Buildings and civil engineering works. Sealants. Determination of tear resistance

Abstract The application of geodetic methods to examine structures consists in the determination of their displacements relative to an established geodetic reference datum or in the definition of the geometry of their individual components. Such examinations form a picture of changes happening between specific points in time. Modern measurement technologies used in geodetic engineering enable undertaking more and more challenging measurements with increasing accuracy. The purpose of this article is to present a measurement technique involving a Leica TDRA 6000 total station to measure displacements in engineering structures. The station features a direct drive technology to achieve an accuracy of 0.25 mm in 3-dimensional measurements. Supported by appropriate software, the unit makes a perfect instrument for the monitoring of civil engineering structures. The article presents the results of measurement of static and dynamic displacements in a few engineering structures. The measurements were carried out both in laboratory conditions and on actual, operated civil engineering structures.

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The Assessment of Reaction to Fire of Crushed Straw

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.824.148 ◽

2016 ◽

Vol 824 ◽

pp. 148-155 ◽

Cited By ~ 1

Author(s):

Jiří Teslík ◽

Martina Vodičková ◽

Kristýna Kutilová

Keyword(s):

Building Materials ◽

Civil Engineering ◽

Engineering Industry ◽

Sound Insulation ◽

Technical Parameters ◽

Fire Characteristics ◽

Full Utilization ◽

Preliminary Classification

To full utilization of crushed straw in civil engineering industry is necessary to know its technical parameters. During previous projects on VŠB – TUO, Faculty of Civil Engineering have found parameters like settlement, thermal conductivity or airborne sound insulation. The research on these parameters have had favorable results, therefore the research is going on and other characteristics of crushed straw are finding out. These days the research team deals with determination of important fire characteristics of crushed straw. Fire characteristics play substantial character by building materials and their design in buildings. Nature materials are generally regarded as flammable. If some material is pressed, the same rule as in the phonebook – if you ignite one sheet of paper, it burns. But if you try to ignite the whole phonebook, it will be not so easy. This article is reported the first step of research on the reaction to fire. This is the preliminary classification of crushed straw into reaction to fire. The test was made according to methods which are described below. There are some changes in methods due to different structures of crushed straw.

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Determination of the Resistance of Vulcanized Rubber to Tearing

Rubber Chemistry and Technology ◽

10.5254/1.3546411 ◽

1938 ◽

Vol 11 (4) ◽

pp. 689-705

Author(s):

D. J. van Wijk

Keyword(s):

Vulcanized Rubber ◽

Complete Survey ◽

Side Walls ◽

First Cause ◽

Made In ◽

Tear Resistance

Abstract By the resistance to tearing of a material is meant the resistance shown by the material, while under tension, to tearing completely apart after a split has been made in the surface by any means whatsoever. Without question, the destruction of rubber articles can in many cases be traced to tearing. The initial tears can be regarded as the result of a splitting of the inelastic oxidized skin or of injury to the surface. Tears on the side walls of a tire, for example, can be attributed to the first cause; the wear on the tread is attributable to the second cause mentioned above. Resistance to tearing should therefore be regarded as one of the most important properties of rubber. The numerous and widely different methods which have been proposed and used for determining resistance to tearing are proof of this. A complete survey of the literature to 1932 was published by Lefcaditis and Cotton. These authors described about twelve different methods for determining resistance to tearing, proposed a modified form of the method of Heidensohn, and determined the tear-resistance of various mixtures by this method. Subsequently, Lefcaditis studied this method further, and determined the effect of fillers and of mastication on resistance to tearing.

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