Technical Manual

Inc.

p 238

Chapter 3

Hydraulically-Driven Push Piers

CHAPTER 3

HYDRAULICALLY-DRIVEN PUSH PIERS

Step 2 Positioning the Bracket

• The bracket is placed under the footing and

raised into position with the horizontal and

vertical bearing plates in full contact with the

concrete surfaces. The bracket is temporarily

held in place using wood cribbing

(Figure

3.10.c1)

. Alternatively, a bracket RAYser

™

available from Foundation Supportworks for the

more commonly used brackets. The bracket

RAYser consists simply of a U-shaped plate

with bottle jacks to position the bracket and

hold it snug against the concrete during the

initial pier installation process

(Figure 3.10.c2)

Note:

For the Model PP400 system without an

external sleeve, the starter tube with the friction

reduction collar needs to slide up through the

bottom of the bracket before setting the bracket

against the footing.

• FSI under-footing brackets do not require

mechanical anchorage to the concrete

foundation. The published capacities are based

on testing and analyses without anchors. There

are bolt holes that may be used to mount the

bracket to the concrete with expansion or

adhesive anchors, if needed to meet the project

specifications. It should be noted, however, that

the use of anchors to mount the under-footing

bracketmay cause concrete spalling and cracking

from the repeated loading and unloading process

during pier installation and lock-off. Additionally,

drilling the anchor holes could compromise the

integrity of steel reinforcement. If mounting of the

under-footing bracket with anchors is required,

FSI recommends anchoring the bracket after the

system has been locked off.

Step 3 Mounting the Drive Stand and

Hydraulic Drive Cylinder

• Slide the exterior sleeve over the starter tube and

insert the sleeve and starter together through

the bracket

(Figures 3.10.d1 and 3.10.d2)

. Care

must be taken that the sleeve and starter are

properly aligned and extend past both the top

and bottom plates of the bracket. The sleeve

and starter could also be placed after mounting

the drive stand to the bracket. Installers may find

it easier, however, to set the sleeve and starter

without being restricted by the drive stand legs.

Figure 3.10.c1

Temporary bracket support with wood cribbing

Figure 3.10.c2

Bracket RAYser

support system