Characterization of Tensile Behavior of Fresh Cementitious Materials

This study investigated the recovery stress and bond resistance of cold drawn crimped SMA fiber using two different initial diameters of 1.0 and 0.7 mm. These characteristics are important to the active prestressing effect and crack-closing of the fiber. NiTi SMA fiber was used for the cold drawing, and then crimped shapes were manufactured with various wave heights. After that, tensile, recovery, and pullout tests were conducted. The cold drawn crimped fiber showed softening tensile behavior more clearly than the cold drawn straight fiber when not subjected to heating, whereas they had the same tensile behavior under heating. The recovery stress and the residual stress of the crimped fibers were less than those of the straight fiber with the same diameter. Moreover, crimped fibers with a large diameter and higher wave height would induce more recovery stress and residual stress. The maximum pullout resistance of the crimped fiber was a function of the wave depth, embedded length, yield strength, and flexural rigidity of the fiber.

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Characterization of the Tensile Behavior of Expanded Polystyrene Foam as a Function of Density and Strain Rate

Advanced Engineering Materials ◽

10.1002/adem.202000794 ◽

2020 ◽

Vol 22 (12) ◽

pp. 2000794

Author(s):

Dimitris Zouzias ◽

Guido De Bruyne ◽

Ramon Miralbes ◽

Jan Ivens

Keyword(s):

Strain Rate ◽

Expanded Polystyrene ◽

Tensile Behavior ◽

Polystyrene Foam ◽

Expanded Polystyrene Foam

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Cementitious Sealing Material: 3D Digital Image Based Characterization of Pore Size Distribution and Modeling of Transport Properties

Volume 6: Polar and Arctic Sciences and Technology; Offshore Geotechnics; Petroleum Technology Symposium ◽

10.1115/omae2013-10954 ◽

2013 ◽

Author(s):

Neven Ukrainczyk ◽

Eduardus A. B. Koenders ◽

Klaas van Breugel

Keyword(s):

Pore Size ◽

Transport Properties ◽

Digital Image ◽

Oil And Gas ◽

Transport Model ◽

Medial Axis ◽

Three Dimensional ◽

Cementitious Materials ◽

Pore Size Distributions

Exhausted oil and gas reservoirs are one of the most potential storage facilities to sequestrate the worlds CO2. These reservoirs are sealed with cementitious materials, that should have a long time performance. Therefore, this paper emphasizes the characterization of the evolving capillary pore network and transport properties of the cementitious microstructure used to seal the wellbore. The Hymostruc numerical model is employed to simulate the development of an evolving virtual microstructure of cementitious materials. The simulated 3D microstructures were then digitized to form a matrix of cubic voxels. The pore-size distributions of the obtained virtual microstructures were calculated using a combination of three-dimensional digital image processing algorithms: 1) distance transform and 2) medial axis thinning algorithm to obtain a 3D skeleton of the pore structure. Transport properties of the simulated microstructures are analyzed employing a finite difference 3D transport model. The modeling results are compared with available literature results.

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The Use of SEM and Other Complimentary Techniques for the Determination of Properties of Cementitious Materials

Microscopy Today ◽

10.1017/s1551929500071066 ◽

1992 ◽

Vol 00 (8) ◽

pp. 4-4 ◽

Cited By ~ 1

Author(s):

Eric A. Draper ◽

Jan Skalny

Keyword(s):

Building Materials ◽

State Of The Art ◽

Raw Materials ◽

Cementitious Materials ◽

Modern State ◽

Microscopic Evaluation ◽

The World ◽

Cost Effect

The need for continued rehabilitation of our concrete infrastructure has lead to the adaptation of modern “state-of-the-art” analytical methods for the characterization of concrete and other cementitious materials. Some of these techniques have not, until relatively recently, been commonly associated with the evaluation of concrete but are very useful both as tools for quality assurance and in the determination of the extent of existing damage. The technique of interest here is the coordinated electron-optical microscopic evaluation of concrete.Concrete is the most widely used building material in the world. Contrary to popular belief, concrete is not inert but chemically very complex and dynamic. While it is true that, pound for pound, concrete and its raw materials (cement, aggregate and water} are the most inexpensive building materials available for construction, it is also true that it responds to its environment in numerous and sometimes very subtle ways. These responses may sometimes result in a loss of durability and tremendous amounts of time and money being expended while searching for the cause(s) of the problem and providing a cost-effect solution A quick survey of any large metropolitan area and the on-going construction repairs to highways and bridge decks there will quickly confirm this.

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Sol Gel Characterization of Nano Kaolin

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.856.285 ◽

2013 ◽

Vol 856 ◽

pp. 285-289

Author(s):

M.S. Muhd Norhasri ◽

M.S. Hamidah ◽

A.G. Abd Halim ◽

A. Mohd Fadzil

Keyword(s):

Particle Size ◽

Surface Area ◽

Sol Gel ◽

High Energy ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Process Time ◽

Strength And Durability ◽

Clay Kaolin

Nano kaolin is product from kaolin also known as white clay. Kaolin was established as supplementary cementitious materials in concrete. The inclusion of kaolin in concrete enhances strength and durability properties and prolongs concrete life span. In this research, nanokaolin will be develop by using sol gel technique by that involves high energy milling. The process of milling been influenced by time of milling, ball and jar type. Ceramic type Zirconia (Zi) is been used as jar and ball type in this process. Time of milling was set from four (4) hours and one (1) days. Sample will be analyse by using particle size analyser to see the particle size and surface area of kaolin. From the result shows the optimum milling period for nanokaolin is one day base on particle size compare to 4 hours. Furthermore, one day milling produces a massive increment of surface area compare to others. In conclusion, one day can be considered as the optimum cycle time in the production of nano kaolin.

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