Minister of Culture and Tourism Mehmet Nuri Ersoy announced that during the restoration and strengthening works at Haydarpaşa Train Station, it was determined that 80 percent of approximately one thousand wooden piles at the foundation of the historical building were destroyed and there was a risk of liquefaction on the ground.
GAVE THE DATE
Ersoy stated that the calendar was rearranged due to the carried out bored pile and injection applications and technical inspections, and stated that they aim to complete the first stage of the project in 2027.
In his post on his social media account, Ersoy shared with the public the new findings obtained in the restoration and strengthening works carried out at Haydarpaşa Train Station and the opening goal of the first stage.
Ersoy stated, "While carrying Haydarpaşa into the future, we reached a critical finding regarding the foundations of the historical station building. In georadar examinations of approximately 1000 wooden piles in the original projects, it was determined that only 200 piles were in place. Technical investigations revealed that approximately 80 percent of the wooden piles were destroyed over time."
Stating that ground investigations revealed a risk of liquefaction in loose and water-saturated ground, Ersoy noted that if this risk occurs, settlement and lateral movement of the structure may occur.
"FOUNDATION AND GROUND WERE STRENGTHENED"
Emphasizing that they acted in line with scientific evaluations to protect the historical structure against the identified risks, Ersoy said:
"In order to protect the historical building against these risks, we carried out bored pile and ground strengthening injection applications around the building, in line with the project prepared by expert engineers, examined by academic committees and deemed appropriate by our Advisory Board. We proceeded in a controlled manner by monitoring the behavior of the structure with technical devices at every stage."
Reminding that the first stage was previously planned to be opened at the beginning of the Istanbul Cultural Road Festival, Ersoy stated that the work schedule had to be rearranged due to sensitive strengthening applications, scientific analyzes and project revisions.
APPROXIMATELY THOUSAND WOODEN PILES FROM ORIGINAL PROJECTS WERE EXAMINED
During historical research on Haydarpaşa Train Station, the original projects of the building were also reached.
As a result of the examination of the projects, it was seen that approximately a thousand wooden piles with lengths ranging from 8 to 21 meters and diameters of 50 to 90 centimeters were placed under the foundation during the first construction.
In the georadar study carried out to determine the current status and number of piles, it was determined that 200 piles were in place and 800 piles were not. In technical evaluations, this was recorded as a finding showing that approximately 80 percent of the wooden piles have disappeared since the date of construction.
ENGINEERING APPLICATIONS AGAINST LIQUECUTION, SETTLEMENT AND LATERAL SPREAD RISKS
Drilling, field and laboratory tests, geophysical measurements and instrumental observation studies were carried out in order to determine the existing ground conditions and investigate the deformations observed on the ground surface around the building.
As a result of the examinations, it was determined that the soil, which was determined to be in the ZF class, consisted of heterogeneous fill and liquefiable sand, and was loose and saturated with water.
It was determined that the ground contains significant geotechnical risks and that in case of liquefaction, settlement and lateral spreading movements may occur in the structure.
In line with these findings, the ground improvement project prepared by expert engineers was examined by expert academic committees and was found appropriate by the Advisory Board.
Within the scope of the project, bored piles were manufactured around the building in order to prevent lateral spreading. Ground reinforcement applications such as compaction injection and polymer injection were carried out inside and outside the building.
Experimental and observational data were collected periodically during the applications. According to the results obtained, necessary revisions were made to the projects. The technical review, evaluation and revision processes, as well as the work required by the reinforcement applications, caused the work program to be reconsidered and the implementation period to be extended.
CONTINUOUSLY MONITORED WITH YAPI TEKNİK DEVICES
Before ground reinforcement works began at Haydarpaşa Train Station, technical monitoring devices were installed to monitor the behavior of the structure during manufacturing. Reinforcement applications were carried out in a controlled and gradual manner by constantly monitoring the behavior of the structure in line with the data obtained from the devices.
Due to the limited working conditions in the basement, delicate applications had to be made with appropriate equipment. Proceeding the historical building without damaging its existing load-bearing system and in coordination with the superstructure manufacturing also required additional time.
"WE AIM TO COMPLETE THE FIRST STAGE IN 2027"
Minister Ersoy stated that they carried out the most comprehensive restoration in the history of the Haydarpaşa Station Site, with works covering the historical station building, which was officially opened in 1909, and the cultural heritage around it, and stated that the area will be brought into the cultural life of Istanbul with a museum, library and art venues.
Ersoy said, "Our priority is to preserve this unique heritage with all its values and carry it safely to the future. We aim to complete the first phase of our work in 2027 and introduce it to our citizens."
MOVING PROCESS DELAYED THE START OF WORK IN SOME AREAS
While the conservation of existing ruins in the Haydarpaşa Archaeological Park area continues, new archaeological ruins were unearthed during excavations regarding infrastructure, drainage and visitor circulation routes.
Infrastructure and drainage lines, as well as visitor routes, were rearranged taking into account the locations and preservation status of existing and newly discovered ruins. Additional work required to preserve new finds also affected the implementation schedule.
The relocation processes of buildings, facilities, equipment and usage areas belonging to different institutions at Haydarpaşa Station Site were also effective in the application sequence.
Due to the waiting for the moving process to be completed, the planned production in some sections could not start in the expected time. It also required additional time to prepare the evacuated areas for application and to make the necessary field arrangements.
HAYDARPAŞA WILL MEET CULTURE AND ART
Within the scope of the protocol signed between the Ministry of Culture and Tourism and TCDD on August 15, 2024, the works carried out at Haydarpaşa Station Site include conservation and strengthening practices, as well as the creation of new cultural and artistic areas.
The project includes the Anatolian Side's first archaeological museum, performing arts center, library, exhibition halls and art and design workshops. It is aimed to bring Haydarpaşa into the cultural life of Istanbul with the archeopark, open activity areas and landscaping arrangements.
