Load and Spacing Tables

Notice: Unless otherwise noted, all load and design values presented herein are based on the provisions of ACI 349-97 or earlier. Design guidance based on ACI 318-05 and ACI 349-06 is being prepared and will appear here shortly. In the mean time you may wish to review the results of cracked concrete testing performed in accordance with ACI 355.2 as called for in the new codes.

The following load and spacing tables have been extracted from ICBO Evaluation Report 4133 as a quick reference. For the complete report see: ICBO Evaluation Report 4133.

TABLE NO. 1-ALLOWABLE LOADS FOR DRILLCO MAXI-BOLTS (Pounds)
ANCHOR DIAMETER (inches)
TENSION
SHEAR CASE 1
SHEAR CASE 2
1/4
1,600
830
1,060
3/8 
3,900
2,025
2,580
1/2
7,105
3,690
4,695
5/8
11,305
5,870
7,475
3 /4
16,710
8,680
11,045
1
30,315
15,750
20,040
1 1/4
50,015
25,980
33,065

NOTES:
1. Case 1 applicable for grouted plates. Case 2 applicable for plates in contact with concrete surface.
2. Use straight line interaction for combined tension and shear loading.
3. All load allowables are premised on the anchor's ability to develop 100 percent of the stud bolt's minimum ultimate capacity. Table No. II specifies combinations of concrete compressive strength, anchor embedment, center-to-center spacing and edge distance which will allow the anchor to develop its ultimate capacity.
4. The allowable loads noted in the above table may be assigned to each anchor in a multiple-anchor attachment. A single anchor used to anchor an attachment shall be designed for one half of the allowable loads noted.
 
 

TABLE NO. II-EMBEDMENT AND CENTER-TOCENTER SPACING REQUIREMENTS
FOR UP TO SIX MAXI-BOLTS IN A RECTANGULAR PATTERN

ANCHOR PART NO.
ANCHOR
STUD
DIAMETER
(Inches)
MAXIMUM
ATTACHMENT
THICKNESS
(Inches)
EMBEDMENT
(Inches)
3000 psi CONCRETE
4000 psi CONCRETE
5000 psi CONCRETE
Minimum
Center to
Center
Spacing
(Inches)
Minimum
Edge
Distance
(Inches)
Minimum
Center to
Center
Spacing
(Inches)
Minimum
Edge
Distance
(Inches)
Minimum
Center to
Center
Spacing
(Inches)
Minimum
Edge
Distance
(Inches)
MB-250-4 1/4-2
MB-250-4 1/4-2 3/4
1/4
1/4
1.50
1.00
2
2 3/4
*4.50
 6.00
4.50
4.50
*4.50
 5.00
4.25
4.25
*4.50
 4.50
4.00
4.00
MB-375-6-3 1/2
MB-375-6-4 1/2
3/8
3/8
2.50
1.50
3 1/2
4 1/2
*7.50
 9.00
6.75
6.75
*7.50
 7.50
6.25
6.25
*7.50
 6.50
6.00
6.00
MB-500-8 1/4-6
MB-500-11 1/4-8
MB-500-13 1/4-10
1/2
1/2
1/2
1.00
2.00
2.00
6
8
10
12.50
 8.50
 6.00
8.75
8.75
8.75
10.00
 7.00
4.50
8.25
8.25
8.25
9.00
6.00
4.00
7.75
7.75
7.75
MB-625-10-7 1/2
MB-625-13-9 1/2
MB-625-16-12
5/8
5/8
5/8
1.25
2.25
2.75
7 1/2
9 1/2
12
16.00
 11.50
 8.00
11.00
11.00
11.00
13.00
 9.50
 6.50
10.25
10.25
10.25
11.50
8.50
5.50
9.75
9.75
9.75
MB-750-13 1/2-9 1/4
MB-750-16 1/2-11 1/2
MB-750-18 1/2-13
3/4
3/4
3/4
2.75
3.50
4.00
9 1/4
11 1/2
13
18.50
 14.00
 12.00
13.00
13.00
13.00
15.00
 12.00
 10.00
12.25
12.25
12.25
13.50
10.50
8.50
11.75
11.75
11.75
MB-1000-16 1/2-12 1/2
MB-1000-22 1/2-16 1/2
MB-1000-26 1/2-20 1/2
1
1
1
2.00
3.50
3.50
12 1/2
16 1/2
20 1/2
24.50
 17.00
 12.00
17.50
17.50
17.50
20.00
14.50
 9.50
16.25
16.25
16.25
18.00
12.50
7.50
15.50
15.50
15.50
MB-1250-20-16
MB-1250-30-23
MB-1250-37-29 1/2
1 1/4
1 1/4
1 1/4
1.75
5.00
5.50
16
23
29 1/2
31.50
 19.50
 12.00
22.00
22.00
22.00
26.00
16.00
 8.50
20.50
20.50
20.50
23.00
14.00
 6.50
19.25
19.25
19.25

*Recommendation based on independent laboratory testing. All other embedment and center to center recommendations based on design by analysis provisions of ACI 349. Appendix B.

NOTES:
1. Maximum attachment thickness is based on torque tensioning of anchor. Any lesser attachment thickness may be used. Where the anchor is to be hydraulically tensioned, maximum attachment thicknesses will be reduced by one stud diameter.
2. Consideration of stress area reduction for limited concrete depth is not reflected in the above table. Minimum concrete depth = anchor embedment plus (center-to-center spacing/2).
3. Maxi-Bolt part numbers are specified as follows: MB-Diameter Series Number --- Overall Length-Sleeve Length (combined expansion sleeve and distance tube lengths).
4. Minimum edge distances quoted are for shear or combined tension and shear. For tension loading, edge distance may be reduced to 75 percent of given value.
5. Allowable values are limited to a maximum of six bolts in a two-row, three-column, or three-row, two-column arrangement. Allowable values may also be used for anchors placed in a single line and separated from other anchor lines by a minimum distance of two times the anchor embedment length.
6. In-place embedment length is determined by subtracting the over-all length (second number shown in Anchor Part No. column) from the exposed projection.
 
 

NOMINAL
ANCHOR SIZE
(Inches)
DRILL DIAMETER
MAXIMUM
(Inches)
MINIMUM HOLE
DEPTH, ANCHOR
EMBEDMENT
PLUS
UNDERCUTTING TOOL TENSIONING
TORQUE
(Ft.-Lbs.)
SETTING LOAD
50% Fy (Pounds)
TENSIONING
LOAD 81% FY
(Pounds)
Diameter A
(Inches)
Diameter B
(Inches)
Tolerance
(Inches)
1/4 0.530 1 inch 0.500 0.625 +.010
-.030
9-12 1,700 2,700
3/8 0.655 1 inch 0.625 0.750 +.010
-.030
40-44 4,100 6,600
1/2 0.778 1 inch 0.709 0.949 +.010
-.030
80-85 7,455 12,077
5/8 0.975 1 inch 0.905 1.176 +.010
-.030
185-190 11,865 19,221
3/4 1.172 1 1/2 inch 1.102 1.550 +.010
-.040
345-350 17,535 28,406
1 1.690 2 inches 1.625 2.275 +.010
-.050
645-650 31,815 51,540
1 1/4 2.065 2 inches 2.000 2.770 +.010
-.060
1,470-1,475 52,485 85,024
1/2 Heavy 0.845 1 inch 0.812 1.120 +.010
-.030
80-85 7,455 12,077

NOTES:
1. Undercutting tool diameter A is given for identification purposes only. No tolerance applies to this dimension.
2. Undercutting tool diameters A and B are noted in Figure No. 3