The “pull-out” test is quite often used as a simple method of estimating the material parameters of concrete or rock without the need for laboratory test. The test consists of pulling out the anchor placed in the material. On the basis of the test results, tensile strength and fracture energy can be estimated. Most often, this test is performed for concrete with an anchor, which was embedded during the formation of the sample ( Brencich, 2015 ; Wang, Wu, Ouyang, He, & Sun, 2017 ; Contrafatto & Cosenza, 2014 ). Thus, the characteristics of the
Experimental research of interaction between prestressing units coated with corrosion protection agents and surrounding material has been performed. This paper shows the result from pull-out tests of strands coated with emulsifiable oil and thixotropic compound. Primary goal is to compare bond stress behaviour at different types of specimens with strand coated or not coated with corrosion protection.
The aim of this study was to understand the stick-slip properties of dry polyester plain, ribs and satin woven fabric weaves. It was found that the amount of stick-slip force was related to the number of interlacement points in the fabric, whereas the amount of accumulative retraction force was related to fabric structural response. Stick-slip force and accumulative retraction force depend on fabric weave, fabric density, the number of pulled ends in the fabric and fabric sample dimensions. The weft directional single and multiple yarn stick-slip and accumulative retraction forces of dry plain fabrics in fabric edge and centre regions were higher than those in the satin fabric due to fabric weave. In addition, the warp directional single and multiple yarn stick-slip and accumulative retraction forces in the meso-cell-1 to the meso-cell-6 of dry wide and long satin fabric in fabric edge were higher than those in the weft direction due to fabric density. Stick-slip and accumulative retraction forces of polyester fabric in the multiple yarn pull-out test were higher than those of the single yarn pull-out test.
To begin with, the intorduction of this paper summarises literature sources that wrongly interpret results of the bond strength between hot-dip galvanised reinforcements and concrete. The influence of the total reinforcement anchorage length on the bond strength results assessment was studied in detail. The numeric analysis of beam models with various testing anchorage lengths (the analysis input data comprised the results of previous bond strength tests carried out in a laboratory) unambiguously confirmed that when the bond strength between concrete and hot-dip galvanised reinforcement with a sufficient test anchorage length is tested in a beam test, the negative impact of the coating corrosion on bond strength with concrete may be biased. It is more objective to test bond strength with concrete in a pull-out test where a very short test reinforcement anchorage length is set out as a standard.
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