A method for improving the seismic performance of bridges by utilizing the beam body and an energy dissipation and seismic mitigation bridge bearing, which can effectively eliminate the harmful vibration of the bridge pier in the inherent frequency band, thus reducing the stress of the pier body and improving the seismic performance of the bridge pier without introducing external additional mass and looking for an installation space on the pier. The method includes the following steps: obtain the natural frequency fi, the equivalent modal mass Mi and the modal stiffness Ki of the pier in the longitudinal or transverse direction by numerical modal analysis or experimental modal test; determine the mass mi of the beam body; calculate the connection stiffness ki and the connection damping ci between the beam body and the pier; select the bearing system with above connection stiffness ki and the connection damping ci.

This invention relates to a cut and cover method of constructing grade separation structures. The methods include partially burying precast substructure elements with associated trench boxes under live traffic. Once the precast substructure elements are buried the substructure is completed and the bridge span is installed. Other methods include installing precast superstructure elements with formwork system and forming a bridge substructure and excavating underneath the superstructure once the substructure is formed.

This invention relates to a cut and cover method of constructing grade separation structures. The methods include partially burying precast substructure elements with associated trench boxes under live traffic. Once the precast substructure elements are buried the substructure is completed and the bridge span is installed. Other methods include installing precast superstructure elements with form-work system and forming a bridge substructure and excavating underneath the superstructure once the substructure is formed.

A bridge system is provided that utilizes foundation structures that are formed of the combination of a metal-frame structure and cast-in-place concrete.

A bridge system is provided that utilizes foundation structures that are formed of the combination of a metal-frame structure and cast-in-place concrete.

A curved pathway including a double helix form with no center support column includes a plurality of segments, wherein each of the segments is formed from a plurality of rods coupled to a plurality of connecting nodes. The plurality of rods are arranged in a skewed tetrahedral geometry, which causes the plurality of stair segments to form a helical structure when the plurality of segments are coupled together. The plurality of rods form a spine on an underside of the plurality of stair segments. A pathway surface is coupled to each of the segments. In alternate embodiments, the curved pathway may be formed from sheet metal creased to form a plurality of linear support locations and connecting nodes.

A curved pathway including a double helix form with no center support column includes a plurality of segments, wherein each of the segments is formed from a plurality of rods coupled to a plurality of connecting nodes. The plurality of rods are arranged in a skewed tetrahedral geometry, which causes the plurality of stair segments to form a helical structure when the plurality of segments are coupled together. The plurality of rods form a spine on an underside of the plurality of stair segments. A pathway surface is coupled to each of the segments. In alternate embodiments, the curved pathway may be formed from sheet metal creased to form a plurality of linear support locations and connecting nodes.

A tunnel air-conditioning and heating apparatus is provided. the tunnel air-conditioning and heating apparatus may include a condenser provided at a rotunda; a compressor provided at the rotunda and connected to the condenser; an evaporator provided at a movable tunnel and connected to each of the condenser and the compressor; and a condenser connection pipe configured to connect the condenser with the evaporator and a compressor connection pipe configured to the compressor with the evaporator each of which is formed into a flexible coil.

A curved pathway including a double helix form with no center support column includes a plurality of segments, wherein each of the segments is formed from a plurality of rods coupled to a plurality of connecting nodes. The plurality of rods are arranged in a skewed tetrahedral geometry, which causes the plurality of stair segments to form a helical structure when the plurality of segments are coupled together. The plurality of rods form a spine on an underside of the plurality of stair segments. A pathway surface is coupled to each of the segments. In alternate embodiments, the curved pathway may be formed from sheet metal creased to form a plurality of linear support locations and connecting nodes.

A curved pathway including a double helix form with no center support column includes a plurality of segments, wherein each of the segments is formed from a plurality of rods coupled to a plurality of connecting nodes. The plurality of rods are arranged in a skewed tetrahedral geometry, which causes the plurality of stair segments to form a helical structure when the plurality of segments are coupled together. The plurality of rods form a spine on an underside of the plurality of stair segments. A pathway surface is coupled to each of the segments. In alternate embodiments, the curved pathway may be formed from sheet metal creased to form a plurality of linear support locations and connecting nodes.