ASME STS-1:2006 pdf free download

ASME STS-1:2006 pdf free download.Steel Stacks.
4.10.1.2 Guy Wire Anchorage. Guy cables shall be attached to a fixed and stable structure or foundation often referred to as a dead man. Each set of guy wire anchors should be at the same relative elevation above ground.
4.10.1.3 Guy Wire Material. Guy wires shall be galvanized or protected from corrosion by other suitable mean.s such as plastic coating or using stainless steel cable strands. The fittings required in the assembly of guy wires shall be galvanized. See Table 4.10.1.3 for cable selection criteria and refer to para. 2.2.4 for more details.
4.10.1.4 Guy Wire Pretensloning/Site Tensioning. Guyed stacks move laterally due to wind. With adequate initial tension in the guys (pretensioning), this movement is reduced. The pretension force as well as the procedure for pretensioning shall be established by the designer. To avoid stretching of the cables during construction, which may alter the design condition, use of prestretched cable is recommended. In the case of hot stacks (over 4(WiF), the pretension is usually less so that the cable is more forgiving as the stack grows. However, the lateral deflection of the stack will increase due to this reduction in pretension. Consequently. the guyed stack must be analyzed in both hot and cold conditions. A turnbuckle or take-up, typically provided at the guy- wire-to-dead-man connection, allows adjustment to the cable to set the pretension. The effect of temperature causing differential thermal expansion in stack and guys shall be considered. The effect of ice on guys shall also be considered. Refer to ASCE 7, Section 10.0 for additional information. The breaking strength (B.S.) of the cables should be based on a minimum factor of safety of 3. The efficiency of the fittings shall also be considered. For detailed information, such as material, size, and strength, refer to the cable manufacturer.
4.10.1.5 Guy Wire Inspection and Maintenance. lhe guy wires should be inspected frequently. This may comprise visual inspection of the cable or electromagnetic measurement, which estimates the lost metal thickness. For inspection frequency refer to para. 9.4.1. The pretension of the cables should also be periodically checked and verified. It is recommended that the guy wires he lubricated and tension verified every five years.
4.10.2 Analysis of Guy Wire Stacks. After height and stability considerations, the guy wire levels as well as the number and angle of the guy wires shall be established by the designer. Analysis of a multilevel guy wire stack is very complex due to many variable support conditions. Therefore, timesaving computer modeling for structural analysis is essential. In computer modeling the following parameters must be considered:
(a) nonlinear cable effects
(b) wind/seismic loads in different directions
(c) thermal expansion of the stack
4.10.3 Guy Wire Attachment to Stack. Commercial rated capacity of the cable shall be used for design of guy wire attachment assembly, including the lug. The stack shell shall be reinforced at the attachment level, by using continuous ring and stifleners as needed.