical Behavior of Sandstone under Freeze-Thaw Conditions with Different Low Temperatures

Applied Sciences ◽

10.3390/app112210653 ◽

2021 ◽

Vol 11 (22) ◽

pp. 10653

Author(s):

Jingwei Gao ◽

Chao Xu ◽

Yan Xi ◽

Lifeng Fan

Keyword(s):

Compressive Strength ◽

Elastic Modulus ◽

Mechanical Behavior ◽

Energy Absorption ◽

Uniaxial Compressive Strength ◽

Dynamic Strength ◽

Freezing Temperature ◽

P Wave ◽

Freeze Thaw ◽

P Wave Velocity

This study investigated the effects of freezing temperature under freeze-thaw cycling conditions on the mechanical behavior of sandstone. First, the sandstone specimens were subjected to 10-time freeze-thaw cycling treatments at different freezing temperatures (−20, −40, −50, and −60 °C). Subsequently, a series of density, ultrasonic wave, and static and dynamic mechanical behavior tests were carried out. Finally, the effects of freezing temperature on the density, P-wave velocity, stress–strain curves, static and dynamic uniaxial compressive strength, static elastic modulus, and dynamic energy absorption of sandstone were discussed. The results show that the density slightly decreases as temperature decreases, approximately by 1.0% at −60 °C compared with that at 20 °C. The P-wave velocity, static and dynamic uniaxial compressive strength, static elastic modulus, and dynamic energy absorption obviously decrease. As freezing temperature decreases from 20 to −60 °C, the static uniaxial compressive strength, static elastic modulus, dynamic strength, and dynamic energy absorption of sandstone decrease by 16.8%, 21.2%, 30.8%, and 30.7%, respectively. The dynamic mechanical behavior is more sensitive to the freezing temperature during freeze-thawing cycling compared with the static mechanical behavior. In addition, a higher strain rate can induce a higher dynamic strength and energy absorption.

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The effect of the pre-wetting of expanded clay aggregate on the freeze-thaw resistance of the expanded clay aggregate concrete

Studia Geotechnica et Mechanica ◽

10.2478/sgem-2020-0011 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Michał Piotr Musiał ◽

Filip Grzymski ◽

Tomasz Trapko

Keyword(s):

Compressive Strength ◽

Moisture Content ◽

Concrete Compressive Strength ◽

Aggregate Concrete ◽

Freeze Thaw ◽

Concrete Mix Design ◽

In Series ◽

Resistance Criterion ◽

Mixing Water ◽

Nominal Amount

AbstractThis paper presents experimental research on expanded clay aggregate concrete. The aim of the investigations was to determine if the pre-wetting of expanded clay aggregate has an effect on the freeze-thaw durability of the expanded clay aggregate concrete. Five concrete series based on the same concrete mix design were made and tested. The degree of pre-wetting of the aggregate was varied: dry aggregate was used in the first series, aggregate with a moisture content of 10% was used in series IA and IB and aggregate with a moisture content of 25% was used in series IIA and IIB. Also the approach to the production process was varied: in series A the water contained in the aggregate was taken into account in the global water-cement ratio (consequently a reduced amount of water was added to the mix), whereas in series B the nominal amount of water was added to the mix (as in the case of dry aggregate). The freeze-thaw resistance criterion was based on the assessment of the decrease of compressive strength and increase in weight loss after exposure to freeze-thaw cycles. The expanded clay aggregate concrete's strength and mass decrements caused by freeze-thaw cycling were used as the measure of its freeze-thaw resistance. The investigations have shown that the pre-wetting of expanded clay aggregate has an effect on the freeze-thaw durability of the expanded clay aggregate concrete. The differences of concrete compressive strength decrease related to freeze-thaw durability may be 2 to 5 times greater when inadequate method of calculating mixing water for concrete is used.

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PENELITIAN UJI KUAT TEKAN BETON DENGAN MEMANFAATKAN LIMBAH AMPAS TEBU DAN ZAT ADDITIF SIKACIM BONDING ADHESIVE

Jurnal Manajemen Teknologi & Teknik Sipil ◽

10.30737/jurmateks.v2i1.385 ◽

2019 ◽

Vol 2 (1) ◽

pp. 1

Author(s):

Agil Dwi Krisna ◽

Sigit Winarto ◽

Ahmad Ridwan

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Concrete Mixture ◽

High Compressive Strength ◽

Compressive Loads ◽

Average Compressive Strength

Concrete has the disadvantage of having a low tensile strength and convincing brittle beams with steel inscriptions to anticipate. In this study, the concrete mixture was given additional bagasse and additives of cycacim bonding. This addition was carried out to study and study the effect of bagasse on the compressive strength of normal k300 concrete by replacing bagasse by 0%, 5%, 10% and 15% in compressive loads. Compressive strength specimens in the form of cubes with a size of 15 cm x 15 cm x 15 cm. Testing is done after 28 days. Concrete with increased bagasse of 5% is better able to produce high compressive strength values than others. The addition of bagasse resulted in an average compressive strength of 5%, 229.64 kg / cm2, 10%, 190.35 kg / cm2, 15%, 160.87 kg / cm2.Beton mempunyai kelemahan yaitu mempunyai kuat tarik yang rendah dan bersifat getas sehingga beton diberi tulangan baja untuk mengantisipasinya. Pada penelitian ini, campuran beton diberi bahan tambahan ampas tebu dan zat additif sikacim bonding adhesive. Penambahan ini dilakukan untuk mempelajari dan mengetahui pengaruh ampas tebu terhadap kuat tekan pada beton mutu normal k300 dengan penambahan ampas tebu sebesar 0%, 5%, 10% dan 15% pada beban tekan. Benda uji kuat tekan berbentuk kubus dengan ukuran 15 cm x 15 cm x 15 cm. Pengujian dilakukan setelah 28 hari. Beton dengan penambahan ampas tebu 5% lebih mampu menghasilkan nilai kuat tekan tinggi dari pada yang lainya. Penambahan ampas tebu menghasilakan kuat tekan rata-rata yaitu 5%,229,64 kg/cm2, 10%,190,35 kg/cm2, 15%,160,87kg/cm2.

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Performance Deterioration of High Strength Concrete under Mixed Erosion and Freeze-Thaw Cycling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.163-167.1655 ◽

2010 ◽

Vol 163-167 ◽

pp. 1655-1660

Author(s):

Jian Zhang ◽

Bo Diao ◽

Xiao Ning Zheng ◽

Yan Dong Li

Keyword(s):

Compressive Strength ◽

Elastic Modulus ◽

Mass Loss ◽

Modulus Of Elasticity ◽

Dynamic Modulus ◽

High Strength Concrete ◽

High Strength ◽

Freeze Thaw ◽

Strength Concrete ◽

Dynamic Modulus Of Elasticity

The mechanical properties of high strength concrete(HSC) were experimentally investigated under mixed erosion and freeze-thaw cycling according to ASTM C666(Procedure B), the erosion solution was mixed by weight of 3% sodium chloride and 5% sodium sulfate. The mass loss, relative dynamic modulus of elasticity, compressive strength, elastic modulus and other relative data were measured. The results showed that with the increasing number of freeze-thaw cycles, the surface scaled more seriously; the mass loss, compressive strength and elastic modulus continued to decrease; the relative dynamic modulus of elasticity increased slightly in the first 225 freeze-thaw cycles, then decreased in the following 75 cycles; the corresponding strain to peak stress decreased with the increase of freeze-thaw cycles. After 200 cycles, the rate of deterioration of concrete accelerated obviously.

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