by clicking the arrows at the side of the page, or by using the toolbar.
by clicking anywhere on the page.
by dragging the page around when zoomed in.
by clicking anywhere on the page when zoomed in.
web sites or send emails by clicking on hyperlinks.
Email this page to a friend
Search this issue
Index - jump to page or section
Archive - view past issues
Concrete In Australia : March 2013
32 Concrete in Australia Vol 39 No 1 FEATURE: ANCHORING & PRECAST failure rather than a concrete cone failure. e footed anchors of Series 6 were of varying embedment depth; 120 mm, 170 mm and 240 mm effective embedment depth. All anchors of Series 6 failed due to steel tensile failure of the anchor. Series 6 anchor tests are mentioned here for context of the series notation; however, the data was not used in the analysis presented in this paper and is part of an ongoing research program. Plate-type edge-lift anchor pull-out tests (154) were conducted at concrete compressive strengths and embedment lengths that would precipitate a concrete cone failure. e edge-lift anchors were 252 mm, 272 mm and 295 mm effective embedment depth, 16 mm plate, with a profile as shown in Figure 2. ey were cast in thin (150 mm) panels with varying reinforcement arrangements in the panels and around the anchors, described in more detail below. e test specimens were identified in a series of panels which were constructed with the same reinforcement provided in the panels. Series 1 test panels had no reinforcement in the panels (as seen in Figure 3(a)). Series 2 had N16 shear bars placed over the notch of the anchor and a centrally placed N16 perimeter bar which extended the length of the panel and was lapped at the corners of the panels (as seen in Figure 3(b)). Series 3 had no shear bar and had centrally placed SL82 mesh with centrally placed N16 perimeter bar. Series 4 had an N16 shear bar, centrally placed SL82 mesh and a centrally placed N16 perimeter bar. Series 5 had an N12 shear bar, centrally placed SL82 mesh and a centrally placed N16 perimeter bar. Details are summarised in Table 3 and shown in Figure 3. Normal strength concrete was used throughout all series of the tests; being 14 mm coarse aggregate, 0.6 water/cement ratio, and nominal grade 40 MPa design strength supplied by a commercial ready-mix company. e range of concrete compressive strengths at time of test was 10.1 MPa to 40 MPa, with an average of 21 MPa. Full concrete compressive data for all series is shown in Table 2. e preparation of the specimens for testing is shown in the Figure 3. Figure 3(b) shows a typical 2 m x 2 m x 150 mm thick panel formwork with N16 perimeter bar and 16 mm x 295 mm effective embedment depth plate edge lift anchors in the form. As can be seen, this panel had two test anchors which was the typical arrangement. If after testing one of the anchors it was observed that cracking had propagated, then the second anchor, whilst still tested, was excluded from the results presented in this analysis and paper. e anchors were loaded under load-control at a rate of 20 kN/min via a hydraulic jack with a load cell. e test data recorded for each specimen included load-displacement (of the anchor relative to a fixed point on the test panel or block) and Test Series N16Shear bar N12Shear bar Central SL82 mesh N16 Perimeter bar 1 Nil Nil Nil Nil 2 Yes Nil Nil Yes 3 Nil Nil Yes Yes 4 Yes Nil Yes Yes 5 Nil Yes Yes Yes 6 Nil (not applicable) Nil (not applicable) Yes Yes 7 Nil (not applicable) Nil (not applicable) Yes Yes Test Series fcm mimimum (MPa) fcm maximum (MPa) fcm average (MPa) 1 18 26 21 2 16 28 23 3 10.1 36 18 4 15 40 22 5 15 35 23 64 24 64 3 71 82 62 1 Table 3. Reinforcement configurations for test series. Figure 2. Reinforcement layout. Table 2. Concrete compressive data for test series. Perimeter bar Anchor Shear bar Central SL82 Mesh Anchor void