Earthquake Ground Motion Levels
The relevant earthquake level specified in TBDY 2018 is selected by the user according to the design according to the strength or the design according to the deformation
According to TBDY 2018 - 3.5.1 - Table 3.4 (a), DD-2 selection is required for Normal Performance Target and Earthquake Ground Motion Level and Performance Level are determined automatically.
Within the scope of TBDY 2018, four different earthquake ground motion levels are defined below.
2.2.1. Earthquake Ground Motion Level-1 (DD-1)
DD-1 Earthquake Ground Motion , spectral magnitude of 2% probability of exceedance in 50 years and the corresponding return period of 2475 years is very rare characterizes the earthquake ground motion. This earthquake ground motion is also called the largest earthquake ground motion considered.
2.2.2. Earthquake Ground Motion Level-2 (DD-2)
DDR-2 earthquake ground motion , spectral magnitude of 10% probability of exceedance in 50 years and against it from the repetition period of 475 years is rare characterizes the earthquake ground motion. This earthquake ground motion is also called standard design earthquake ground motion .
2.2.3. Earthquake Ground Motion Level-3 (DD-3)
DDR-3 Earthquake Ground Motion , spectral magnitude of 50% probability of exceedance in 50 years and the corresponding return period of 72 years that often characterizes the earthquake ground motion.
2.2.4. Earthquake Ground Motion Level-4 (DD-4)
DD-4 earthquake ground motion , the probability of exceedance in 50 years spectral magnitude of 68% (50% probability of exceedance in 30 years) and the corresponding return period of 43 years that so often characterizes the earthquake ground motion. This earthquake ground motion is also called service earthquake ground motion .
There is approximately 1.5 times the difference between each earthquake level. Different earthquake levels are defined to be used in the 'Performance Assessment and Design ' section, which was not available in DBYBHY 2007 and was added as a new assessment and design approach with TBDY 2018 for the first time . In accordance with the philosophy of 'Performance-Based Evaluation and Design' , design is not made with a single earthquake level, it is necessary to make calculations and designs for different earthquake levels.
