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From version < 2.5 >
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51 51  (% style="text-align: justify;" %)
52 52  Although the modal analysis is the most accepted method all over the world (as well as in EC8), it has some disadvantages. Some of them are listed as follows:
53 53  
54 -* The results which are calculated using the SRSS summation rule are not simultaneous. For example for a bending moment in a point of the structure we can’t show the simultaneous normal force in the same point, because the summation is carried out from component to component separately. Consequence of the summation rule, other calculations (second order application, stability analysis) are not interpreted,
55 -* Mainly from the application of the statistical method, the graphical results weakly can be followed compare to the results of statical calculation,
56 -* In a lot of cases great number of vibration shapes should be calculated to reach reasonable results which require long calculation time.
54 +* the results which are calculated using the SRSS summation rule are not simultaneous. For example for a bending moment in a point of the structure we can’t show the simultaneous normal force in the same point, because the summation is carried out from component to component separately. Consequence of the summation rule, other calculations (second order application, stability analysis) are not interpreted,
55 +* mainly from the application of the statistical method, the graphical results weakly can be followed compare to the results of statical calculation,
56 +* in a lot of cases great number of vibration shapes should be calculated to reach reasonable results which require long calculation time.
57 57  
58 58  (% style="text-align: justify;" %)
59 59  Despite of all disadvantages of this method, we can expect most trustable results if the code requirements are fulfilled.
60 60  
61 61  (% id="HLateralforcemethod" %)
62 -== Lateral force method ==
62 +== Lateral force method (Equivalent static load method) ==
63 63  
64 -Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
64 +(% style="text-align: justify;" %)
65 +The lateral force method partly eliminates the disadvantages of the previous method with simplification in certain cases. The method postulates that the dis- placement response of the structure for ground motion can be described with one (or both x', y' directions) mode shape. While this means generally a simplification or approximation, this method is suitable for a part of the structure (EC8 prescribes the condition of application). In this method the mode shape of the structure is a linear deviation or it is equivalent to the calculated fundamental vibration shape. In the case of linear deviation or mode shape the period also can be calculated by approximate formula.
65 65  
67 +(% style="text-align: justify;" %)
68 +The application of this method gives possibility to transform the seismic lateral forces to simple static loads and it is applicable as follows:
69 +
70 +* these loads (seismic load cases) can be combined with other static loads,
71 +* second order and stability analysis can be performed,
72 +* it is also possible to use these loads for hand calculation, so the results can be checked easily.
73 +
74 +(% style="text-align: justify;" %)
75 +This method is usable in FEM-Design with two options if the code permits:
76 +
77 +* assumption of linear deviation shape when the period also can be defined by the user (Static, linear shape),
78 +* application of the calculated fundamental vibration shape as the deformed shape of the structure and its period (Static, mode shape).
79 +
66 66  == National codes ==
67 67  
82 +(((
83 +(% style="text-align: justify;" %)
84 +Remarks in application of national codes:
85 +
86 +* before releasing the current version of FEM-Design, only the Eurocode and Norwegian national code contained special description for seismic calculation. In the other codes FEM-Design supports only the general mo- dal analysis,
87 +* most of the countries did not prepare the National Application Document (NAD) for the universal Eurocode, so the program uses the general pres-cription.
88 +)))
89 +
90 +Supported national codes and methods:
91 +
92 +|(% style="width:184px" %)British |(% style="width:1689px" %)Modal analysis
93 +|(% style="width:184px" %)Code independent|(% style="width:1689px" %)Modal analysis
94 +|(% style="width:184px" %)Danish|(% style="width:1689px" %)Modal analysis
95 +|(% style="width:184px" %)Eurocode (NA: - )|EC8-2005 (No NAD, static method, modal analysis)
96 +|(% style="width:184px" %)Eurocode (NA: British )|(% style="width:1689px" %)EC8-2005 (No NAD, static method, modal analysis)
97 +|(% style="width:184px" %)Eurocode (NA: German )|(% style="width:1689px" %)EC8-2005 (No NAD, static method, modal analysis)
98 +|(% style="width:184px" %)Eurocode (NA: Italian )|(% style="width:1689px" %)EC8-2005 (No NAD, static method, modal analysis)
99 +|Finnish (B4:2001) |(% style="width:1689px" %)Modal analysis
100 +|Finnish (By50:2005)|(% style="width:1689px" %)Modal analysis
101 +|(% style="width:184px" %)German|(% style="width:1689px" %)Modal analysis
102 +|(% style="width:184px" %)Hungarian|(% style="width:1689px" %)Modal analysis
103 +|(% style="width:184px" %)Norwegian|(% style="width:1689px" %)(((
104 +(% style="margin-top:4.65pt; margin-right:53.25pt; margin-bottom:.0001pt; margin-left:28.0pt; text-align:justify; margin:0cm 0cm 0.0001pt" %)
105 +(% lang="EN-US" style="font-size: 11pt; font-family: ~"Calibri~", ~"sans-serif~"; font-size: 9pt; font-family: ~"Times New Roman~", ~"serif~"" %)^^NS3491^^(% lang="EN-US" style="font-size: 11pt; font-family: ~"Calibri~", ~"sans-serif~"; font-size: 9pt; font-family: ~"Times New Roman~", ~"serif~"; letter-spacing: -0.1pt" %)^^-^^(% lang="EN-US" style="font-size: 11pt; font-family: ~"Calibri~", ~"sans-serif~"; font-size: 9pt; font-family: ~"Times New Roman~", ~"serif~"" %)^^12 (static ^^(% lang="EN-US" style="font-size: 11pt; font-family: ~"Calibri~", ~"sans-serif~"; font-size: 9pt; font-family: ~"Times New Roman~", ~"serif~"; letter-spacing: -0.1pt; letter-spacing: -0.05pt" %)^^method^^(% lang="EN-US" style="font-size: 11pt; font-family: ~"Calibri~", ~"sans-serif~"; font-size: 9pt; font-family: ~"Times New Roman~", ~"serif~"" %)^^,^^(% lang="EN-US" style="font-size: 11pt; font-family: ~"Calibri~", ~"sans-serif~"; font-size: 9pt; font-family: ~"Times New Roman~", ~"serif~"; letter-spacing: -0.1pt; letter-spacing: -0.05pt; letter-spacing: -0.05pt" %)^^ moda^^(% lang="EN-US" style="font-size: 11pt; font-family: ~"Calibri~", ~"sans-serif~"; font-size: 9pt; font-family: ~"Times New Roman~", ~"serif~"" %)^^l ^^(% lang="EN-US" style="font-size: 11pt; font-family: ~"Calibri~", ~"sans-serif~"; font-size: 9pt; font-family: ~"Times New Roman~", ~"serif~"; letter-spacing: -0.1pt; letter-spacing: -0.05pt; letter-spacing: -0.05pt; letter-spacing: -0.05pt" %)^^analysis)^^
106 +)))
107 +|(% style="width:184px" %)Swedish|(% style="width:1689px" %)Modal analysis
108 +
109 +Norwegian code differs from Eurocode in a few places, so they are reviewed together and the differences are marked separately.
110 +
68 68  ----
69 69  
70 70  = 2. Input data =
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