This is the modification of gmsim_v15.1.1 based on the work of Robin Lee in 2017/2018. Specifically,:
-Removing the long period site amplification (or reducing to a 1-2s taper as opposed to the previous 2-5s taper?)
This change to reduce the long period site amplification was as a result of the CB14 site amplification overamplifying long periods since it double counts for velocity features which are already explicitly modelled in the LF simulations (due to the high resolution 3DVM).
Changing - Changing the HF path duration from Dp = 0.07R to the Boore and Thomson (2014) path duration developed using the NGA-West2 database.
This change to increase the HF path duration was a result of the durations being identified as too short when compared to observed ground motions.
---More details needed here.