Experimental Study on Crack Development of Rock Specimens by Freezing and Thawing Cycles

The experiments of concrete in seawater under 0, 25, 50, 75 and 100 freezing-thawing cycles were performed using fast freezing and thawing method. Appling large concrete static and dynamic triaxial test system, the influence of freezing and thawing cycles on compressive strength and strain at peak stress point of concrete in seawater were detected, and then simple mathematical expressions were established.

Download Full-text

The Processes of Crack Development in Saturated Welded Tuff Specimen by Freezing and Thawing Cycles.

Shigen-to-Sozai ◽

10.2473/shigentosozai.116.7 ◽

2000 ◽

Vol 116 (1) ◽

pp. 7-12 ◽

Cited By ~ 2

Author(s):

Tiancheng CHEN ◽

Noriyasu MORI ◽

Takashi GOTO ◽

Teruyuki SUZUKI ◽

Masahiro HIRAMATSU

Keyword(s):

Crack Development ◽

Freezing And Thawing ◽

Welded Tuff ◽

Freezing And Thawing Cycles

Download Full-text

Experimental study of σ - ε diagrams of concrete under uniaxial compression and the influence of freezing and thawing cycles on the form of the diagrams

Вестник гражданских инженеров ◽

10.23968/1999-5571-2020-17-4-80-88 ◽

2020 ◽

Vol 17 (4) ◽

pp. 80-88

Author(s):

V. M. Popov ◽

◽

M. G. Plyusnin ◽

Keyword(s):

Experimental Study ◽

Compressive Strength ◽

Uniaxial Compression ◽

Reinforced Concrete Structures ◽

Deformation Characteristics ◽

Freezing And Thawing ◽

Coefficients Of Variation ◽

Initial Modulus ◽

Compressive Strength Of Concrete ◽

Freezing And Thawing Cycles

As a result of the experimental study, there was estimated the variability of the form of complete diagrams σ-ε of concrete under uniaxial compression. It is shown that the coefficients of variation of concrete deformation characteristics are comparable with the coefficient of variation of strength within one concrete class in terms of compressive strength. It was found out that the effect of freezing and thawing cycles leads not only to a decrease in the compressive strength of concrete, but also to a decrease in the ultimate deformations and the initial modulus of elasticity. Thus, when using diagram methods for calculating reinforced concrete structures, it is necessary to take into account the influence of variability not only in the strength, but also in the deformation characteristics of concrete.

Download Full-text

An experimental study of crack development in flexural reinforced concrete members

IABSE Symposium, Vancouver 2017: Engineering the Future ◽

10.2749/vancouver.2017.3099 ◽

2017 ◽

Author(s):

Annette Beedholm Rasmussen ◽

Bjarke Würtz Sørensen ◽

Mikkel Skov ◽

Peter Kolt Rasmussen ◽

Lars Germa Hagsten

Keyword(s):

Experimental Study ◽

Reinforced Concrete ◽

Crack Development ◽

Concrete Members

Download Full-text

EXPERIENCE OF APPLICATION HIGH PERFORMANCE CEMENT COMPOSITES FOR CREATING DURABLE SCULPTURAL ELEMENTS

Environment Technology Resources Proceedings of the International Scientific and Practical Conference ◽

10.17770/etr2017vol3.2609 ◽

2017 ◽

Vol 3 ◽

pp. 286

Author(s):

Genadijs Sahmenko ◽

Sandis Aispurs ◽

Aleksandrs Korjakins

Keyword(s):

Water Absorption ◽

High Performance ◽

Cement Composite ◽

Cement Composites ◽

Freezing And Thawing ◽

Initial Water ◽

Good Potential ◽

Freezing And Thawing Cycles ◽

Material Ductility ◽

And Control

Traditionally, sculptural and decorative elements of building facades are created from mortar mixes based on lime, gypsum or Portland cement. Generally these materials have porous and permeable structure, which determines their accelerated degradation, especially in the aggressive environment of modern cities. High performance cement composites (HPCC) have been considered for production and restoration of sculptural elements in historical buildings. For this purpose, fine-graded, multi-component and highly workable mixes were elaborated. Mix compositions were modified with micro-fillers, plasticizing and stabilizing admixtures, as well as fibers to improve material ductility and control shrinkage cracking. Basic mechanical properties and durability (such as water absorption, frost resistance) were determined and two types of HPCC were compared (>50 MPa: HPCC and >120 MPa: UHPCC). It has been confirmed that cement composite mixes are characterized by self-consolidating effect, high compressive strength, extremely high resistance versus freezing and thawing cycles and low water absorption. Surface quality was evaluated and initial water absorption (tube tests) were performed for laboratory samples and real sculptural elements after 5 years of exploitation. The results confirmed good potential for using HPCC for creating more attractive and durable architectural shapes and façade elements compared to elements made using traditional cement and lime mortar.

Download Full-text

Experimental study of wastewater treatment containing sulfuric acid solutions using freezing and thawing method

10.5004/dwt.2021.26606 ◽

2021 ◽

Vol 211 ◽

pp. 141-152

Author(s):

M. Guessous ◽

A. Rich ◽

S. Mountadar ◽

F.Z. Karmil ◽

J. El Hajri ◽

...

Keyword(s):

Experimental Study ◽

Wastewater Treatment ◽

Sulfuric Acid ◽

Acid Solutions ◽

Freezing And Thawing ◽

Sulfuric Acid Solutions

Download Full-text

Experimental Study on Freezing and Thawing Cycles of Shrinkage-Compensating Concrete with Double Expansive Agents

Materials ◽

10.3390/ma13081850 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1850

Author(s):

Jinjun Guo ◽

Ting Guo ◽

Shiwei Zhang ◽

Yan Lu

Keyword(s):

Frost Resistance ◽

Large Scale ◽

Mass Loss Rate ◽

Test Results ◽

Freezing And Thawing ◽

Expansive Agent ◽

Hydraulic Concrete ◽

Mix Proportion ◽

Three Stages ◽

Freezing And Thawing Cycles

The freezing and thawing of construction concrete is becoming an increasingly important structural challenge. In this study, a shrinkage-compensating concrete based on a double expansive admixture was developed and its frost resistance was assessed through rapid freezing and thawing cycling. The frost resistance of the concrete was derived through the measurement and calculation of the relative dynamic modulus of elasticity (RDME) and the mass loss rate (MLR), and the freezing- and thawing-cycle microstructures and products of concretes with different expansive agents were analyzed using scanning electron microscopy (SEM). It was shown that changes in the properties of the concrete under freezing and thawing could be divided into three stages: slow-damage stage, fast-damage stage, and stable stage. Compared to concrete without an expansive agent, a single-expansive-agent concrete demonstrated excellent frost resistance during the slow-damage stage, but the frost resistance rapidly decreased during the fast-damage age. After 150 cycles (the stable-damage stage), the concrete with a U-type expansive agent (UEA): MgO expansive agent (MEA) mix proportion of 2:1 had the best frost resistance, with RDME and MLR values 17.35% higher and 25.1% lower respectively, than that of an expansive-agent-free concrete. These test results provide a basis for the study of frost resistance in large-scale hydraulic concrete structures.

Download Full-text

Permeability and volume changes in till due to cyclic freeze/thaw

Canadian Geotechnical Journal ◽

10.1139/t98-015 ◽

1998 ◽

Vol 35 (3) ◽

pp. 471-477 ◽

Cited By ~ 123

Author(s):

Peter Viklander

Keyword(s):

Soil Structure ◽

Void Ratio ◽

Vertical Direction ◽

Rigid Wall ◽

Freezing And Thawing ◽

Volume Changes ◽

Freeze Thaw ◽

Fine Grained ◽

Loose Soil ◽

Freezing And Thawing Cycles

A fine-grained nonplastic till was compacted in the laboratory in three types of rigid wall permeameters, having a volume of 0.4, 1.5, and 25 dm3, respectively, and, was thereafter exposed to a maximum of 18 freezing and thawing cycles. The permeabilities in the vertical direction of saturated samples were measured in unfrozen soil as well as in thawed soil. The results show that the permeabilities changed after freezing and thawing. The magnitude of the changes in this study were in the range 0.02-10 times after freeze/thaw compared with the unfrozen soil. Soil exhibited volume changes subsequent to freeze/thaw. The volume typically decreased for an initially loose soil and increased for a dense soil. Independent of whether the initial soil structure was loose or dense, a constant "residual" void ratio, eres, was obtained after 1-3 cycles. For the soil investigated, the residual void ratio ranged from 0.31 to 0.40.Key words: till, fine-grained, non plastic, permeability, freeze/thaw, residual void ratio.

Download Full-text