When did they start using rebar in concrete?
Reinforcing bars in masonry construction have been used since at least the 15th century (2,500 meters of rebar was used in the Château de Vincennes). During the 18th century, rebar was used to form the carcass of the Leaning Tower of Nevyansk in Russia, built on the orders of the industrialist Akinfiy Demidov. The cast iron used for the rebar was of high quality, and there is no corrosion on the bars to this day. The carcass of the tower was connected to its cast iron tented roof, crowned with one of the first known lightning rods. However, it was not until the mid-19th century that rebar displayed its greatest strengths with the embedding of steel bars into concrete, thus producing modern reinforced concrete. Several people in Europe and North America developed reinforced concrete in the 1850s. These include Joseph-Louis Lambot of France, who built reinforced concrete boats in Paris (1854) and Thaddeus Hyatt of the United States, who produced and tested reinforced concrete beams. Joseph Monier of France is one of the most notable figures for the invention and popularization of reinforced concrete. As a French gardener, Monier patented reinforced concrete flower pots in 1867, before proceeding to build reinforced concrete water tanks and bridges.
When did they start using rebar in masonry?
15th century
Rebar
No context provided
When did the french start using rebar in concrete masonry?
1853
François Coignet was the first to use iron-reinforced concrete as a technique for constructing building structures. In 1853, Coignet built the first iron reinforced concrete structure, a four-story house at 72 rue Charles Michels in the suburbs of Paris. Coignet's descriptions of reinforcing concrete suggests that he did not do it for means of adding strength to the concrete but for keeping walls in monolithic construction from overturning. In 1854, English builder William B. Wilkinson reinforced the concrete roof and floors in the two-storey house he was constructing. His positioning of the reinforcement demonstrated that, unlike his predecessors, he had knowledge of tensile stresses.
When did the english start using rebar in concrete masonry?
1854
Reinforced concrete
Reinforced concrete
https://en.wikipedia.org/wiki/Reinforced%20concrete
Rebar
https://en.wikipedia.org/wiki/Rebar
Although rebar has been used in masonry since at least the 15th Century, it was not until the mid-19th century that the technique displayed its greatest strengths with the embedding of steel bars into concrete, thus producing modern reinforced concrete. For instance, the French only started implementing it around 1853, with the English following them  the next year, in 1854.