5-141 Nuts on anchor rods shall be brought in contact with the masonr y plate or sole plate as shown on the Plans. Threads on anchor rods shall be upset with a punch to prevent easy removal of the nuts. When anchor rods extend through slotted h oles in a sole plate, the lower of double nuts shall be l eft loose, bring to contact and loosen approximately ¼ turn, to allow movement of the sole plate. STEEL BEARINGS
523.10 Steel Bearings Structural steel bearings- rocker type and sliding plate type-
shall be fabricated in accordance with the dimensions and finis hes shown on the Plans, Standard Details and the requirements of Section 504, Structura l Steel. Bearings, base plates and other contact surfaces shall be finis hed to the following tolerances: Surface Roughness Requirements Steel slabs ANSI 2000 micro-inches Bearing sole plates ANSI 1000 micro-inches Milled ends to compression members, milled or ground ends of stiffeners or rockers ANSI 500 micro inches Bridge rockers and rollers ANSI 250 micro-inches Sliding bearings ANSI 125 micro-inches Pins and pin holes ANSI 125 micro-inches Bearing mating surfaces (includi ng steel to steel, or steel to bronze and steel to elastomeric material) shall have a minimum of 90% contact area. Flatness (the permissible variation from a true plane) shall be a maximum of 1/32 inch.
523.11 Materials Materials shall conform to Section 523.02, Ma terials.
ELASTOMERIC BEARINGS
523.20 Description Two types of bearings are applicable for th e following Sections:
Laminated Elastomeric Bearings, which shall consist of layers o f elastomer laminated to steel plates; and Plain Elastomeric Bearings, which shall consi st of a single layer of elastomer.
523.21 Materials Materials shall conform to Section 523.02, Ma terials.
If the elastomer material is specified by its shear modulus on the Plans, the measured shear modulus value shall lie within the specified range. When the elastomer material is specified by shear modulus, the Contractor shall supply a consi stent value of hardness for the purposes of defining limits for the tests of Table A and B in Section 711.11. Laminated Elastomeric bearings shall have a Shore A Durometer h ardness of 50 or 60. Plain Elastomeric bearings shall have a Shore A Durometer hardn ess of between 50 and 70.