شكرا لكل من شارك في هذا الموضوع الشيق الجميل وقمه الجمال فكره العقبري الذي فكر كيف يلاشي عزم الانحناء بعزم خارجي وبعكس اتجاهه وبذلك حول القطاع الي قطاع ضغط قادره الخرسانه علي تحمله وبمعامل امان لقدرتها الهائله علي تحمل الضغط وقد تصل الي 60 نيوتن/مم2 ونجح في ذلك محققا انتصارا عظيما في مجال الهندسه المدنيه ونقله كبيره جدا بفكره الراقي والممتع
فاحببت ان انقل لكم قصه هذا العبقري بلغه الانجيليزيه التي اوصلت لنا هذا العلم
The man known as "Mr. Prestressed Concrete" was born in Fuzhou, China in 1912. As a boy, his first career choice was to become a politician, but his father encouraged him to pursue a career in engineering.
The Master of Prestressed Concrete
Educated at home in his youth, the boy did not begin formal schooling until he was 11 years old. Nonetheless, he passed the college entrance exams at the age of 14 with the top math score at Jiaotong University's Engineering School and went on to earn a B.S in Civil Engineering.
This son of a Chinese Supreme Court Justice then moved to the U.S. and earned a Master's Degree in Civil Engineering at UC Berkeley. His master's thesis on direct moment distribution was the first student thesis ever published by ASCE.
In 1933, the newly graduated engineer moved back to China, where he worked for the Yunnan-Chongqing Railroad. At the age of 25 he became the railroad's chief engineer and he oversaw the survey, design and construction of more than 1,000 bridges in China's mountainous regions.
After World War II, he accepted a teaching position at UC Berkley and immigrated to the U.S. with his wife. It was there that he began his pioneering research on prestressed concrete that changed the history of building - making possible today's high rises and long-span structures.
His list of projects include ground-breaking structures throughout the world. He designed the Moscone Convention Center in San Francisco - a massive earth-covered structure having the largest underground room in the world when built in 1982. He also designed the first prestressed-steel arch bridge in the world at the Twin Cities in Minnesota.
His own home in El Cerrito, CA was the first residential structure in the world constructed using prestressed concrete.
He received numerous awards during his lifetime, including the National Medal of Science in 1986 - the highest scientific honor in the U.S.
Who was this pioneering engineer?
Tung-Yen "T.Y." Lin was recognized as one of the greatest pioneering leaders in the fields of long-span construction and prestressed concrete. In 1954, at the age of 42, he established a consulting firm in San Francisco that still exists to this day. In 1994, the San Francisco Chronicle reported, "Lin is perhaps the greatest structural engineer in the world, and surely the most fearless."
In addition to his pioneering designs, Lin published the first textbook on prestressed concrete construction. And he organized the first World Conference on Prestressed Concrete in 1957, which was attended by more than 1,200 engineers, architects and contractors from around the world.
Lin held numerous positions at UC Berkley through the years, including chair of the Division of Structural Engineering and Structural Mechanics. He retired from UC Berkley in 1976 to lead his consulting firm, T.Y. International full time. He left the firm in 1992 and formed Lin Tung-Yen China, Inc., which focused on engineering projects in China.
When Lin received the National Medal of Science in 1986, he handed President Reagan a 16-page plan for a 50-mile bridge linking Alaska and Siberia. While his bridge, named the Intercontinental Peace Bridge, has never been built, the plan demonstrated the technical feasibility of this difficult project. Lin described how to overcome the Arctic elements by prefabricating sections of the bridge in port and floating the sections into place.
In addition to the National Medal of Science, Lin was a member of the National Academy of Scientists and received the ACEC Medal of Honor, Freyssinet Medal, the 1994 UC Berkeley Alumnus of the Year, and the Albert Caquot of France Award. He was the first recipient of the ASCE's Outstanding Lifetime Achievement in Design Award. Lin contributed more than 100 technical and research papers and co-authored three textbooks in structural engineering. Many of his works are considered "bibles of the industry".
T.Y. Lin passed away on November 15, 2003. He was survived by his wife of 62 years and two children. Ben C. Gerwick, Jr., a UC Berkeley professor emeritus of civil engineering said of Lin, "He was far ahead of his time. He always wanted what he was doing in the technical and structural field to carry over to society in a broader way. His enthusiasm inspired creativity in engineers throughout the world."