NBC 2015振型反应谱和考虑水平剪力

For structures that qualify for the Dynamic Analysis Procedure, there are two further sub methods defined in 4.1.8.12 [1], including a Linear Dynamic Analysis, with either a Modal Response Spectrum Method or the Numerical Integration Linear Time History Method, or a Nonlinear Dynamic Analysis. This article will focus on a Modal Response Spectrum Method (RSA) and the further base shear requirements defined in NBC 2015.

NBC 2015年水平剪变体

假设这里未详细介绍，同时计算反应谱方法（RSA），那么在计算建筑物底部楼板基础平面中的水平剪力时，可以按照如下方法进行计算：添加横向地震荷载。 第4.1.8.12 [1]条中的一系列操作步骤定义了不同的水平剪力变化方案，这些荷载类型最终可以调整楼层的剪力和内力，杆件力，如有必要，还可以挠度。

Step 1) In Sentence (5) [1], the elastic base shear, V_e, should be determined from a linear dynamic analysis, which is the first step in understanding the NBC base shear requirements. V_e对于反应谱不应包括任何附加系数或比例。

第2步）使用从定理（5） [1]中_确定的V e根据定理（6）[1]确定水平设计弹性剪切V_ed 。 For all structures located on sites other than Class F and having a seismic force-resisting system (SFRS) with a ductility-related force modification factor, R_d, equal to or greater than 1.5, then V_e should be multiplied by the larger of the following two factors:

步骤3）将预先确定的剪力V_ed乘以第4.1.8.5 [1]节中规定的重要性_{系数I e} ，并除以与延展性相关的力修正系数，_d R_o可以通过在表4.1.8.9 [1]中确定水平剪力V_{d来确定。}

第4步）按照简化的ESFP按照第4.1.8.11 [1]条的规定计算侧向地震设计力V。

NBC 2015横向剪力比例要求

考虑到上述信息，结合4.1.8.12（8） [1] ，V_d ，如果_{步骤3的V d}小于步骤4的V的80％，那么对于所有规则的，那些可以用ESFP设计的结构。

For all irregular structures which require a dynamic analysis specified in 4.1.8.7 [1], as well as wood structures greater than 4 stories which meet the criteria set forth in 4.1.8.12(12) [1], then V_d shall be taken as the larger of V_d or V stated in 4.1.8.12(9) [1].

In addition to these minimums, the scale factor V_d/V_e should be applied to story shears, story forces, member forces, and deflections, including the effects of accidental torsion to determine the design values from 4.1.8.12(10) [1].

NBC 2015横向剪切在RFEM中的应用

With the multiple variations for base shear discussed in NBC 2015, it may be difficult to determine which base shear variant is provided when running a response spectra analysis according to the standard in the structural analysis program RFEM.

Within the RF-DYNAM Pro - Equivalent Loads module, there are two spectrum types available after selecting NBC 2015, including the "Elastic response spectrum" and the "Design spectrum for linear calculation".

“弹性反应谱”提供了_{结构V e的}来自4.1.8.12（5） [1]或以上步骤1的弹性水平剪切。 该值不包括I_e/R_d R_o或其他因素的考虑。

• 3D Viewer | Google
• 3D Viewer | Babylon
• 虚拟现实

NBC 2015 模态反应谱分析的弹性反应谱类型

“线性分析的设计谱”提供了_{结构V d}从4.1.8.12（7） [1]或上面的步骤3的设计水平剪力。 但是要注意，在4.1.8.12（6）或上面的步骤2中指定的附加系数不包括在该计算中。 The calculation does include I_e/R_dR_o, as these variables are listed in the RF-DYNAM Pro - Equivalent Loads Code Parameters table, whereas they are not listed for the "Elastic response spectrum".

NBC 2015 模态反应谱分析的线性计算类型设计谱

用户可以对每种类型的频谱荷载比例进行缩放，以便在附加模块中考虑缩放系数的要求。 例如结构分析挠度所需的“弹性反应谱”，因为其中不包括_{I e}/R_d R_o的影响，必须_{像4.1中一样用V d}/V e缩放。_。需要8.12（10）。 For the "Design Spectrum for Linear Calculation" type, the V_d/V_e scale factor may also apply in addition to the factor specified in 4.1.8.12(6) or Step 2 above, which is not included in the calculation. RF-DYNAM Pro - Equivalent Loads provides a scaling option in each of global directions X, Y, and Z, in which the seismic force can be applied.

NBC 2015振型反应谱分析中RF-DYNAM Pro -等效荷载的缩放选项

In summary, the linear dynamic analysis requirement and in particular the modal response spectrum analysis set forth by NBC 2015 are possible to consider utilizing the FEA program RFEM in addition to the RF-DYNAM Pro - Equivalent Loads add-on module. 可以在程序中通过光谱的类型描述或使用在附加模块中输入的缩放系数来计算第4.1.8.12条中的许多水平剪变。

NBC 2015 RF-DYNAM Pro 中弹性反应谱类型的弹性基础剪力 Ve - 等效荷载