E2MDOFBuildingResponse

[jia]

Hello, I have some questions about example 2 (E2MDOFBuildingResponse), thank you!
The first is how do I see which seismic design level each building is matched to? It is High-Code, Moderate-Code, Low-Code, or Pre-Code.
Second, how can I see the damage directly? Is it slight, moderate, extensive or complete? Or do I need to match according to the data in Hazus?
Third, in the result file EDP_18-435.csv, does PID refer to interlayer displacement? If so, why video 【 SimCenter | Performance -based Engineering (PBE) Tool Training - Day 2, June 23, 2020] said it has no unit?

Thank you, best wishes to you!

[adamzs]

Hi Jia,

Example 2 uses the MDOF_LU tool to generate an idealized finite element model for each building and obtain the peak floor acceleration (PFA) and peak interstory drift ratio (PID) at each floor. The tool was developed by Prof. Xinzheng Lu's research group.

The capabilities are described to some extent in the appendix of this publication: http://dx.doi.org/10.1016/j.advengsoft.2014.01.010 .

You can also take a look at the source code here: https://github.com/NHERI-SimCenter/SimCenterBackendApplications/tree/master/modules/createSAM/MDOF-LU
Most assumptions are coded into the Building.cpp and HazusSAM_Generator.cpp files.

Now, to answer your specific questions:

1, Take a look at the CalcBldgPara function in HazusSAM_Generator.cpp. The four code levels are enumerated as integers ranging from 0 to 3 and you'll see how the Zone, Year of Construction, and Structure Type are used to obtain the design level. The developers aimed to implement the logic presented in the Hazus Earthquake Model; please let us know if you experience any errors in their implementation.

2, The damage is stored in the DM_*.csv file (where * is replaced by the range of building IDs). Example 2 uses the fragility functions from the Hazus Earthquake Model to simulate damages; this yields Damage States ranging from 0 to 4. 0 corresponds to no damage, while 1-2-3-4 corresponds to slight, moderate, extensive, and complete, just like you described in your question. Damage state 4 has two mutually exclusive sub-states (see some clarification on this in the end*), complete damage and collapse. Following the Hazus methodology, complete damage does not yield injuries, while collapse results in injuries and fatalities. Complete damage is encoded as DS 4_1, while collapse is encoded as DS 4_2.
You shall see the likelihood of observing each damage state in the structural and non-structural components of each building. If you are looking for each damage realization, you'll need to check the "Output EDP, DM, DV, every sampling realization" in the General Information (GI) panel of R2D (see here: https://nheri-simcenter.github.io/R2D-Documentation/common/user_manual/usage/desktop/R2DTool/GI.html). Afterward, you'll see a realizations.hdf5 file among the results that provides a specific damage state for each realization for each building. Let me know if you need more information on how to extract the information from this file.

3, PID in the EDP file refers to Peak Interstory Drift Ratio. As far as I can tell, this is in line with the PBE tool training video and has no unit.

Let me know if you have further questions.

Adam


* Additional information on mutually exclusive damage states:
Currently, R2D uses Pelicun 2.6 to simulate damage and loss. This earlier version of Pelicun followed the FEMA P-58 naming convention and assigned Damage State Groups (DSG) to fragility functions and each DSG could have one or more Damage States in it. This led to the DS_X_Y type of identification where X refers to the DSG and Y refers to the DS.
For the sake of clarity, with Pelicun 3, I updated this naming convention using Limit States instead of DSG. So, the results of an analysis performed by Pelicun 3 will show LS_X to identify the limit states or DS_Y to identify the damage states. I wanted to mention this detail here because Pelicun 3 will be available in R2D this April and it will completely replace Pelicun 2.6 in the near future.

[jia]

Thank you for your reply.
May I ask where can I find the principle formula based on DL module and Hazus MH EQ to calculate the damage state in R2D? Chapter 5 of Hazus Earthquake Model Technical Manual only introduces the method to determine the damage state according to PGA and PGD, but does not use the calculated PID and PFA.

And if I want to input the same ground motion for all buildings to verify the seismic capability of all types of buildings, and still use MDOF_LU and Hazus MH EQ modules, how to fill in the HTA module in R2D?
If the Number of samples and Number of neighbors are both 1, an error message is displayed. So I take 6 observation points, and the ground motion records of each observation point are the same. Is this reasonable? It works, but the earthquake resistance of the different types of results in the results is not realistic.

Thank you very much！

[adamzs]

Hi Jia,

Hazus MH EQ uses capacity curves to calculate a characteristic drift and acceleration for a building. The capacity curve method is explained in section 5.4.1. Example 2 in R2D uses the MDOF_LU model instead of the capacity curve method to obtain peak roof drift and peak roof acceleration for each building in a portfolio. Then, these values are used as demands for fragility functions based on section 5.4.2 of the Hazus MH EQ manual. Note that structural and drift-sensitive nonstructural fragilities use drift ratio as demand and acceleration-sensitive nonstructural fragilities use acceleration as demand. See, for example, columns 4-7 in Table 5-12 for structural fragility curve parameters to get the median drift ratio for each damage state. Hazus uses a simple probabilistic model for these capacities. For example, a logarithmic standard deviation of 0.4 is used for all structural fragility curves (see Page 5-39 in the manual).

Hazus also has a special set of equivalent PGA-based fragility curves described in section 5.4.3. These were developed to allow efficient computations for components of utility and transportation systems, but are often used for regular building stock in the literature. The PID and PFA based curves are preferred over these if sufficient information is available to estimate those response quantities.


As for your question about running the same ground motion for all buildings, you would need to have the same ground motion assigned to all grid points. The simplest way to achieve this is to set the Number of neighbors to 1 and remove all but one grid points from the Event grid. Given a grid with only one point, the simulation engine will assign the same point (and the same ground motion) to every building. I assume you did something similar by assigning the same ground motion record to six grid points. That should also work fine.
The Number of samples in HTA controls how many realizations of ground motions (at each grid point) are considered in the analysis. This does not affect which ground motions are assigned to which building.

You mentioned that you received an error message when the number of neighbors and samples are both set to 1. Could you share the error message with us? This functionality should be supported and we are interested in reproducing and fixing this error.

Could you elaborate on what you see in the output that does not seem realistic?


 

[jia]

Thank you for your introduction on Hazus MH EQ.
set the Number of neighbors to 1 and remove all but one grid points from the Event grid, and set the number of neighbors to 1 and remove all but one grid points from the event grid. FileNotFoundError: [Errno 2] No such file or directory: 'EVENT.json'. Log file in the attachment.

Considering that the unit of the floor height in the building is feet, I input the unit as Feet in the GI interface, Meters per second squared in the HAZ interface, and feet in the building area in the ASD interface. May I ask whether the unit value is correct? If this is correct, the process should be fine. When the same ground motion is input, the result statistics show that the damage degree of concrete structure is higher than that of masonry structure on the whole, and the data amount is 5000 for concrete and 8000 for masonry.

[jia]

In addition, when the same ground motion was input and the results were counted, I excluded the influence of the age and the number of layers. The statistical number of layers was 6 and the age was around 1970.