The thesis Influence of installation conditions on load capacity of bonded anchors for primary construction elements presents market analysis of bonded anchors at slovenian construction sites. By using the on-line survey as the research tool, show detailed view on use and appearance of bonded anchors was obtained.. The most common products and dimensions of anchors among users were than, with standard procedures, tested on a load resistance. The testing procedure for tension tests that enables the analysis of the influence of installation conditions on bond strength of anchors, and was therefore used in the experimental part of the research, is described in detail in this chapter as well. It has been frequently observed that the contractors of various construction works often use diamond core bits to drill holes necessary for the installation of bonded anchors. This drilling technique is often not tested and as such, it is not mentioned in the ETA approvals as appropriate for many types of bonded anchors. The obtained experimental results show that the drilling technique significantly influences the results of the tests.
These results are of extreme importance to everybody who is involved in work with bonded anchors (i.e. design and consulting engineers, supervisors, clients, contractors and subcontractors, owners) since this data was so far lacking. The research results show that we have to be cautious when bonded anchors are used in diamond drilled holes, while they have no Technical Approval for this installation procedure. All of three tested products show significant bonded strength decrease when the anchors are installed in diamond drilled holes, compared to the values measured on anchors installed in hammer drilled holes. It can be expected that, based on the obtained results, all project stakeholders will have a higher level of awareness regarding the influence of the selection of drilling technique, if the anchors are not approved for this kind of installation. The conducted experimental work shows that the reduction of bond strength can achieve up to 70% for some products, if diamond drilling technique is employed instead of the hammer drilling.
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