Technical Specifications — Drop-in Anchors
There are numerous technical specifications that must be considered when using Concrete Drop-in Anchors. Considerations include: Drop-in Anchor diameter and material type, internal thread length, minimum edge distance and required hole size. The Concrete Drop-in Anchor is a great fastener option when working with flush mounting applications. The size of the Drop-in Anchor refers to the diameter of the standard UNC threaded rod or bolt to be used with this fastener. Once all these factors have been determined, you can find the expected holding values in the technical information below.
Drop-in Anchor Bolt Length:
When the drop-in anchor is set flush with the base material: To determine the minimum bolt length required, add the internal thread length of the drop-in anchor, plus the thickness of the material to be fastened, plus the thickness of any washer to be used.
When the drop-in anchor is set deeper into the concrete:
Determine the minimum bolt length above and add the additional depth to the minimum anchor length.
Drop-in Anchor Spacing:
The forces on a Drop-in Anchor are transferred to the material in which it is installed. If the anchors are installed too close together, it can cause an interaction of the forces, thus reducing the holding power of the anchor. Minimum anchor spacing and minimum edge distances for the drop-in anchor are as follows:
| 1/4" |
3-1/2" |
1-3/4" |
| 3/8" |
5-11/16" |
2-13/16" |
| 1/2" |
7" |
3-1/2" |
| 5/8" |
8-5/16" |
4-1/8" |
| 3/4" |
10-1/2" |
5-1/4" |
When vibration or sudden impact are part of the load conditions, the spacing should be increased.
Drop-in Anchor Ultimate Holding Values**
| 1/4 |
3/8 |
1 |
5 |
939 |
2067 |
| 3/8 |
1/2 |
1-9/16 |
10 |
1560 |
3995 |
| 1/2 |
5/8 |
2 |
20 |
3105 |
4110 |
| 5/8 |
7/8 |
2-1/2 |
40 |
3323 |
5750 |
| 3/4 |
1 |
3-1/8 |
80 |
6678 |
10807 |
** Values shown are average ultimate values and are offered only as a guide and are not guaranteed. A
safety factor of 4:1 or 25% is generally accepted as a safe working load. Reference should be made to
applicable codes for the specific working ratio. All values are based on close-tolerance holes drilled with carbide tipped drill bits. Designated holding power depends on the quality of the masonry material, depth of embedment, and proper hole size.
| DI14 |
DIS14 |
100/1000 |
1/4 |
1 |
1/2 |
3-1/2 |
1-3/4 |
| DI38 |
DIS38 |
50/1000 |
3/8 |
1-9/16 |
5/8 |
5-11/16 |
2-13/16 |
| DI12 |
DIS12 |
50/500 |
1/2 |
2 |
3/4 |
7 |
3-1/2 |
| DI58 |
DIS58 |
25/200 |
5/8 |
2-1/2 |
1 7/8 |
8-5/16 |
4-1/8 |
| DI34 |
DIS34 |
25/150 |
3/4 |
3-1/8 |
1-1/4 |
10-1/2 |
5-1/4 |