TILT-UP CONSTRUCTION - Brock White

Panel ErectionInformationComputer ServicePanel ErectionInformationFig. 1Fig. 2ANGLE @ 0 o ROTATIONA ≈ 60 oFig. 3B ≈ 90 oC ≈ 60 oANGLE @ 30 o ROTATIONA ≈ 30 oB ≈ 60 oC ≈ 90 o50 o20 o zontal) to approximately 90° (vertical).• All panels with openings are entered in the computerfor analysis.• Inserts are then positioned relative to the center ofgravity.• Panel dimensions and insert locations are checkedby the computer for exact insert loading and flexuralstress analysis.• The bending moments and stresses in a panel areconstantly changing as the panel rotates from 0° (hori-• Stresses are checked at various degrees of rotationwith respect to the horizontal.• The most critical stress during lifting will normally occursomewhere between 20° and 50° rotation. The reasonfor this range is the different geometric shapes of thepanels and number of inserts required.• The calculations for determining the stresses atvarying angles of rotation are extremely complex dueto the cable geometry and the method of structuralanalysis required, and can only be accomplishedefficiently by utilizing the accuracy and speed of thecomputer.• As the cable, attached to the lifting plate, changes itsangle during rotation, the force components on thelifting plate will vary causing the tension load on theinsert to vary.• When one insert's tension load increases, anotherinsert's tension load may decrease. This is whatcauses the bending moments and stresses to varythroughout rotation of the panel.• For example: the tension load at "B" in Fig. 3 is 100%tension and the tension load at "C" is 85% tension, butwhen rotated to 30° in Fig. 4, the tension load at "B"has decreased to 80% and the tension load at "C" hasincreased to 100%.• To provide uniformity in panel detailing, DaytonSuperior provides computerized or computer aideddrafting graphics in addition to the stress analysis.A B CA B C30 oFig.416 02-09