TY - JOUR AU - Gilford B. Estores, AU - Wyndell A. Almenor, AU - Charity Hope A. Gayatin, PY - 2019/01/22 Y2 - 2024/03/29 TI - REGRESSION MODELING OF BREAKOUT STRENGTH OF AN EXPANSION ANCHOR BOLT AS INFLUENCED BY CONCRETE AGGREGATES JF - GEOMATE Journal JA - INTERNATIONAL JOURNAL OF GEOMATE VL - 16 IS - 57 SE - Articles DO - UR - https://geomatejournal.com/geomate/article/view/2862 SP - 163-169 AB - <p>The frictional resistance of an expansion anchor bolt depends directly on the normal forces <br>generated by the anchor expansion mechanism around the anchorage zone of the concrete base material. <br>However, only the concrete aggregates around the anchorage zone have the direct shear contact with the anchor. <br>This study aims to develop a regression model that predicts the breakout strength of an expansion anchor in <br>plain concrete as influenced by the coarse aggregate size, coarse aggregate content, and fine aggregate content. <br>Crushed coarse aggregates of sizes 10mm, 12.5mm, 19mm, and 25mm were used. The coarse aggregate content <br>for each coarse aggregate size was 0.3452, 0.4046, 0.4462, and 0.4750, respectively. The fine aggregate content <br>for each coarse aggregate size was 0.4243, 0.3771, 0.3514, and 0.3341, respectively. A heavy duty type of an <br>expansion anchor bolt was used. There were five samples of base material specimens considered for each size <br>of coarse aggregate. Each specimen was tested first for its compressive strength to ensure that it will meet the <br>designed compressive strength and it will vary only at an acceptable deviation before the installation of the <br>expansion anchors. The installed anchor bolts were then tested for pull-out. Tests results showed that among <br>the parameters considered, coarse aggregate size is the most significant factor that could influence the breakout <br>strength of an expansion anchor and it is optimum at 19mm size. A polynomial regression model is <br>recommended to predict the concrete breakout strength of an expansion anchor bolt as influenced by the coarse <br>aggregate size.</p> ER -