Guangzhou Steel News: Earthquake accounting point multilayered steel plant construction
When seismic checking, just ponder horizontal seismic effects and the construction of two spindles checking directions, respectively, in each direction horizontal seismic effects should all bear in this direction by the Seismic member. The effect of horizontal seismic base shear method may be used or modal response spectrum method of accounting. When accounting, in a multi earthquake, damping ratio can be 0.035; in rare earthquake, damping ratio may be 0.05.
Plant gravity load representative value and combination factors, in addition to compliance with the rules of Chapter 3, still comply with the following rules:
(1) floor maintenance load should not be less than 4kN / m2, load factor combined value of 0.4 is preferable;
(2) the accumulation of finished goods or material appearances load value according to the actual use, the load factor of the combined value of 0.8;
(3) Equipment and material inside the hopper full of the actual operating state adopted, when the material is fed intermittently, the combined value of the coefficient of material gravity load is taken as 0.8;
(4) inside the pipe material gravity load at actual operating state access, the combination of the value of coefficient of 1.0.
Direct support equipment components and their connections and the hopper, in addition to accounting dynamic vibration equipment load, there should be credited to the effect of gravity and seismic support member connected. Equipment for horizontal seismic effects and hopper support members and their connections can be determined as follows:
Fs = аmaxλGeq
λ = 1.0 + Hx / Hn
Where: Fs-- equipment or horizontal seismic effects at the standard value of the hopper center of gravity;
аmax-- maximum horizontal seismic influence coefficient;
Geq-- equipment or hoppers gravity load representative value;
λ-- amplification factor;
Hx-- base to the center of gravity away from the device or hopper;
From the bottom to the top of the building Hn-- basis of.
This horizontal seismic effects
Moment of the support member generated torque, take the device to a support member or hopper center of gravity away from the centroid accounting.
Multilayer steel structure plant load effect combinations according to the relevant rules of conduct Chapter 3.
Multilayer structure more regular layout, the accounting planar horizontal structure of the accounting model, when the plane was irregular and rigid floor slab, spatial calculation model; calculation of the vertical structure of the plant, according to column column method of accounting When the columns of different column longitudinal stiffness and rigidity when floor slab, with the overall accounting model space. There are pressure plate situ reinforced concrete floor, the board and connected with openings smaller shear studs, etc. When the member is connected with the beam, floor regarded as a rigid floor.
Earthquake effect effect accounting, accounted for using the inter-layer model, at the same time according to different envelope structure Consideration natural cycle reduction coefficient Ψ. When the light block and precast wall hanging, Ψ 0.9; when the heavy masonry outsourcing, Ψ 0.85; when the heavy masonry wall inlay puzzle when, Ψ take all enclosure wall only 0.8 meters the quality, do not think the stiffness and seismic work together. When constructing the plant and equipment or supporting devices to work together, when it accounted for horizontal seismic effects, it should be included in the stiffness of the device and its supporting structure, the seismic effect effect by device or support structure and plant construction equipment lateral stiffness of proportional distribution.
Horizontal structure of the multilayer structure is accounted for using the accounting machine accounting, when much of the structure of the layers of hand-count approach to effect its internal force under the effect of vertical load available approximation of hierarchical method of accounting, internal force effects under the effect of horizontal load approximation approach can be semi-rigid frame method, D value method of accounting.
Accounting displacement between layers, structure - support structure may not be counted shear deformation of beam-column joints domains, web thickness of not less than beams, columns and cross-sectional height of 1/70 Guangzhou Steel.