2016 11 1 nbsp 0183 32 6 1 Introduction Developments in the design fabrication and erection of steel structures together with the introduction of new high performance materials have lead to significant changes in the design buildability and performance of steel structures and in particular their connections 2020 11 17 nbsp 0183 32 It is noted that these hole sizes permit a reasonable tolerance for misalignment in setting the bolts and more precision in the adjustment of the base plate or column to the correct centerlines Note that these hole sizes are such that flame cutting will often be required An adequate washer see 7 2 4 should be provided for each anchor rod Slip Fits and GD amp T The gold standard for tolerancing GD amp T geometric dimensioning and tolerancing fully resolves these issues by calling out exactly the acceptable variation in all aspects of design geometry While they look like a complex symbolic language GD amp T callouts are well worth the time spent learning and a few basics will Under sized drill hole Hello I have an anchor installation with 1 3 8 quot bars that had 1 1 2 quot holes I could not find the hole diameter recommended for bars larger than 1 1 4 quot in the technical guide for larger diameter anchor rods I am assuming that the recommended hole would be 1 5 8 quot Placement Anchor bolts are required to be embedded in grout with the exception that 188 in 6 4 mm diameter anchors are permitted to be placed in mortar bed joints that are at least 189 in 12 7 mm thick Excluding anchors placed in mortar bed joints a minimum clearance of 188 in 6 4 mm and 189 in 12 7 mm is required between the anchor bolt and the nearest surface of masonry

2014 11 4 nbsp 0183 32 Hole Size and Bolt Spacing Hole Sizes SCM section J3 2 pg 16 1 105 defines hole sizes and types You need to review this section The vast majority of the time you will use standard holes which are 1 16 quot larger in diameter than the bolts that they hold However in special circumstances you may want to use oversized or slotted holes 2009 11 4 nbsp 0183 32 As stated above the 1 16 quot tolerance is for typical connections not base plates AISC states the proper size hole for anchor rods as small as 3 4 quot is 5 16 quot oversize It appears to me a 3 4 quot hole for a 1 2 quot anchor rod is not unreasonable DaveAtkins The tolerance for the location of anchor bolts is based on using oversized holes per the AISC Design Guide 1 Base Plates and Anchor Rod Design recommendations of the Structural Steel Educational Council and concrete contractor anchor bolt placement techniques Refer to the American Society of Concrete Contractor s Position Statement 14 2018 4 12 nbsp 0183 32 Since HSFG bolts under working loads do not rely on resistance from bearing holes larger than usual can be provided to ease erection and take care of lack of fit Typical hole types that can be used are standard extra large and short or long slotted These are shown in Fig 6 However the type of hole will govern the strength of the connection 2012 5 29 nbsp 0183 32 Anchor Fastening Technical Guide 1 0 Introduction 4 Hilti Inc US 1 800 879 8000 www us hilti com I en espa 241 ol 1 800 879 5000 I Hilti Canada Corp 1 800 363 4458 I www hilti ca I Anchor Fastening Technical Guide 2011 1 1 A bout Published Load Values The Anchor Fastening Technical Guide is intended to We passionately create enthusiastic

2020 11 17 nbsp 0183 32 The recommended maximum hole sizes for anchor rods in base plates are given in the AISC Steel Construction Manual Table 14 2 It is noted that these hole sizes permit a reasonable tolerance for misalignment in setting the bolts and more precision in the adjustment of the base plate or column to the correct centerlines 2020 2 17 nbsp 0183 32 4 Oversized holes in base plates help minimize tolerance problems 5 Bolting allows quick easy erection in any weather Disadvantages 1 Oversized base plates are usually thicker than column size base plates and thus are more expensive 2 Connection may not be concealed or pro tected from corrosion 3 When cast with concrete as one unit theRev 3 4 09 Screw Thread Design Screw Thread Fundamentals A screw thread is defined as a ridge of uniform section in the form of a helix on either the external or internal surface of a cylinder Internal threads refer to those on nuts and tapped holes while2004 5 13 nbsp 0183 32 Oversized holes are provided for erection tolerance to be able to fit the base plate over the cast in place anchor bolts which may not be placed exactly perfect in the field Shear may be transfered thru the anchor bolts if a plate washer with 1 16 quot oversized hole is field welded to the base plate at each anchor bolt For example a 13 16 in by 1 188 in slotted hole for a 190 in diameter bolt must be treated as a long slotted hole because it exceeds the maximum short slotted hole size 13 16 in by 1 in Note that the RCSC Specification in the footnote of Table 3 1 allows a 1 32 in tolerance on these maximum hole sizes as discussed in 2 4 2 and 2 5 5

ISO 4034 Hexagon nuts Grade C DIN 433 ISO 7092 Washers for use with cheese head screws DIN 433 1 ISO 7092 Product grade A washers with a hardness up to 250 HV designed for use with cheese head screws DIN 433 2 2021 10 3 nbsp 0183 32 1A anchor bolts with Class 1A threads 2A anchor bolts with Class 2A threads A When Grade 36 is specified a weldable Grade 55 may be furnished at the supplier s option 4 2 Weldable steel for Grade 55 is provided for in Supple mentary Requirement SI 5 Ordering Information 5 1 Orders for anchor bolts should include the following information 2014 8 22 nbsp 0183 32 Holes for anchor rods bolt diameter plus 1116 quot oversized holes bolt diameter plus 3116 quot and short and long slotted holes ment of anchorage devices has long been subject to more permissive tolerances and often inaccuracies that exceed those tolerances anyway and may require consideration by the structural Engineer 2018 9 27 nbsp 0183 32 7 Hole sizes in base plates may be up to 6 mm larger than the anchor bolt diameter AS 4100 Clause 14 3 5 2 Holes would normally be drilled Holes require a special plate washer of 6 mm minimum thickness under the nut if the bolt hole is more than 3 mm larger than the anchor bolt diameter The oversize holes will accommodate reasonable2021 4 7 nbsp 0183 32 bolts and nuts at the time of assembly the ASTM standards provide a clearance allowance for both bolt and nut threads to accommodate the size changes resulting from coating These coating allowances are provided in a table in each standard but only ASTM A563 provides the exact thread size limits when the allowances are added

2014 8 12 nbsp 0183 32 Specifying standard oversized holes for anchor rods Foundation inaccuracies are common Often the standard oversized hole dimensions used for bolts are not sufficient because there is not enough tolerance available Use AISC anchor rod and base plate hole recommendations Use the recommended hole sizes for base plates shown in AISC Design 2017 3 24 nbsp 0183 32 Reference drawing 8447253 Rev 4 A total of 246 anchor bolts were affected Six rupture restraints having 15 oversized anchor bolt holes were identified as being the typical cases and the amount of steel rods packed into the oversized holes was documented Details of this resolution are presented in Attachment 1 along with technical 2021 3 10 nbsp 0183 32 Based on AISC oversize holes the AISC Structural Steel Educational Council recommendations and concrete contractor anchor bolt placement techniques ASCC American Society of Concrete Contractors concrete contractors recommend the following tolerance for each bolt location 3 4 in and 7 8 in diameter bolts 177 1 4 in One of eight anchor holes in a concrete base for an equipment base install was drilled out of position by half diameter for 3 4 quot diameter anchors The installer attempted to correct the anchor hole position by redrilling oversizing the hole in the correct position We now have an oblong oval anchor placement hole oversized by an additional 3 8 quot 1 2 quot on one side When anchor bolt failure is such that complete replacement is necessary it can be accomplished using techniques consistent with the sketch shown in Figure 3 6 This sketch is of a typical replacement anchor bolt in an ideal installation Complete replacement of an anchor bolt is possible without lifting or regrouting the machine This is accomplished by drilling large