Ir. Johan Hasiholan Simanjuntak (JHS) was born in Sidikalang, North Sumatra on 30       October 1937. He was the third child of four of J. Wolter Simanjuntak and Karianna     Sianturi. JHS pursued elementary and junior high school education in his hometown,   Sidikalang. He then moved to Balige, a small town on the south side of Lake Toba, to   complete his senior high school education at SMAN 1 Balige.

After completing high school, he went to Bandung Institute of Technology (ITB) in 1957,   majoring in civil engineering. Being an ITB student was a dream come true for JHS. It   turned to be a start of his successful career in building and construction sector. With   perseverance and determination, he achieved a bachelor’s degree in 1963.

JHS started his career at PT. Adhi Karya, a state-owned enterprise. During his tenure,   he was involved in numerous iconic megaprojects, such as Sarinah Building (the first   trading center and skyscraper in Jakarta), Istiqlal Mosque, Hotel Indonesia, and     Semanggi Interchange. His last position at the company was Technical Director.

After deciding to leave PT. Adhi Karya in 1982, he established PT. JHS Piling System, a piling services company. The company continues to grow rapidly, supported by formation of new companies as parts of JHS Group. Now, JHS Group is one of the largest private companies in precast concrete in Indonesia.

Throughout his career, JHS was always active in research and development to foster innovation in precast concrete. His inventions were widely recognized by national and international community. They were patented in Indonesia, United States of America, and United Kingdom. He received awards for his merits in the construction sector, including:

• Patent Inventor Award from Directorate General of Intellectual Property Rights of Ministry of Law and Human Rights (2014)
• Ganesa Widya Jasa Adiutama Award from Bandung Institute of Technology (2017)
• Inventor of Splice for Joining PC Pile Bullet Award from Museum Rekor Dunia Indonesia (MURI) (2018)

The following are the articles about JHS:

• “Tiang-tiang Hasiholan” - Tempo Magazine / 1984
• “Kemenkum HAM Gelar Konvensi HKI dan Beri 10 Penghargaan Bagi Kreator” - Detik.com News / 2014
• “ITB Gelar Sidang Terbuka Peringatan 97 Tahun Pendidikan Tinggi Teknik di Indonesia” - ITB News / 2017
• “Tiga Batak Di Balik Pembangunan Masjid Istiqlal” - DetikX Article / 2019