Structural behaviour of cantilever beams.

Famous photograph by Benjamin Baker, in which through a living model the cantilever structural principle on which the solution to the Firth Bridge over the Forth was based was depicted.

"To illustrate the structural theory of a cantilever beam (Gerber), a human demonstration was carried out. The loads were represented by the person sitting in the middle of the span of the suspended span. The arms of the persons seated on both sides represented the traction at the joints; the wooden bars, the compression at the lower elements, and the bricks, the anchor points located at the pylons. The chairs represent the granite piles. Imagine the chairs 500 m apart and the men's heads as high as St. Paul's cross (London church, 104 m) their arms represented by steel beams and the canes by 3.5 m diameter tubes at the base you get a good notion of the structure."

Heinrich Gerber applied in 1866 a theory that consisted in subdividing the continuous beam through ball-and-socket joints "which define a point of zero bending moment". This type of beam with intermediate joints is what is now known as a Gerber beam. The position where these hinges are located allows influencing the behavior of the beam; therefore, it is not only used directly in some structures, but in some projects a real beam can be idealized by assimilating it to a Gerber beam, whose isostatism allows a simple approximate calculation.

Comments

Ayn Rand

Ayn Rand Alice O'Connor (born Alisa Zinovyevna Rosenbaum; February 2, 1905 – March 6, 1982), better known by her pen name Ayn Rand, was a Russian-born American author and philosopher. She is known for her fiction and for developing a philosophical system she named Objectivism. Born and educated in Russia, she moved to the United States in 1926. After two early novels that were initially unsuccessful and two Broadway plays, Rand achieved fame with her 1943 novel The Fountainhead. In 1957, she published her best-selling work, the novel Atlas Shrugged. Afterward, until her death in 1982, she turned to non-fiction to promote her philosophy, publishing her own periodicals and releasing several collections of essays. Rand advocated reason and rejected faith and religion. She supported rational and ethical egoism as opposed to altruism. In politics, she condemned the initiation ...

Native American Sign Language

Native American sign language Illustrated guides to 400 gestures The illustrations above showing how to communicate using Native American/”Indian” sign language, come from two vintage sources — one in the ’50s, and the other (more comprehensive guide) from the ’20s. Indian Sign Language (1954) From The Golden Digest, Issue 1 (1954) Once they had many Indian tribes in America. They did not all speak the same language. But with sign language, one tribe could understand another. Here are some things they would say. Words shown: Sunset Yes I/me/my Go/go away Horse/horse rider Buffalo Man Rising sun Tipi You Night Native American Sign Language is a visual communication system developed by Indigenous tribes for intertribal dialogue and storytelling. It showcases the cultural depth and linguistic creativity of Native American societies. Native American Sign Language (NASL), also known as Plains Indian Sign Language, is a sophisticated, visual-gestural communi...

Remna Ni – Mizoram’s Day of Peace and Unity

Remna Ni, celebrated annually on June 30th in the northeastern state of Mizoram, holds a place of profound historical and emotional significance for the Mizo people. Known as “Peace Day,” Remna Ni commemorates the signing of the Mizo Peace Accord in 1986, which brought an end to two decades of insurgency and unrest in the state. It is a day not only to remember the past but to celebrate the return of peace, stability, and democratic progress in Mizoram. The origins of Remna Ni lie in a long period of political turmoil. In the 1960s, due to dissatisfaction with the Indian government’s handling of famine and development in the Mizo Hills (then part of Assam), the Mizo National Front (MNF) launched an armed uprising in 1966, demanding independence. What followed was twenty years of armed conflict, curfews, and deep unrest that affected thousands of lives. For two decades, Mizoram remained under military and political tension, isolated from the developmental mainstream of India. ...

Creative Edge

Search This Blog