Principles And Guidelines For Proper Fastening - Simpson PTP-27S Operator's Manual

prIncIples and GuIdelInes FOr prOper FastenInG

FASTENING INTO MASONRY MATERIALS:
Masonry materials suitable for fastening into include:
– Poured concrete
– Precast concrete
– Pre-stressed concrete
– Grout-filled concrete block
– Grouted joints
Fasteners are primarily held into masonry by a clamping of the concrete around
the fastener. Factors that influence a fastener driven into concrete include:
– Depth of penetration
– Compressive strength of concrete
– Fastener spacing and edge distance
– Fastener shank diameter
– Concrete aggregate
PROPER DEPTH OF PENETRATION:
Shank Penetration
Concrete Block & Joints
9-10 times shank Dia.
Concrete 2000–2500 psi
7-8 times shank Dia.
Concrete 2500–4000 psi
Precast or prestressed 5-6 times shank Dia.
concrete 4,000 psi
FASTENER EDGE DISTANCE ON CONCRETE:
Distance should be no closer than 3".
MINIMUM DISTANCE BETWEEN FASTENINGS:
.125" to .145" shank diameter fasteners – 3" spacing.
.172" to .187" diameter shank pin - 4" spacing.
.218" to .25" diamter shank pin - 6" spacing.
CONCRETE THICKNESS:
Concrete thickness must be at least three times the fastener penetration.
.145" Dia.
1"–1 ⁄ "
1
4
or 1 ⁄ "–1 ⁄ "
1 1
4 2
or 1"–1 ⁄ "
1
4
or ⁄ "–1 ⁄ "
7 1
8 4
-9-
prIncIples and GuIdelInes FOr prOper FastenInG
FISH-HOOKING:
"Fish-hooking" is when the fastener curves when driven into concrete, due to the
fastener hitting large, hard, or excessive amounts of aggregate, rebar or any hard
object. Fish-hooking can reduce the holding power of the fastener, result in spalling,
and may increase unsafe conditions due to escaping particles. Fish-hooking can be
minimized by:
– Reducing shank penetration
– Increasing shank diameter
– Using appropriate powder load level. Excessive power can cause over driving.
– Fastening through a metal disc
FASTENING INTO STEEL:
The most common type of steel fastened into is structural steel in the form of beam,
angle iron, channel, tee, plate and strip. The holding power of the powder-actuated
fastener is a function of the gripping action of the steel base material around the
fastener and the fusion of the fastener to the base material.
FACTORS THAT INFLUENCE THE HOLDING POWER
OF FASTENERS IN STEEL ARE:
– Shank diameter: Larger shank diameters increase holding power
– Thickness of steel base material: Thicker base material increases holding power
– Fastener point penetration: Getting the point to pass through base material by
approximately " maximizes holding power
⁄
1
4
– Knurled fasteners: Knurling on the fastener provides interlocking of the shank
and the base material that increases the holding power
GENERAL RULES:
Minimum spacing of fasteners into steel is 1
fasteners into steel is ". Steel thickness must be no less than the shank
⁄
1
2
diameter of the fastener.
-10-
". Minimum edge distance of
⁄
1
2