Report - PEER - University of California, Berkeley

Construction of floor slabs: Floor slabs shall be constructed to satisfy thefollowing:(1) Thickness of floor slabs shall be 80 mm or more and 1/40 or more of theeffective span in the direction of the shorter side,(2) Spacing between tension reinforcing bars at maximum bending momentshall be 200 mm or less in the direction of the shorter side and 300 mm or less inthe direction of the longer side, and also 3 times or less of he thickness of thefloor slabs.The above provisions (1) and (2) shall not apply if the vibration and deformation isexamined by structural calculation in the Ultimate Strength Calculation outlined inthe Building Standard Law Enforcement Order.Precast concrete slabs shall meet the following additional requirements:(1) Connections with surrounding beams shall be able to transfer the existingstress;(2) Where two or more members are used, those members shall be firmly tied toeach other. Provided, that this shall not apply in cases where structural safetyhas been confirmed through structural calculation or experimentation.The provisions (1) and (2) shall not apply if the vibration and deformation isexamined by structural calculation in the Ultimate Strength Calculation outlined inthe Building Standard Law Enforcement Order.Construction of girders: Girders shall be provided with longitudinalreinforcement at the top and bottom, and shall have stirrups at intervals not exceeding3/4 of the girder depth.Bearing walls: Bearing walls shall be constructed to satisfy the followings: (1)thickness shall be 120 mm or more; (2) periphery of an opening of bearing walls shallbe reinforced with reinforcing bars of diameter of 12 mm or more; (3) bearing wallsshall be provided with horizontal and vertical reinforcing bars of diameter of 9 mm ormore at an interval of 300 mm or less (450 mm or less in the case of doublereinforcement) unless the structural safety is confirmed by the structural calculationoutlined by the Minister of Construction. The interval may be extended up to 350 mm(500 mm in the case of double reinforcement) for single-story buildings; (4)connection with surrounding columns and beams shall be able to transfers the existingstress at the parts. Bearing walls of box frame construction shall meet the additionalfollowing requirements: (1) width of bearing walls shall be 450 mm or more; (2) edgeand corner of a bearing wall shall be reinforced by reinforcing bars of diameter of 12mm or more; (3) bearing walls shall be firmly tied at the top and the bottom to wallgirders (continuous foundation or foundation girders in the case of the bottom of abearing wall on the lowest floor) of width not less than the thickness of the bearingwall, and to transfer the existing stress at the connection.Thickness of concrete cover for embedded bars: The thickness of concretecover for embedded bars shall be 20 mm or more for walls other than bearing walls orfloor slabs, 30 mm or more for bearing walls, columns or beams, 40 mm or more forwalls, columns, floors or beams which come directory in contact with the soil as well522