The prestigious academic military journal, Oblicza Wojny, published by the The Distinguished University of Lodz in Poland has published following article on Sassanian siege warfare (available for download in pdf):
The above article provides an in-depth examination of Sassanian siege warfare and technology in the domains of ballistae, “scorpions”, catapults, and battering rams.
One of the lecture slides pertaining to Sassanian siege engines presented by Kaveh Farrokh during the “8th Scientific Conference Faces of War – Tools of War” held at The University of Lodz in Poland in June 1-2, 2023.
Readers further interested in siege warfare may be interested in the following book (available for download in pdf):
Sassanian siege warfare necessitated the use of protection-shielding for personnel (combat troops, engineers, laborers), mounds, mining, scaling of walls, as well as the digging of ditches and trenches. Archery barrages played a seminal role in support of siege operations.
One of the lecture slides pertaining to Sassanian archers during sieges presented by Kaveh Farrokh during the “8th Scientific Conference Faces of War – Tools of War” held at The University of Lodz in Poland in June 1-2, 2023.
The Arteshtārān (lit. warriors; mainly Paighan infantry, archers and Savārān cavalry) and Pil–Savār war elephants would undertake in combat operations (for example at Nisibis 350 CE) with manual labor provided by peasant recruits.
One of the lecture slides pertaining to Sassanian siege engines presented by Kaveh Farrokh during the “8th Scientific Conference Faces of War – Tools of War” held at The University of Lodz in Poland in June 1-2, 2023.
Sassanian troops were often engaged in close quarters combat in siege warfare operations, notably when attempting to capture Roman-held cities and fortresses.
A video and cinematic reconstruction by the Karzar Nameh history venue of the history of the Battle of Amida in 359 CE (Source: Karzar Nameh in YouTube). Kindly note that video is narrated in Persian, however the content is accessible by way of English-language captions.
In conclusion, Sassanian siege warfare capabilities appear to have achieved proficiency levels equivalent to contemporary Roman armies.
