The first use of concrete as a major material for bridge construction was in 1856. It was used to form a multi-arch structure at the Grand Maître aqueduct in France, in which the concrete was cast in its crudest form, a huge unreinforced mass subjected to compaction according to the procedure devised by François Coignet.[6] Later in the 19th century, engineers explored the possibilities of reinforced concrete as a structural material. They discovered that it supported compressive forces, while the steel bars supported tensile stresses. This made concrete a material with characteristics more suitable for the design of all types of structures.

French inventor Joseph Monier is credited with being the first to understand the principles of reinforced concrete, when he had the idea of ​​embedding an iron wire mesh into concrete. He was a gardener, not a licensed engineer, and sold his patents to contractors who built the first generation of reinforced concrete bridges in Europe. He also perfected the prestressed concrete technique, which allows permanent compression stresses to be introduced into concrete pieces.[7]​.

By the turn of the century, reinforced concrete became an acceptable substitute for all previous structural building materials, such as stone, wood, and steel. People like Monier had developed useful techniques for design and construction, but no one had created new forms that fully displayed the aesthetic possibilities of reinforced concrete.

Robert Maillart had an intuition and a genius that exploited the aesthetics of concrete. He designed tri-articulated arches in which the deck and arch ribs were combined to produce closely integrated structures that evolved into very thin rigid reinforced concrete arches and concrete slabs. The Salginatobel Bridge (1930) and the Schwandbach Bridge (1933) are classic examples of tri-articulated arch bridges and arch bridges reinforced with Maillart deck, respectively. They have been recognized for their elegance and their influence on the design and engineering of later bridges.[8]​.

These concepts went beyond the common limits of design in Maillart's time. The two bridges mentioned above are excellent examples of his ability to simplify the project in order to allow maximum use of materials and incorporate the natural beauty of the structure's surroundings. Selected from among 19 participants in a design competition (partly due to the low cost of his proposal), Maillart began the construction of the Salginatobel bridge in 1929, next to the town of Schiers, which would be inaugurated on August 13, 1930.

Maillart is also known for his revolutionary design of mushroom-shaped columns in a series of buildings. He built his first such roof for a warehouse in Zurich and treated the concrete deck as a slab, rather than reinforcing it with beams. One of his most famous achievements is the design of the columns in the water filtration plant at Rorschach. Maillart decided to abandon standard methods to create "the most rational and beautiful European construction method." His design of the columns included widening the tops to reduce the bending moment between the columns. With the widening, slight arches were formed to transfer the loads from the roof to the columns.

He also flared the bottom of the columns to reduce the pressure (load per unit area) in the support areas above the ground. By widening the bottom of the columns, the load area is distributed more widely and therefore the resulting compression value is reduced.

Many of his predecessors had employed this method using wood and steel, but Maillart was revolutionary by being the first to use concrete. He used concrete because it could effectively support the weight of a considerable layer of earth provided as insulation against freezing.

His technique was used to build the Ponte Del Ciolo (Bridge of Ciolo), which is located in Ciolo, in Apulia.

All parts and components of the bridge were integrated based on their constructive function, so that the road is no longer a weight that the arch must support but rather a constructive element that cooperates as another resistant part of the structure.[9]​ Their bridges seek to overcome the old principle of separation between own weight and useful loads. In this way, Maillart's bridges become works of art due to the economy of means, the harmonious balance and the constructive force (traditionally, any bridge, viaduct, culvert or similar element that serves to bridge a dip in the ground has been called a "work of art").

Its main innovation is the three-jointed box girder used for the Tavanasa Bridge over the Rhine River, built in 1905 and destroyed by an avalanche in 1927.[10]​.

Among its architectural structures, notable ones are the Chiasso Customs Warehouse in 1924 and the large concrete warehouse for the 1939 Swiss National Exhibition held in Zurich.

The most important invention applied to buildings was the construction of ceilings without beams supported on capitals in 1908, a technique that spread throughout the world from 1910 onwards. In this construction system the column - beam - slab transition is eliminated and only the column - slab transition remains light and slender. This saves material, execution time and gives flexibility to the design, with the additional benefit of lightness and elegance.[11]​.

By the second half of the century, important advances had been made in design theory, graphic statics, and knowledge of the resistance of materials. As the century drew to a close, the major factor contributing to the need for scientific bridge design was railroads. Engineers had to know the precise stress levels in the bridge elements to accommodate the large loads generated by the trains. The first design solution was obtained by Squire Whipple in 1847. His greatest advance was that the elements of a structure could be analyzed as a set of parts subjected to a system of forces in equilibrium. This system, known as the "knot method", allows the determination of the forces in all the elements of a lattice if the forces acting on it are known. The next advance in design was the "method of sections", developed by Wilhelm Ritter in 1862. Ritter simplified force calculations by developing a very simple formula for determining the forces in the elements contained in a cross section.[16] A third advance was a better method of graphical analysis, developed independently by James Clerk Maxwell (in the United Kingdom) and Karl Culmann (from Switzerland).

Robert Maillart learned the analytical methods of his day, but was most influenced by the principles developed by his mentor, Wilhelm Ritter, mentioned above. Maillart studied under Ritter, who had three basic design principles. The first was to assess the calculations based on simple analysis, so that appropriate assumptions could be made based on common sense. The second was to carefully consider the process of building the structure, not just the final product. The last principle was to always test a structure with full-scale load tests. All of these principles are an adaptation of available techniques, but with an emphasis on careful study of previously built structures.

In Maillart and Ritter's time, other designers preferred their designs to evolve from previously successful structures and designs. German engineers and scientists had developed elaborate mathematical techniques and were confident that they did not need practical load testing of their designs developed with those techniques. However, these techniques did not encourage designers to think about unusual shapes, because those shapes could not be fully analyzed using the mathematical techniques available. Ritter's principles had the advantage that they allowed unusual forms to be adopted.

The first use of concrete as a major material for bridge construction was in 1856. It was used to form a multi-arch structure at the Grand Maître aqueduct in France, in which the concrete was cast in its crudest form, a huge unreinforced mass subjected to compaction according to the procedure devised by François Coignet.[6] Later in the 19th century, engineers explored the possibilities of reinforced concrete as a structural material. They discovered that it supported compressive forces, while the steel bars supported tensile stresses. This made concrete a material with characteristics more suitable for the design of all types of structures.

French inventor Joseph Monier is credited with being the first to understand the principles of reinforced concrete, when he had the idea of ​​embedding an iron wire mesh into concrete. He was a gardener, not a licensed engineer, and sold his patents to contractors who built the first generation of reinforced concrete bridges in Europe. He also perfected the prestressed concrete technique, which allows permanent compression stresses to be introduced into concrete pieces.[7]​.

By the turn of the century, reinforced concrete became an acceptable substitute for all previous structural building materials, such as stone, wood, and steel. People like Monier had developed useful techniques for design and construction, but no one had created new forms that fully displayed the aesthetic possibilities of reinforced concrete.

Robert Maillart had an intuition and a genius that exploited the aesthetics of concrete. He designed tri-articulated arches in which the deck and arch ribs were combined to produce closely integrated structures that evolved into very thin rigid reinforced concrete arches and concrete slabs. The Salginatobel Bridge (1930) and the Schwandbach Bridge (1933) are classic examples of tri-articulated arch bridges and arch bridges reinforced with Maillart deck, respectively. They have been recognized for their elegance and their influence on the design and engineering of later bridges.[8]​.

These concepts went beyond the common limits of design in Maillart's time. The two bridges mentioned above are excellent examples of his ability to simplify the project in order to allow maximum use of materials and incorporate the natural beauty of the structure's surroundings. Selected from among 19 participants in a design competition (partly due to the low cost of his proposal), Maillart began the construction of the Salginatobel bridge in 1929, next to the town of Schiers, which would be inaugurated on August 13, 1930.

Maillart is also known for his revolutionary design of mushroom-shaped columns in a series of buildings. He built his first such roof for a warehouse in Zurich and treated the concrete deck as a slab, rather than reinforcing it with beams. One of his most famous achievements is the design of the columns in the water filtration plant at Rorschach. Maillart decided to abandon standard methods to create "the most rational and beautiful European construction method." His design of the columns included widening the tops to reduce the bending moment between the columns. With the widening, slight arches were formed to transfer the loads from the roof to the columns.

He also flared the bottom of the columns to reduce the pressure (load per unit area) in the support areas above the ground. By widening the bottom of the columns, the load area is distributed more widely and therefore the resulting compression value is reduced.

Many of his predecessors had employed this method using wood and steel, but Maillart was revolutionary by being the first to use concrete. He used concrete because it could effectively support the weight of a considerable layer of earth provided as insulation against freezing.

His technique was used to build the Ponte Del Ciolo (Bridge of Ciolo), which is located in Ciolo, in Apulia.

All parts and components of the bridge were integrated based on their constructive function, so that the road is no longer a weight that the arch must support but rather a constructive element that cooperates as another resistant part of the structure.[9]​ Their bridges seek to overcome the old principle of separation between own weight and useful loads. In this way, Maillart's bridges become works of art due to the economy of means, the harmonious balance and the constructive force (traditionally, any bridge, viaduct, culvert or similar element that serves to bridge a dip in the ground has been called a "work of art").

Its main innovation is the three-jointed box girder used for the Tavanasa Bridge over the Rhine River, built in 1905 and destroyed by an avalanche in 1927.[10]​.

Among its architectural structures, notable ones are the Chiasso Customs Warehouse in 1924 and the large concrete warehouse for the 1939 Swiss National Exhibition held in Zurich.

The most important invention applied to buildings was the construction of ceilings without beams supported on capitals in 1908, a technique that spread throughout the world from 1910 onwards. In this construction system the column - beam - slab transition is eliminated and only the column - slab transition remains light and slender. This saves material, execution time and gives flexibility to the design, with the additional benefit of lightness and elegance.[11]​.

By the second half of the century, important advances had been made in design theory, graphic statics, and knowledge of the resistance of materials. As the century drew to a close, the major factor contributing to the need for scientific bridge design was railroads. Engineers had to know the precise stress levels in the bridge elements to accommodate the large loads generated by the trains. The first design solution was obtained by Squire Whipple in 1847. His greatest advance was that the elements of a structure could be analyzed as a set of parts subjected to a system of forces in equilibrium. This system, known as the "knot method", allows the determination of the forces in all the elements of a lattice if the forces acting on it are known. The next advance in design was the "method of sections", developed by Wilhelm Ritter in 1862. Ritter simplified force calculations by developing a very simple formula for determining the forces in the elements contained in a cross section.[16] A third advance was a better method of graphical analysis, developed independently by James Clerk Maxwell (in the United Kingdom) and Karl Culmann (from Switzerland).

Robert Maillart learned the analytical methods of his day, but was most influenced by the principles developed by his mentor, Wilhelm Ritter, mentioned above. Maillart studied under Ritter, who had three basic design principles. The first was to assess the calculations based on simple analysis, so that appropriate assumptions could be made based on common sense. The second was to carefully consider the process of building the structure, not just the final product. The last principle was to always test a structure with full-scale load tests. All of these principles are an adaptation of available techniques, but with an emphasis on careful study of previously built structures.

In Maillart and Ritter's time, other designers preferred their designs to evolve from previously successful structures and designs. German engineers and scientists had developed elaborate mathematical techniques and were confident that they did not need practical load testing of their designs developed with those techniques. However, these techniques did not encourage designers to think about unusual shapes, because those shapes could not be fully analyzed using the mathematical techniques available. Ritter's principles had the advantage that they allowed unusual forms to be adopted.