In fact in the th century

In fact, in the 17th century craftsmen in Roussilon area of South France developed a type of flat vault, so called Roussilon Vault, to be used in both public and private buildings. These vaults were built of one or more layers of thin tiles laid in quick-setting plaster mortar on a movable centering with a low elliptical profile. This technique was brought to Catalonia of Spain later, and because of cheap cost, for centuries “the builders of Catalonia and Roussillon had employed light, flat, tile vaults in barns, stables, granaries, coach houses, and even churches” (Figure 13). This system of vaulting differs from traditional vault construction in that they are thinner, have a lower rise, and are capable of covering greater spans than stone vaults, setting the foundation for Catalan vaulting manner to which the Guastavino system belonged. This method of vaulting, later considered as a symbol of the Catalan nationalistic movement, cannot only be used to build roofs and floors, but also applied to walls and facades, as innovatively shown in Antonio Gaudi׳s and Cesar Martinell׳s works. Rafael Guastavino, Sr. (1842–1908) is the pivotal figure that popularized this vaulting method and introduced it order MLN4924 to the US. Trained in the art of Catalan construction and timbrel vaulting, Guastavino immigrated to the United States in 1881, bringing with him the technique of Catalan vaulting and his son, Rafael Guastavino, Jr. The elder Guastavino termed his vaulting method “Guastavino Dome and Ribs system” and focused on marketing the fireproof abilities of his construction methods and founded the Guastavino Fireproof Construction Company in 1889 (Figure 14). Meanwhile, newly invented Portland cement was used in place of mortar, so that workers were able to work overhand in assembling the vaults saving a lot of money and time, which neither freshly poured-concrete nor formed voussoir arches. Moreover, in the 1920s, Rafael Guastavino, Jr., collaborated with Harvard׳s acoustical expert, Wallace C. Sabine, in devising an acoustically effective tile for vault and wall surfaces, hence the Rumford Tile and its upgrade Akoustolith, were able to effectively absorb sounds to improve acoustic quality. For the next 70 years since its establishment, the Guastavino Company which obtained 24 patents all together would play a significant role in proliferating dome construction in other building types such as commercial and religious institutions (Figure 15). The introduction of the steel frame and domestic Portland-cement production, the imperative of developing fireproof-construction techniques, and the flowering of large-scale public architecture in America׳s cities presented tremendous opportunities for the Guastavino׳s system. In the years preceding the advent of Guastavino construction in America, significant dome construction generally appeared limited to State Capitol buildings and some educational institutions. These domes were typically of heavy masonry construction or cast iron, requiring metal framework to support the dome itself. Besides, finished Guastavino work was so attractive that the company׳s vaults began to be installed for purely esthetic reasons, apart from a building׳s structural system.
Field measurement and analysis of the Auditorium and its dome Since its completion in April 1921, the Auditorium has gone through numerous renovation and maintenance. For example, in the 1960s, the foundation of the Auditorium was changed into an air-raid shelter, due to tense relation with the Soviet Union; in 1991 on the eve of Tsinghua׳s 90th anniversary, the inner dome was plastered; and then with acoustic renovation all chairs were replaced and the basement was enlarged in 2009. However, the Auditorium was never measured on a full scale, as no drawings or any records on the dome that is concealed beyond sight has ever been discovered, except for the original design of the dome produced by Murphy as shown in Figure 8. Therefore, the author organized students from the School of Architecture at Tsinghua University to measure the Auditorium in July 2013. Aware of the previous work, we put our emphasis on the actual structural form of the dome, in comparison to the original design.