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ICC-ES Evaluation Report Reissued October 2022
ESR-3912 This report is subject to renewal October 2023.
DIVISION: 03 00 00—CONCRETE
Section: 03 16 00—Concrete Anchors
DIVISION: 05 00 00—METALS
Section: 05 05 19—Post-installed Concrete Anchors
REPORT HOLDER:
DEWALT
EVALUATION SUBJECT:
MINI-UNDERCUT+™ ANCHORS IN CRACKED AND
UNCRACKED CONCRETE (DEWALT)
1.0 EVALUATION SCOPE
Compliance with the following codes:
2021, 2018, 2015 and 2012 International Building Code
®
(IBC)
2021, 2018, 2015 and 2012 International Residential
Code
®
(IRC)
For evaluation for compliance with codes adopted by Los
Angeles Department of Building and Safety (LADBS), see
ESR-3912 LABC and LARC Supplement.
Property evaluated:
Structural
2.0 USES
The DEWALT Mini-Undercut+ anchor is used to anchor
building components to the underside (i.e. formed surface)
of cracked and uncracked normal-weight concrete and
lightweight concrete having a specified compressive
strength, f
′
c
, of 2,500 psi to 8,500 psi (17.2 MPa to
58.6 MPa) to resist static, wind and seismic, tension and
shear loads. Use of anchors is limited to supporting non-
structural components.
The anchors may also be installed in the underside of
cracked and uncracked hollow-core concrete slabs having
a minimum specified compressive strength, f
′
c
, of 6,000 psi
(41.4 MPa). Use of anchors is limited to supporting
non-structural components.
The anchor is an alternative to cast-in-place anchors
described in Section 1901.3 of the 2021, 2018 and 2015
IBC, Sections 1908 and 1909 of the 2012 IBC. The anchors
may be used in structures regulated by the IRC, provided an
engineered design is submitted in accordance with IRC
Section R301.1.3.
3.0 DESCRIPTION
3.1 Mini-Undercut+ Anchors:
Mini-Undercut+ anchors are internally threaded
undercutting anchors which receive threaded steel inserts
such as threaded rods and bolts in
3
/
8
-inch (9.5 mm)
diameter.
Available nominal size is
3
/
8
-inch (9.5 mm). The anchors
are manufactured from carbon steel and comprised of an
undercutting sleeve and an internally threaded plow which
have a minimum 0.0002-inch (5 μm) zinc plating in
accordance with ASTM B633. The Mini-Undercut+ anchor
is illustrated in Figure 1.
The anchors must be installed in predrilled holes using a
stop drill bit and engaged with a setting tool using a
recommended hammer drill (equipment supplied by
DEWALT) as noted in Table B of this report. The anchor
expands into the sides of the predrilled hole and interlocks
with the base material during installation.
3.2 Steel Insert Elements:
Threaded steel insert elements must be threaded into the
Mini-Undercut+ anchors to form a connection. The material
properties of the steel bolts and threaded rods must comply
with minimum ASTM A36 or equivalent.
3.3 Concrete and Hollow-core Concrete Slabs:
Normal-weight and lightweight concrete must comply with
Sections 1903 and 1905 of the IBC. The minimum concrete
compressive strength at the time of anchor installation is
noted in Section 5.3 of this report. Hollow-core precast
concrete slabs must comply with the configuration and
dimensions as indicated in Figure 4.
4.0 DESIGN AND INSTALLATION
4.1 Strength Design:
4.1.1 General: Design strength of anchors complying with
the 2021 IBC, as well as Section R301.1.3 of the 2021 IRC
must be determined in accordance with ACI 318-19 Chapter
17 and this report.
Design strength of anchors complying with the 2018 and
2015 IBC, as well as Section R301.1.3 of the 2018 and 2015
IRC must be determined in accordance with ACI 318-14
Chapter 17 and this report.
Design strength of anchors complying with the 2012 IBC,
as well as Section R301.1.3 of the 2012 IRC, must be
determined in accordance with ACI 318-11 Appendix D and
this report.
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Design parameters provided in Tables 2 and 3 of this
report are based on the 2021 (ACI 318-19), 2018 and 2015
IBC (ACI 318-14) and the 2012 IBC (ACI 318-11) unless
noted otherwise in Section 4.1.1 through 4.1.11 of this
report.
The strength design of anchors must comply with ACI
318-19 17.5.1.2, ACI 318-14 17.3.1 or ACI 318-11 D.4.1, as
applicable, except as required in ACI 318-19 17.10, ACI
318-14 17.2.3 or ACI 318-11 D.3.3, as applicable. Strength
reduction factors,
φ
, as given in Tables 2 and 3 of this report,
must be used in lieu of ACI 318-19 17.5.3, ACI 318-14
17.3.3 or ACI 318-11 D.4.3, as applicable, for load
combinations calculated in accordance with Section 1605.1
of the 2021 IBC or Section 1605.2 of the 2018, 2015 and
2012 IBC, Section 5.3 of ACI 318 (-19 and -14), or Section
9.2 of ACI 318-11, as applicable. Strength reduction factors,
φ
, as given in Appendix C of ACI 318-11 shall not be used.
The value of f
′
c
used in the calculation must be limited to a
maximum of 8,000 psi (55.2 MPa), in accordance with ACI
318-19 17.3.1, ACI 318-14 17.2.7 or ACI 318-11 D.3.7, as
applicable.
4.1.2 Requirements for Static Steel Strength in
Tension, N
sa
: The nominal static steel strength in tension,
N
sa
, of a single anchor must be calculated in accordance
with ACI 318-19 17.6.1, ACI 318-14 17.4.1 or ACI 318-11
Section D.5.1, as applicable, for the threaded steel element,
N
sa,rod
, as illustrated in Table 5 of this report. The lesser of
φ
N
sa,rod
in Table 5 or
φ
N
sa
provided in Table 2 for the Mini-
Undercut+ anchor shall be used as the steel strength in
tension.
4.1.3 Requirements for Static Concrete Breakout
Strength in Tension N
cb
or N
cbg
: The nominal concrete
breakout strength of a single anchor or a group of anchors
in tension, N
cb
or N
cbg
, respectively, must be calculated in
accordance with ACI 318-19 17.6.2, ACI 318-14 17.4.2 or
ACI 318-11 D.5.2, as applicable, with modifications as
described in this section. The basic concrete breakout
strength of a single anchor in tension in cracked concrete,
N
b
, must be calculated according to ACI 318-19 17.6.2.2,
ACI 318-14 17.4.2.2 or ACI 318-11 D.5.2.2, as applicable,
using the values of h
ef
and k
cr
as given in Table 2 of this
report. The nominal concrete breakout strength in tension in
regions where analysis indicates no cracking in accordance
with ACI 318-19 17.6.2.5.1(a), ACI 318-14 17.4.2.6 or ACI
318-11 D.5.2.6, as applicable, must be calculated with the
value of k
uncr
as given in Table 2 of this report and with ψ
c,N
= 1.0.
4.1.4 Requirements for Static Pullout Strength in
Tension, N
pn
: The nominal pullout strength of a single
anchor or a group of anchors, in accordance with ACI
318-19 17.6.3, ACI 318-14 17.4.3 or ACI 318-11 D.5.3, as
applicable, in cracked and uncracked concrete, N
p,cr
and
N
p,uncr
, respectively, is given in Table 2. In lieu of ACI
318-19 17.6.3.3, ACI 318-14 17.4.3.6 or ACI 318-11
D.5.3.6, as applicable, Ψ
c,P
= 1.0 for all design cases. The
nominal pullout strength in cracked concrete may be
adjusted by calculation according to Eq-1:
N
p,f
c
'
=
N
p,cr
�
f
'
c
'
2,500
(lb, psi) (Eq-1)
N
p,f
c
'
=
N
p,cr
�
f
'
c
'
17.2
(N, MPa)
where f
′
c
is the specified concrete compressive strength.
For hollow-core concrete slabs, the value of 6,000 psi
(41.4 MPa) must be substituted for the value of 2,500 psi
(17.2 MPa) in the denominator.
Where value for N
p,uncr
is not provided in Table 2 of this
report, the pullout strength in tension need not be
considered or evaluated.
4.1.5 Requirements for Static Steel Shear Capacity,
V
sa
: The nominal static steel strength in shear, V
sa
, of a
single anchor must be taken as the threaded steel element
strength, V
sa,rod
, given in Table 5 of this report. The lesser of
φ
V
sa,rod
in Table 5 or
φ
V
sa
in Table 3 for the Mini-Undercut+
anchor shall be used as the steel strength in shear, and
must be used in lieu of the values derived by calculation
from ACI 318-19 Eq. 17.7.1.2a or 17.7.1.2b, ACI 318-14 Eq.
17.5.1.2a or 17.5.1.2b; or ACI 318-11 Eq. D-28 or D-29, as
applicable.
4.1.6 Requirements for Static Concrete Breakout
Strength in Shear, V
cb
or V
cbg
: The nominal concrete
breakout strength of a single anchor or group of anchors
in shear, V
cb
or V
cbg
, respectively, must be calculated in
accordance with ACI 318-19 17.7.2, ACI 318-14 17.5.2 or
ACI 318-11 D.6.2, as applicable, with modifications as
described in this section. The basic concrete breakout
strength of a single anchor in shear, V
b
, must be calculated
in accordance with ACI 318-19 17.7.2.2.1, ACI 318-14
17.5.2.2 or ACI 318-11 D.6.2.2, as applicable, using the
value of ℓ
e
and d
a
given in Table 3 of this report.
For anchors installed in hollow-core concrete slabs, the
nominal concrete breakout strength of a single anchor or
group of anchors in shear, V
cb
or V
cbg
, must be calculated
in accordance with ACI 318-19 17.7.2, ACI 318-14 17.5.2
or ACI 318-11 D.6.2, as applicable, using the actual
member cover thickness of the hollow-core, h
min,core
, in lieu
of h
min
, in the determination of A
vc
. Minimum member cover
thickness for anchors in the hollow-core concrete slabs is
given in Table 1 and shown in Figure 4 of this report, as
applicable.
4.1.7 Requirements for Static Concrete Pryout
Strength in Shear, V
cp
or V
cpg
: The nominal concrete
pryout strength of a single anchor or group of anchors, V
cp
or V
cpg
, respectively, must be calculated in accordance
with ACI 318-19 17.7.3, ACI 318-14 17.5.3 or ACI 318-11
D.6.3, as applicable, using the value of k
cp
provided in Table
3, and the value of N
cb
or N
cbg
as calculated in Section 4.1.3
of this report.
4.1.8 Requirements for Seismic Design:
4.1.8.1 General: For load combinations including seismic
loads, the design must be performed in accordance with ACI
318-19 17.10, ACI 318-14 17.2.3 or ACI 318-11 D.3.3, as
applicable. Modifications to ACI 318-19 17.10 or ACI
318-14 17.2.3 shall be applied under 2021, 2018 and 2015
IBC Section 1905.1.8, as applicable. For the 2012 IBC,
Section 1905.1.9 shall be omitted.
The nominal steel strength and nominal concrete breakout
strength for anchors in tension, and the nominal concrete
breakout strength and pryout strength for anchors in shear,
must be calculated according to ACI 318-19 17.6 and 17.7,
ACI 318-14 17.4 and 17.5 or ACI 318-11 D.5 and D.6,
respectively, as applicable, taking into account the
corresponding values in Tables 2 and 3 of this report.
The anchors comply with ACI 318 (-19 and -14) 2.3 or ACI
318-11 D.1, as applicable, as brittle steel elements and must
be designed in accordance with ACI 318-19 17.10.4,
17.10.5 or 17.10.6 and 17.10.7, ACI 318-14 17.2.3.4,
17.2.3.5, 17.2.3.6, and 17.2.3.7; ACI 318-11 D.3.3.4,
D.3.3.5, D.3.3.6 and D.3.3.7; or ACI 318-08 D.3.3.4, D.3.3.5
and D.3.3.6, as applicable.
The
3
/
8
-inch-diameter (9.5 mm) Mini-Undercut+ anchors
may be installed in regions designated as IBC Seismic
Design Categories A through F.
4.1.8.2 Seismic Tension: The nominal steel strength and
nominal concrete breakout strength for anchors in tension
must be calculated according to ACI 318-19 17.6.1 and
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17.6.2, ACI 318-14 17.4.1 and 17.4.2, or ACI 318-11 D.5.1
and D.5.2, as applicable, as described in Sections 4.1.2 and
4.1.3 of this report. In accordance with ACI 318-19
17.6.3.2.1, ACI 318-14 17.4.3.2 or ACI 318-11 D.5.3.2, as
applicable, the appropriate value for nominal pullout
strength in tension for seismic loads, N
p,eq
, described in
Table 2 of this report, must be used in lieu of N
p
. N
p,eq
, and
may be adjusted by calculations for concrete compressive
strength in accordance with Eq-1 of this report.
4.1.8.3 Seismic Shear: The nominal concrete breakout
strength and pryout strength for anchors in shear must be
calculated according to ACI 318-19 17.7.2 and 17.7.3, ACI
318-14 17.5.2 or 17.5.3, or ACI 318-11 D.6.2 and D.6.3,
respectively, as described in Sections 4.1.6 and 4.1.7 of this
report. In accordance with ACI 318-19 17.7.1.2, ACI 318-14
17.5.1.2 or ACI 318-11 D.6.1.2, as applicable, the
appropriate value for nominal steel strength in shear for
seismic loads, V
sa,eq
, described in Table 3 of this report,
must be used in lieu of V
sa
.
4.1.9 Requirements for the Interaction of Tensile and
Shear Forces: The effects of combined tensile and shear
forces must be determined in accordance with ACI 318-19
17.8, ACI 318-14 17.6 or ACI 318-11 D.7.
4.1.10 Requirements for Critical Edge Distance, c
ac
: In
applications where c < c
ac
and supplemental reinforcement
to control splitting of the concrete is not present, the
concrete breakout strength in tension for uncracked
concrete, calculated according to ACI 318-19 17.6.2, ACI
318-14 17.4.2 or ACI 318 D.5.2, as applicable, must be
further multiplied by the factor ψ
cp,N
as given by Eq 2:
ψ
cp,N
=
ac
c
c
(Eq-2)
whereby the factor ψ
cp,N
need not be taken less than
1.5h
ef
c
ac
.
For all other cases, ψ
cp,N
= 1.0. In lieu of using ACI 318-19
17.9.5, ACI 318-14 17.7.6 or ACI 318-11 D.8.6, as
applicable, values of c
ac
provided in Table 2 of this report
must be used, as applicable
4.1.11 R
equirements for Minimum Member Thickness,
Minimum Anchor Spacing and Minimum Edge Distance:
In lieu of ACI 318-19 17.9.2, ACI 318-14 17.7.1 and 17.7.3,
or ACI 318-11 D.8.1 and D.8.3, respectively, as applicable,
the values of s
min
and c
min
as given in Table 1 of this report
must be used. In lieu of ACI 318-19 17.9.4, ACI 318-14
17.7.5 or ACI 318-11 D.8.5, as applicable, minimum
member thicknesses, h
min
, as given in Table 1 of this report
must be used.
4.1.12 Lightweight Concrete: For the use of anchors in
lightweight concrete the modification factor λ
a
equal to 0.8λ
is applied to all values of
c
f
′
affecting N
n
and V
n
.
For ACI 318-19 (2021 IBC), ACI 318-14 (2018 and 2015
IBC), and ACI 318-11 (2012 IBC), λ shall be determined in
accordance with the corresponding version of ACI 318.
4.2 Allowable Stress Design (ASD):
4.2.1 General: Design values for use with allowable stress
design load combinations calculated in accordance with
Section 1605.1 of the 2021 IBC or Section 1605.3 of the
2018, 2015 and 2012 IBC must be established using the
following equations:
T
allowable,ASD
=
φ
N
n
/
α
(Eq-3)
V
allowable,ASD
=
φ
V
n
/
α
(Eq-4)
where:
T
allowable,ASD
= Allowable tension load (lbf or kN)
V
allowable,ASD
= Allowable shear load (lbf or kN)
φ
N
n
= Lowest design strength of an anchor or
anchor group in tension as determined in
accordance with ACI 318 (-19 and -14)
Chapter 17 and 2021, 2018 and 2015
IBC Section 1905.1.8, ACI 318-11
Appendix D, and Section 4.1 of this
report, as applicable. For the 2012 IBC,
Section 1905.1.9 shall be omitted.
φ
V
n
= Lowest design strength of an anchor or
anchor group in shear as determined in
accordance with ACI 318 (-19 and -14)
Chapter 17 and 2021, 2018 and 2015
IBC Section 1905.1.8, ACI 318-11
Appendix D, and Section 4.1 of this
report, as applicable. For the 2012 IBC,
Section 1905.1.9 shall be omitted.
α = Conversion factor calculated as a
weighted average of the load factors for
the controlling load combination. In
addition, α must include all applicable
factors to account for nonductile failure
modes and required over-strength.
Limits on edge distance, anchor spacing and member
thickness as given in Table 1 of this report must apply.
4.2.2 Interaction of Tensile and Shear Forces: The
interaction must be calculated and consistent with ACI
318-19 17.8, ACI 318-14 17.6 or ACI 318-11 D.7, as
applicable, as follows:
For shear loads V ≤ 0.2V
allowable,ASD
, the full allowable load
in tension T
allowable,ASD
must be permitted.
For tension loads T ≤ 0.2T
allowable,ASD
, the full allowable
load in shear V
allowable,ASD
must be permitted.
For all other cases:
T
allowable, ASD
+
V
allowable, ASD
≤ 1.2 (Eq-5)
4.3 Ins
tallation:
Installation parameters are provided in Table 1 and Figures
1A, 2, 3 and 4 of this report. Anchor locations must comply
with this report and plans and specifications approved by the
code official. The Mini-Undercut+ anchor must be installed
according to manufacturer’s printed installation instructions
and this report. Anchors must be installed in holes drilled
into concrete using carbide-tipped masonry drill bits
complying with ANSI B212.15-1994. The stop drill bit size
and drilled hole depth must be in accordance with Table 1.
The anchors must be installed in drilled holes with a
powered hammer drill and fitted with a Mini-Undercut+
setting tool supplied by DEWALT. The allowable ranges of
installation parameters for the Mini-Undercut+ anchors are
given in Table 1. The anchors must be driven until the
shoulder of the Mini-Undercut+ anchor is flush with the
surface of the concrete. The minimum thread engagement
of a threaded rod or bolt insert element assembly into the
Mini-Undercut+ anchor must be full anchor depth.
4.4 Special Inspection:
Periodic special inspection is required, in accordance with
Section 1705.1.1 and Table 1705.3 of the 2021, 2018, 2015
IBC or 2012 IBC, as applicable. The special inspector must
make periodic inspections during anchor installation to verify
anchor type, anchor dimensions, concrete type, concrete
compressive strength, hole dimensions, drill bit size and
type, anchor spacing, edge distances, concrete thickness,
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anchor embedment, and adherence to the installation
instructions. The special inspector must be present as often
as required in accordance with the “statement of special
inspection.”
5.0 CONDITIONS OF USE
The Mini-Undercut+ anchors described in this report comply
with, or are suitable alternatives to what is specified in, those
codes listed in Section 1.0 of this report, subject to the
following conditions:
5.1 The anchors must be installed in accordance with the
manufacturer's printed installation instructions and this
report. In case of conflict, this report governs.
5.2 Anchor sizes, dimensions and minimum embedment
depths are as set forth in this report.
5.3 The anchors must be limited to installation in the
formed surface of cracked and uncracked normal-
weight and lightweight concrete having a specified
compressive strength, f
′
c
, of 2,500 psi to 8,500 psi
(17.2 MPa to 58.6 MPa), and cracked and uncracked
hollow-core concrete slabs with the configuration and
dimensions as indicated in Figure 4 having a minimum
specified compressive strength, f
′
c
, of 6,000 psi
(41.4 MPa).
5.4 The values of f
′
c
used for calculation purposes must not
exceed 8,000 psi (55.1 MPa).
5.5 The concrete shall have attained its minimum design
strength prior to installation of the anchors.
5.6 Strength design values must be established in
accordance with Section 4.1 of this report.
5.7 Allowable stress design values must be established in
accordance with Section 4.2 of this report.
5.8 Anchor spacing and edge distance, as well as
minimum member thickness, must comply with Table
1 and Figures 2 and 4 of this report.
5.9 Prior to installation, calculations and details
demonstrating compliance with this report must be
submitted to the code official. The calculations and
details must be prepared by a registered design
professional where required by the statutes of the
jurisdiction in which the project is to be constructed.
5.10 Since an ICC-ES acceptance criteria for evaluating
data to determine the performance of anchors
subjected to fatigue or shock loading is unavailable at
this time, the use of these anchors under such
conditions is beyond the scope of this report.
5.11 Anchors may be installed in regions of concrete where
cracking has occurred or where analysis indicates
cracking may occur (f
t
> f
r
), subject to the conditions of
this report.
5.12 Anchors may be used to resist short-term loading due
to wind or seismic forces (Seismic Design Categories
A through F under the IBC), subject to the conditions
of this report.
5.13 Anchors are not permitted to support fire-resistance-
rated construction. Where not otherwise prohibited by
the code, anchors are permitted for installation in fire-
resistance-rated construction provided that at least one
of the following conditions is fulfilled:
• The anchors are used to resist wind or seismic forces
only.
• Anchors are used to support nonstructural elements.
5.14 Special inspection must be provided in accordance
with Section 4.4 of this report.
5.15 Use of anchors is limited to supporting non-structural
components.
5.16 Use of anchors is limited to dry, interior locations.
5.17 Anchors are manufactured under an approved quality-
control program with inspections by ICC-ES.
6.0 EVIDENCE SUBMITTED
6.1 Data in accordance with the ICC-ES Acceptance
Criteria for Mechnical Anchors in Concrete Elements
(AC193), dated October 2017 (Editorially revised
December 2020), which incorporates requirements in
ACI 355.2-19 / 355.2-07, for use in cracked and
uncracked concrete; including but not limited to
reference, reliability and service-condition tests in
cracked and uncracked concrete.
6.2 Reports of tension and shear tests of anchors in
hollow-core concrete slabs in accordance with
applicable sections as referenced in Section 6.1 of this
report.
6.3 Quality-control documentation in accordance with
the ICC-ES Acceptance Criteria for Quality
Documentation (AC10) dated January 2019.
7.0 IDENTIFICATION
7.1 The Mini-Undercut+ anchors have only one size and
one type, which is identified in the field by their unique
dimensional characteristics and packaging. Packages
are identified with the company name (DEWALT),
anchor name, part number, type, size, and the
evaluation report number (ESR-3912).
7.2 The report holder’s contact information is the following:
DEWALT
701 EAST JOPPA ROAD
TOWSON, MARYLAND 21286
(800) 524-3244
www.DEWALT.com
anchors@DEWALT.com
TABLE A—INSTALLATION AND DESIGN INDEX
1
Product Name
Installation
Specifications
Tension Design Data
Shear Design Data
Concrete
Hollow-core Concrete Slabs
Concrete
Hollow-core Concrete Slabs
Mini-Undercut+
Table 1
Table 2
Table 2
Table 3
Table 3
For SI: 1 inch = 25.4 mm. For pound-inch units: 1 mm = 0.03937 inch.
1
Reference ACI 318-19 17.5.2, ACI 318-14 17.3.1.1 or ACI 318-11 D.4.1.1, as applicable. The controlling strength is decisive from all appropriate failure modes
(i.e. steel, concrete breakout, pullout, pryout, as applicable) and design assumptions.
2
See Section 4.1.8 for requirements for seismic design, where applicable.
Concrete Type
Concrete State
Anchor Nominal Size
Seismic Design Categories
2
Normal-weight
Cracked
3
/
8
-inch A through F
Uncracked
3
/
8
-inch A and B
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TABLE B—MINI-UNDERCUT+ SYSTEM
SDS Stop Drill Bits Mini-Undercut+ Anchor SDS Setting Tool DEWALT Recommended SDS Hammer-Tools
PPA2431720
PFM2111820
PFM2101720
DCH273, DCH133, D25133, D25262, DCH263, D25263
1
1
Refer to Table 1 for requirements of approximate tool impact power.
FIGURE 1A—MINI- UNDERCUT+ ANCHOR DETAIL
Before (Left Picture) and After (Right Picture) Anchor Setting
FIGURE 1B—SDS STOP DRILL BIT (Top Picture),
MINI-UNDERCUT+ ANCHOR (Center Picture) AND
SETTING TOOL (Bottom Picture)
The DEWALT drilling systems shown below collect and remove dust with a HEPA dust extractor during the hole drilling operation in dry base
materials using hammer-drills.
FIGURE 1C—EXAMPLES DEWALT DUST REMOVAL DRILLING SYSTEMS WITH HEPA DUST EXTRACTORS FOR ILLUSTRATION
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TABLE 1—MINI-UNDERCUT+ ANCHOR INSTALLATION SPECIFICATIONS AND SUPPLEMENTAL INFORMATION
1,2,3
Anchor Property / Setting Information Symbol Units
Nominal Anchor Size / Threaded Rod Diameter (inch)
3
/
8
Nominal outside anchor diameter
d
a
in.
0.625
Internal thread diameter (UNC)
d
in.
3
/
8
Nominal stop drill bit diameter (ANSI)
d
bit
in.
5
/
8
Minimum nominal embedment depth
h
nom
in.
3
/
4
Effective embedment
h
ef
in.
0.75
Hole depth in base material
h
o
in.
3
/
4
Overall anchor length (prior to setting)
ℓ
anch
in.
15
/
16
Approximate tool impact power (hammer-drill)
-
J
2.1 to 3
Minimum concrete member thickness
h
min
in.
2
1
/
2
Minimum cover thickness in hollow core concrete slabs
(see Figure 4)
h
min,core
in. 1
1
/
2
Minimum edge distance
c
min
in.
2
1
/
2
Minimum spacing distance
s
min
in.
3
Minimum diameter of hole clearance in fixture for steel
insert element (following anchor installation)
d
h
in.
7
/
16
Approximate depth of internal thread
-
in.
13
/
32
Max. tightening torque for threaded steel insert element
(following anchor installation, as applicable; see Figure 2)
T
max
ft.-lb. 5
Effective tensile stress area (anchor body)
A
se
in.
2
0.044
Minimum specified ultimate strength
f
uta
psi
95,000
Minimum specified yield strength
f
ya
psi
76,000
Mean axial stiffness
4
Uncracked concrete
β
uncr
lbf/in.
50,400
Cracked concrete
β
cr
lbf/in.
29,120
For SI: 1 inch = 25.4 mm, 1 ft-lb = 1.356 N-m.
1
The information presented in this table is to be used in conjunction with the design criteria of ACI 318 (-19 or -14) Chapter 17 or ACI 318-11 Appendix D, as
applicable.
2
For installation detail for anchors in hollow-core concrete slabs, see Figure 4.
3
The embedment depth, h
nom
, is measured from the outside surface of the concrete member to the embedded end of the anchor, see Figure 1A.
4
Mean values shown, actual stiffness varies considerably depending on concrete strength, loading and geometry of application.
FIGURE 2—MINI-UNDERCUT+ ANCHOR INSTALLED WITH STEEL INSERT ELEMENT
1.) Using the
required stop drill
bit, drill a hole into
the base material
to the required
depth using the
shoulder of the
drill bit as a guide.
The tolerances of
the drill bit used
must meet the
requirements of
ANSI Standard
B212.15.
2.) Remove
dust and debris
from the hole
during drilling
(e.g. dust
extractor) or
following
drilling (e.g.
suction, forced
air) to extract
loose particles
created by
drilling.
3.) Attach the
required SDS
setting tool to the
hammer-drill.
Mount the open
end of the anchor
onto the setting
tool. Drive the
anchor into the
hole until the
shoulder of the
anchor is flush
with the base
material.
4.) Thread rod or bolt by hand until
full depth (snug tight) into the Mini-
Undercut+. Do not further tighten
threaded element with adjustable
wrench or similar tool. Do not exceed
the max. tightening torque.
FIGURE 3—MINI-UNDERCUT+ ANCHOR INSTALLATION INSTRUCTIONS IN THE UNDERSIDE FORMED SURFACE OF CONCRETE
ESR-3912
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FIGURE 4—MINI-UNDERCUT+ INSTALLATION DETAIL FOR ANCHORS IN THE UNDERSIDE OF HOLLOW-CORE CONCRETE SLABS
TABLE 2—TENSION DESIGN INFORMATION FOR MINI-UNDERCUT+ ANCHORS IN THE UNDERSIDE OF
CONCRETE AND THE UNDERSIDE OF HOLLOW CORE CONCRETE SLABS
1,2,3,4,5,6,7
Design Characteristic Notation Units
Nominal Anchor Size / Threaded Rod Diameter (in.)
3
/
8
inch
Anchor category
1, 2 or 3
-
1
Nominal embedment depth
h
nom
in.
3
/
4
Effective embedment
h
ef
in.
0.75
STEEL STRENGTH IN TENSION (ACI 318-19 17.6.1, ACI 318-14 17.4.1 or ACI 318-11 D.5.1)
Steel strength in tension
N
sa
lb
4,180
Reduction factor, steel strength
φ
-
0.65
CONCRETE BREAKOUT STRENGTH IN TENSION (ACI 318-19 17.6.2, ACI 318-14 17.4.2 or ACI 318-11 D.5.2)
Effectiveness factor for uncracked concrete
k
uncr
-
24
Effectiveness factor for cracked concrete
k
cr
-
17
Modification factor for cracked and uncracked concrete
Ψ
c,N
-
1.0 (see note 5)
Critical edge distance (uncracked concrete only) c
ac
in. 2.5
Reduction factor, concrete breakout strength
φ
-
0.40
PULLOUT STRENGTH IN TENSION (ACI 318-19 17.6.3, ACI 318-14 17.4.3 or ACI 318-11 D.5.3)
Pullout strength, uncracked concrete
N
p,uncr
lb
See note 7
Pullout strength, cracked concrete
N
p,cr
lb
455
Reduction factor, pullout strength
φ
-
0.40
PULLOUT STRENGTH IN TENSION FOR SEISMIC APPLICATIONS (ACI 318-19 17.10.3, ACI 318-14 17.2.3.3 or ACI 318-11 D.3.3.3)
8
Characteristic pullout strength, seismic
N
p,eq
lb
410
Reduction factor, pullout strength, seismic
φ
-
0.40
For SI: 1 inch = 25.4 mm, 1 ksi = 6.894 N/mm
2
; 1 lbf = 0.0044 kN.
1
The data in this table is intended to be used with the design provisions of ACI 318 (-19 or -14) Chapter 17 or ACI 318-11 Appendix D, as applicable; for anchors
resisting seismic load combinations the additional requirements of ACI 318-19 17.10, ACI 318-14 17.2.3 or ACI 318-11 D.3.3, as applicable, shall apply.
2
Installation must comply with manufacturer’s printed installation instructions and details.
3
All values of
φ
are applicable with the load combinations of 2021 IBC Section 1605.1 or 2018, 2015 and 2012 IBC Section 1605.2, ACI 318 (-19 or -14) Section
5.3, or ACI 318-11 Section 9.2. For concrete failure modes, no increase for ACI 318-19 17.5.3, ACI 318-14 17.3.3 Condition A or ACI 318-11 D.4.3 Condition A is
permitted.
4
The steel strength shown in this table is for the Mini-Undercut+ anchors only. Design professional is responsible for checking threaded rod strength in tension,
shear, and combined tension and shear, as applicable. See Table 5 for steel design information for threaded rod elements.
5
Select the appropriate effectiveness factor for cracked concrete (k
cr
) or uncracked concrete (k
uncr
) and use ψ
c,N
= 1.0.
6
For calculation of N
pn
see Section 4.1.4 of this report. For all design cases, ψ
c,P
= 1.0. The characteristic pullout strength for concrete compressive strengths greater
than 2,500 psi for anchors may be increased by multiplying the value in the table by (f’
c
/ 2,500)
0.5
for psi or (f’
c
/ 17.2)
0.5
. For hollow-core concrete slabs the
characteristic pullout strength for concrete compressive strengths greater than 6,000 psi for anchors may be increased by multiplying the value in the table by (f’
c
/
6,000)
0.5
for psi or (f’
c
/ 41.4)
0.5
.
7
Pullout strength does not control the design of indicated anchors. Do not calculate pullout strength for the indicated anchor size and embedment.
8
Reported values for characteristic pullout strength in tension for seismic applications are based on test results per ACI 355.2, Section 9.5 and must be used for
design.
ESR-3912
|
Most Widely Accepted and Trusted Page 8 of 10
TABLE 3—SHEAR DESIGN INFORMATION FOR MINI-UNDERCUT+ ANCHORS IN THE UNDERSIDE OF CONCRETE AND THE
UNDERSIDE OF HOLLOW CORE CONCRETE SLABS
1,2,3,4
Design Characteristic Notation Units
Nominal Anchor Size / Threaded Rod Diameter (in.)
3
/
8
inch
Anchor category
1, 2 or 3
-
1
Nominal embedment depth
h
nom
in.
3
/
4
Effective embedment
h
ef
in.
0.75
STEEL STRENGTH IN SHEAR (ACI 318-19 17.7.1, ACI 318-14 17.5.1 or ACI 318-11 D.6.1)
5
Steel strength in shear
V
sa
lb
985
Reduction factor, steel strength
φ
-
0.60
STEEL STRENGTH IN SHEAR FOR SEISMIC APPLICATIONS (ACI 318-19 17.10.3, ACI 318-14 17.2.3.3 or ACI 318-11 D.3.3.3)
6
Steel strength in shear, seismic
V
sa,eq
lb
895
Reduction factor, steel strength in shear, seismic
φ
-
0.60
CONCRETE BREAKOUT STRENGTH IN SHEAR (ACI 318-19 17.7.2, ACI 318-14 17.5.2 or ACI 318-11 D.6.2)
Load bearing length of anchor in shear
ℓ
e
in.
0.75
Nominal outside anchor diameter
d
a
in.
0.625
Reduction factor, concrete breakout strength
φ
-
0.45
PRYOUT STRENGTH IN SHEAR (ACI 318-19 17.7.3, ACI 318-14 17.5.3 or ACI 318-11 D.6.3)
Coefficient for pryout strength
k
cp
-
1.0
Reduction factor, pryout strength
φ
-
0.45
For SI: 1 inch = 25.4 mm, 1 lbf = 0.0044 kN.
1
The data in this table is intended to be used with the design provisions of ACI 318 (-19 or -14) Chapter 17 or ACI 318-11 Appendix D, as applicable; for anchors
resisting seismic load combinations the additional requirements of ACI 318-19 17.10, ACI 318-14 17.2.3 or ACI 318-11 D.3.3, as applicable shall apply
2
Installation must comply with manufacturer’s printed installation instructions and details.
3
All values of
φ
are applicable with the load combinations of IBC Section 1605.2, ACI 318 (-19 or -14) Section 5.3, or ACI 318-11 Section 9.2. For concrete failure modes,
no increase for ACI 318-19 17.5.3 supplementary reinforcement present, ACI 318-14 17.3.3 Condition A or ACI 318-11 D.4.3 Condition A is permitted.
4
The strength shown in this table is for the Mini-Undercut+ anchors only. Design professional is responsible for checking threaded rod strength in tension, shear, and
combined tension and shear, as applicable. See Table 5 for steel design information for threaded rod elements.
5
Reported values for steel strength in shear are based on test results per ACI 355.2, Section 9.4 (in cracked concrete) and must be used for design in lieu of the
calculated results using equation 17.7.1.2b in ACI 318-19, 17.5.1.2b in ACI 318-14 or D-29 in ACI 318-11 D.6.1.2.
6
Reported values for steel strength in shear for the Mini-Undercut+ anchors are for seismic applications and based on test results in accordance with ACI 355.2, Section
9.6 and must be used for design.
TABLE 4—SPECIFICATIONS AND PHYSICAL PROPERTIES OF COMMON CARBON STEEL THREADED ROD ELEMENTS
THREADED ROD SPECIFICATION UNITS
MIN. SPECIFIED
ULTIMATE
STRENGTH, f
uta
MIN. SPECIFIED
YIELD STRENGTH
0.2 PERCENT OFFSET, f
ya
f
uta
f
ya
ELONGATION
MINIMUM
PERCENT
REDUCTION
OF AREA
MIN. PERCENT
RELATED NUT
SPECIFICATION
3
Carbon
Steel
ASTM A36/A36M
1
and
F1554
2
Grade 36
psi 58,000 36,000 1.61 23 40 (50 for A36)
ASTM A194 /
A563 Grade A
For SI: 1 inch = 25.4 mm, 1 psi = 0.006897 MPa. For pound-inch units: 1 mm = 0.03937 inch, 1 MPa = 145.0 psi.
1
Standard Specification for Carbon Structural Steel.
2
Standard Specification for Anchor Bolts, Steel, 36, 55, and 105-ksi Yield Strength.
3
Where nuts are applicable, nuts of other grades and style having specified proof load stress greater than the specified grade and style are also suitable.
TABLE 5—STEEL DESIGN INFORMATION FOR THREADED ROD ELEMENTS USED WITH MINI-UNDERCUT+ ANCHORS
1,2,3,4
DESIGN INFORMATION SYMBOL UNITS
3
/
8
-inch
Threaded rod nominal outside diameter
d
rod
in. 0.375
Threaded rod effective cross-sectional area
A
se
in
2
0.078
Nominal tension strength of threaded rod as
governed by steel strength
ASTM A36 or
F1554,
Grade 36
N
sa,rod
lb 4,525
Nominal tension strength of threaded rod as
governed by steel strength, seismic
N
sa,rod,eq
lb 4,525
Nominal shear strength of threaded rod as
governed by steel strength
ASTM A36 or
F1554,
Grade 36
V
sa,rod
lb 2,695
Nominal shear strength of threaded rod as
governed by steel strength, seismic
V
sa,rod,eq
lb 1,900
For SI: 1 inch = 25.4 mm, 1 pound = 0.00445 kN, 1 in
2
= 645.2 mm
2
. For pound-inch unit: 1 mm = 0.03937 inches.
1
Values provided for steel element material types, or equivalent, based on minimum specified strengths; N
sa,rod
and V
sa,rod
calculated in accordance with equations 17.7.1.2a
and 17.7.1.2b in ACI 318-19, 17.5.1.2a and 17.5.1.2b in ACI 318-14 or D-28 and D-29 in ACI 318-11, respectively, as applicable. V
sa,rod,eq
must be taken as 0.7V
sa,rod
.
2
φ
N
sa
shall be the lower of the
φ
N
sa,rod
or
φ
N
sa
for static steel strength in tension; for seismic loading
φ
N
sa,eq
shall be the lower of the
φ
N
sa,rod,eq
or
φ
N
sa,eq
.
3
φ
V
sa
shall be the lower of the
φ
V
sa,rod
or
φ
V
sa,
for static steel strength in tension; for seismic loading
φ
V
sa,eq
shall be the lower of the
φ
V
sa,rod,eq
or
φ
V
sa,eq
.
4
Strength reduction factors shall be taken from ACI 318-19 17.5.3, ACI 318-14 17.3.3 or ACI 318-11 D.4.3, as applicable, for steel elements.
Strength reduction factors for
load combinations in accordance with ACI 318-19 and ACI 318-14 5.3 or ACI 318-11 9.2, as applicable, governed by steel strength of ductile steel elements shall be taken
as 0.75 for tension and 0.65 for shear. The value of
φ
applies when the load combinations of 2021 IBC Section 1605.1 or 2018, 2015 and 2012 Section 1605.2 of the IBC,
ACI 318 (-19 or -14) 5.3 or ACI 318-11 9.2, as applicable, are used in accordance with ACI 318-19 17.5.3, ACI 318-14 17.3.3 or ACI 318-11 D.4.3, as applicable.
ICC-ES Evaluation Reports are not to be construed as representing aesthetics or any other attributes not specifically addressed, nor are they to be construed
as an endorsement of the subject of the report or a recommendation for its use. There is no warranty by ICC Evaluation Service, LLC, express or implied, as
to any finding or other matter in this report, or as to any product covered by the report.
Copyright © 2022 ICC Evaluation Service, LLC. All rights reserved. Page 9 of 10
ICC-ES Evaluation Report
ESR-3912 LABC and LARC Supplement
Reissued October 2022
This report is subject to renewal October 2023.
www.icc-es.org | (800) 423-6587 | (562) 699-0543 A Subsidiary of the International Code Council
®
DIVISION: 03 00 00—CONCRETE
Section: 03 16 00—Concrete Anchors
DIVISION: 05 00 00—METALS
Section: 05 05 19—Post-installed Concrete Anchors
REPORT HOLDER:
DEWALT
EVALUATION SUBJECT:
MINI-UNDERCUT+™ ANCHORS IN CRACKED AND UNCRACKED CONCRETE (DEWALT)
1.0 REPORT PURPOSE AND SCOPE
Purpose:
The purpose of this evaluation report supplement is to indicate that DEWALT Mini-Undercut+™ anchors in cracked and
uncracked concrete, described in ICC-ES evaluation report ESR-3912, have also been evaluated for compliance with the
codes noted below as adopted by Los Angeles Department of Building and Safety (LADBS).
Applicable code editions:
2020 City of Los Angeles Building Code (LABC)
2020 City of Los Angeles Residential Code (LARC)
2.0 CONCLUSIONS
The DEWALT Mini-Undercut+™ anchors in cracked and uncracked concrete, described in Sections 2.0 through 7.0 of the
evaluation report ESR-3912, comply with LABC Chapter 19, and LARC, and are subject to the conditions of use described in
this supplement.
3.0 CONDITIONS OF USE
The DEWALT Mini-Undercut+™ anchors described in this evaluation report supplement must comply with all of the following
conditions:
All applicable sections in the evaluation report ESR-3912.
The design, installation, conditions of use and labeling of the anchors are in accordance with the 2018 International Building
Code® (IBC) provisions noted in the evaluation report ESR-3912.
The design, installation and inspection are in accordance with additional requirements of LABC Chapters 16 and 17, as
applicable.
Under the LARC, an engineered design in accordance with LARC Section R301.1.3 must be submitted.
The allowable and strength design values listed in the evaluation report and tables are for the connection of the anchors to
the concrete. The connection between the anchors and the connected members shall be checked for capacity (which may
govern).
This supplement expires concurrently with the evaluation report, reissued October 2022.
ICC-ES Evaluation Reports are not to be construed as representing aesthetics or any other attributes not specifically addressed, nor are they to be construed
as an endorsement of the subject of the report or a recommendation for its use. There is no warranty by ICC Evaluation Service, LLC, express or implied, as
to any finding or other matter in this report, or as to any product covered by the report.
Copyright © 2022 ICC Evaluation Service, LLC. All rights reserved. Page 10 of 10
ICC-ES Evaluation Report
ESR-3912 FBC Supplement
Reissued October 2022
This report is subject to renewal October 2023.
www.icc-es.org | (800) 423-6587 | (562) 699-0543 A Subsidiary of the International Code Council
®
DIVISION: 03 00 00—CONCRETE
Section: 03 16 00—Concrete Anchors
DIVISION: 05 00 00—METALS
Section: 05 05 19—Post-Installed Concrete Anchors
REPORT HOLDER:
DEWALT
EVALUATION SUBJECT:
MINI-UNDERCUT+™
ANCHORS IN CRACKED AND UNCRACKED CONCRETE (DEWALT)
1.0 REPORT PURPOSE AND SCOPE
Purpose:
The purpose of this evaluation report supplement is to indicate that the DEWALT Mini-Undercut+ anchor in cracked and
uncracked concrete, described in ICC-ES evaluation report ESR-3912, have also been evaluated for compliance with the
codes noted below.
Applicable code editions:
2020 Florida Building Code—Building
2020 Florida Building Code—Residential
2.0 CONCLUSIONS
The DEWALT Mini-Undercut+ anchor, described in Sections 2.0 through 7.0 of the evaluation report ESR-3912, comply with
the Florida Building Code—Building and the Florida Building Code—Residential, provided the design requirements are
determined in accordance with the Florida Building Code—Building or the Florida Building Code—Residential, as applicable.
The installation requirements noted in ICC-ES evaluation report ESR-3912 for the 2018 International Building Code
®
meet the
requirements of the Florida Building Code—Building or the Florida Building Code—Residential, as applicable.
Use of the DEWALT Mini-Undercut+ anchor has also been found to be in compliance with the High-Velocity Hurricane Zone
Provisions of the Florida Building Code—Building and the Florida Building Code—Residential with the following condition:
a) For connections subject to uplift, the connection must be designed for no less than 700 pounds (3114 N).
For products falling under Florida Rule 61G20-3, verification that the report holder’s quality assurance program is audited by
a quality-assurance entity approved by the Florida Building Commission for the type of inspections being conducted is the
responsibility of an approved validation entity (or the code official when the report holder does not possess an approval by the
Commission).
This supplement expires concurrently with the evaluation report, reissued October 2022.
