Mechanical properties of young concrete: Part I: Experimental results related to test methods and temperature effects

In order to research on mechanical properties of flexible suspension bridges, a geometric nonlinear analysis method was used to simulate on the experimental results, and carried on static loading test finally. In the loading test process, the deformations were measured in critical section of the suspension bridge, and displacement values of measured are compared with simulation values of the finite element simulation. Meanwhile the deformations of the main cable sag are observed under classification loading, the results show that the main cable sag increment is basically linear relationship with the increment of mid-span loading and tension from 3L/8 and 5L/8 to L/2 section, the main cable that increasing unit sag required mid-span loads and tension are gradually reduce in near L/4 and 3L/4 sections and gradually increase in near L/8 and 7L/8 sections and almost equal in near L/2, 3L/8 and 5L/8 sections. From the experimental results, the flexible suspension bridge possess good mechanical properties.

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Application of Small Punch Test to Evaluate Tensile Properties of SA213T22 Grade Boiler Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.830-831.191 ◽

2015 ◽

Vol 830-831 ◽

pp. 191-194

Author(s):

M. Venkateswara Rao

Keyword(s):

Mechanical Properties ◽

High Temperature ◽

Tensile Properties ◽

Test Methods ◽

Uniaxial Tensile ◽

Test Results ◽

Small Punch Test ◽

Small Punch ◽

Punch Test ◽

Aging Phenomena

Conventional tensile test methods are used for service exposed high temperature boiler tubes to evaluate the deterioration in mechanical properties such as tensile strength, yield strength and percentage elongation. The mechanical properties are required to be evaluated periodically as the boiler components undergo material degradation due to aging phenomena. The aging phenomena occurs due to continuous exposure of tubes to high temperature & pressure steam prevailing inside the tubes and high temperature exposure to corrosive combustible gases from the external surfaces within the boiler.A recent developed new technique called small punch testing has been used to evaluate the tensile properties of SA 213T22 grade steel predominantly exists in super-heater and re-heater sections of boiler. The small punch tests have been carried out on the miniature disk shaped specimens of diameter of 8.0 mm and 0.5 mm thickness extracted from both the new and service exposed tubes. Conventional uniaxial tensile tests on standard specimens from the same tube material have also been performed for comparison. The service exposed tubes showed considerable loss in mechanical properties in both the conventional and small punch test results. Correlations of tensile properties have been obtained based on the comparative analysis of both small punch and uniaxial tensile test results. Further, the study showed that an appropriate empirical relation could be generated for new and service exposed materials between both the techniques. Conventional test methods require large quantity of material removal for test samples from in-service components whereas small punch test method needs only a miniature sample extraction. This small punch test technique could also be extended to evaluate the thicker section boiler components such as pipelines and headers in the boiler as a part of remaining life assessment study. Also this technique could be a useful tool to any metallic component where large quantity of sample removal may be difficult or may not be feasible.

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Numerical and experimental evaluation of masonry prisms by finite element method

Revista IBRACON de Estruturas e Materiais ◽

10.1590/s1983-41952017000200010 ◽

2017 ◽

Vol 10 (2) ◽

pp. 477-508 ◽

Cited By ~ 2

Author(s):

C. F.R. SANTOS ◽

R. C. S. S. ALVARENGA ◽

J. C. L. RIBEIRO ◽

L. O CASTRO ◽

R. M. SILVA ◽

...

Keyword(s):

Mechanical Properties ◽

Finite Element Method ◽

High Strength Concrete ◽

Numerical Models ◽

High Strength ◽

Experimental Tests ◽

Experimental Results ◽

Concrete Blocks ◽

Micro Modeling ◽

Modeling Strategy

Abstract This work developed experimental tests and numerical models able to represent the mechanical behavior of prisms made of ordinary and high strength concrete blocks. Experimental tests of prisms were performed and a detailed micro-modeling strategy was adopted for numerical analysis. In this modeling technique, each material (block and mortar) was represented by its own mechanical properties. The validation of numerical models was based on experimental results. It was found that the obtained numerical values of compressive strength and modulus of elasticity differ by 5% from the experimentally observed values. Moreover, mechanisms responsible for the rupture of the prisms were evaluated and compared to the behaviors observed in the tests and those described in the literature. Through experimental results it is possible to conclude that the numerical models have been able to represent both the mechanical properties and the mechanisms responsible for failure.

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