|Cracked Concrete Head
|Always inspect materials when received from supplier. Do not install a head that
has a structural crack or fissure running internally into it. Slight flaking or
chipping does not constitute a crack.
|During installation, pins rubbing against the concrete head may cause superficial
flaking of concrete around the driving hole. This will not affect the structural
strength. However, if a structural crack or fissure running internally into the
concrete head develops during installation, the integrity of the pier has been
compromised and the concrete head must be removed and replaced.
|Concrete Head Will Not Stay Level When Installing
|One or more pins may be driving out of line due to obstructions in the soil (See
“Encountering Obstructions,” page 13), or your hole for setting the concrete
head may be too big. Only dig a hole the size of the head being used, and be
sure to put all pins in the head before setting them. With all the pins sticking up
from the head, one person can also push or pull on the pins to manipulate the
leveling process and guide or steer the concrete head to a level position, being
careful not to wrench on it and cause a crack.
|Concrete Head Installed Out of Level
|If a concrete head is more than 5 degrees out of level, the symmetry of the
bearing pins may be compromised—the head should be removed and
repositioned. Reinstall the pins incrementally at first, checking level constantly,
and if one pin is not going in straight and is causing the head to tip, install the
other pins first and then carefully finish driving this last pin.
|Hitting an Obstruction When Installing
|If an obstruction is encountered, the pins may be removed and the concrete
head repositioned. If the obstruction is dug out and removed, soil must be
recompacted per the Installation Instructions. See “Encountering Obstructions”.
|Installing in Frozen Ground
|Check with the local building code for criteria or limitations on installing foundations
in frozen soil. See “Frost Heave” and “Heave Resistance”.
|Pins Have Risen Slightly Out of the Concrete Head
|This may occur when extreme loads have been applied to the pier, but the
foundation is designed to relieve pressure in this way. The pins may simply be
tapped back to their original position with a small hammer. Remove the caps,
tap the pin, and replace the caps.
|Pins Will Not Fit into Concrete Head
|Make sure the pins fit into the concrete head before inserting the inspection
plugs. Be sure pins and concrete heads are free of dirt, and check both ends of
pins for fit. Always transport and store parts in a clean environment. Measure
the pin diameter to be sure the proper pins have been supplied for your pier
model. (The DP-50 model has a 1" nominal pin with a 1.315" actual outside
diameter [OD]; DP-75 has a 1-1/4" nominal pin with a 1.67" actual OD.) If the
pins still do not fit, contact your supplier.
|Pin Caps Will Not Fit over Driven Pins
|Check to be sure the proper cap size was supplied and that your caps are
pliable and not frozen. Caps should be tapped on with a small hammer. If they
still will not go on, check the pin ends for any extreme deformations that may
have occurred while driving. File or grind off any damage to re-establish the
original diameter, and apply the cap.