Abstract: The present invention relates to an earth anchor and a construction method therefor, and is for facilitating the installation of a wale member and a head block member by using a pedestal member mounted on the outer surface of a retaining wall which is supported by the earth anchor, enabling the construction process to be simplified, thereby shortening construction time and reducing the amount of steel needed and construction costs.

Abstract: The present invention relates to a gyroscope. Particularly, a ring-shaped rotary core in which magnetic bodies and nonmagnetic bodies are alternately arranged is provided to simplify the structure of the gyroscope and reduce the weight of the gyroscope. Also, due to reduced frictional resistance, noise can be minimized, and the speed at which the gyroscope rotates is markedly increased. As necessary, the gyroscope may be disposed within a sealed container to minimize a frictional loss and improve energy efficiency.

Abstract: The present invention relates to an earth anchor and a construction method therefor, and is for facilitating the installation of a wale member and a head block member by using a pedestal member mounted on the outer surface of a retaining wall which is supported by the earth anchor, enabling the construction process to be simplified, thereby shortening construction time and reducing the amount of steel needed and construction costs.

Abstract: The present disclosure relates to a floor slab structure for a bridge, the structure comprising: a girder-integrated floor slab having a girder member which is supported on a pier and supports a floor slab member, and which integrally protrudes from the lower surface of the floor slab member, multiple floor slab members being arranged to be connected in longitudinal and transverse directions; and a side barrier-integrated floor slab having a side bather member which integrally protrudes from the upper surface of one side of the floor slab member, multiple floor slab members being arranged to be connected in longitudinal and transverse directions. Accordingly, on-site work is minimized, the construction process for a bridge superstructure is simplified, the construction time period is shortened, the construction costs are significantly reduced, and the construction of skew bridges or curved bridges is simplified.

Abstract: An upper structure for a bridge includes a coping placed on the top end of a pier, and a girder held by the coping, wherein a side surface of the coping and an end surface of the girder are configured as inclined surfaces (or vertical surfaces), wherein a shear key protrudes on one of the inclined surfaces (or vertical surfaces), and a shear key slot is formed in another one of the inclined surfaces (or vertical surfaces) so as to be engaged with the shear key. The present disclosure can reduce the construction cost, can realize improved structural efficiency of the bridge upper structure, can realize an easy installation of the girders, can easily combine the girders with the coping without plastering or fixing with mortar by site work, and can efficiently resist to a shear stress that may be generated in the bridge.

Abstract: The present disclosure relates to a floor slab structure for a bridge, the structure comprising: a girder-integrated floor slab having a girder member which is supported on a pier and supports a floor slab member, and which integrally protrudes from the lower surface of the floor slab member, multiple floor slab members being arranged to be connected in longitudinal and transverse directions; and a side barrier-integrated floor slab having a side bather member which integrally protrudes from the upper surface of one side of the floor slab member, multiple floor slab members being arranged to be connected in longitudinal and transverse directions. Accordingly, on-site work is minimized, the construction process for a bridge superstructure is simplified, the construction time period is shortened, the construction costs are significantly reduced, and the construction of skew bridges or curved bridges is simplified.

Abstract: An upper structure for a bridge includes a coping placed on the top of a pier, and girders held by the coping, wherein the coping has girder holding grooves. The girders are installed continuously without using bridge bearings. The coping and the girders behave in an integrated state. The girders are held by being fitted into the grooves, so the coping is not excessively exposed to the outside. The girders and the coping are dry joined together in a prestressed state using prestressed steel strands. Further, the girders and the coping can be integrated with each other without being processed by site work.

Abstract: The present invention relates to a gyroscope. Particularly, a ring-shaped rotary core in which magnetic bodies and nonmagnetic bodies are alternately arranged is provided to simplify the structure of the gyroscope and reduce the weight of the gyroscope. Also, due to reduced frictional resistance, noise can be minimized, and the speed at which the gyroscope rotates is markedly increased. As necessary, the gyroscope may be disposed within a sealed container to minimize a frictional loss and improve energy efficiency.

Abstract: An upper structure for a bridge includes a coping placed on the top of a pier, and girders held by the coping, wherein the coping has girder holding grooves. The girders are installed continuously without using bridge bearings, thereby reducing the construction cost. The coping and the girders behave in an integrated state, thereby realizing improved structural efficiency. The girders are held by being fitted into the grooves, so the coping is not excessively exposed to the outside, thereby realizing a good appearance of the bridge. The girders and the coping are thy-joined together in a prestressed state using prestressed steel strands, so that the strength of the girders and the resistance to a negative bending moment can be increased. Further, the girders and the coping can be integrated with each other without being processed by site work, thereby realizing improved structural efficiency and reducing the construction period.

Abstract: An upper structure for a bridge includes a coping placed on the top end of a pier, and a girder held by the coping, wherein a side surface of the coping and an end surface of the girder are configured as inclined surfaces (or vertical surfaces), wherein a shear key protrudes on one of the inclined surfaces (or vertical surfaces), and a shear key slot is formed in another one of the inclined surfaces (or vertical surfaces) so as to be engaged with the shear key. The present disclosure can reduce the construction cost, can realize improved structural efficiency of the bridge upper structure, can realize an easy installation of the girders, can easily combine the girders with the coping without plastering or fixing with mortar by site work, and can efficiently resist to a shear stress that may be generated in the bridge.

Abstract: Provided is a hollow prestressed concrete girder for forming an I-type prestressed concrete girder bridge, in which at least one hole is formed in a body portion of the I-type prestressed concrete girder.

Abstract: Provided is a hollow prestressed concrete girder for forming an I-type prestressed concrete girder bridge, in which at least one hole is formed in a body portion of the I-type prestressed concrete girder.

Abstract: Disclosed herein is a support system that is temporarily placed below ground for preventing collapse of the excavated ground when a subway is constructed or a basement of a building is built. The excavated ground or load is supported by means of supporting members, the supporting members being pre-stressed by means of tensioning members and tendon support members serving to support the tensioning members. Consequently, the number of struts for supporting vertical piles and wales is considerably reduced so that obstacles in the under-ground space when it is excavated are removed. Furthermore, the constructional efficiency of the underground space is greatly improved, and the cost of construction is sharply reduced.

Abstract: In a method for designing a multi-step tension prestressed girder, prestress is appropriately introduced with respect to a relationship between a load and stress, for each step of construction, so that the height of a profile of the girder can be reduced. In a method for fabricating a multi-step tension prestressed girder, prestress is appropriately introduced with respect to a relationship between a load and stress, for each step of construction, so that the height of a profile of the girder can be reduced.

Abstract: An innovative prestressed scaffolding system is provided to use triangular tendon supports and tendons in place of a plurality of struts for supporting the earth pressure applied during an excavation or an underground construction structure, thereby removing the obstacles of the construction, e.g., intermediate piles or struts, and contributing to an improvement of the constructional efficiency of the underground space and reduction of construction costs.

Abstract: Disclosed herein is a support system that is temporarily placed below ground for preventing collapse of the excavated ground when a subway is constructed or a basement of a building is built. The excavated ground or load is supported by means of supporting members, the supporting members being pre-stressed by means of tensioning members and tendon support members serving to support the tensioning members. Consequently, the number of struts for supporting vertical piles and wales is considerably reduced so that obstacles in the under-ground space when it is excavated are removed. Furthermore, the constructional efficiency of the underground space is greatly improved, and the cost of construction is sharply reduced.

Abstract: A prestressed concrete girder having an adjustable load bearing capacity includes a concrete girder including an upper flange, and at least one non-attached steel wire installed in the upper flange of the girder and extending in a lengthwise direction of the girder. A method of adjusting a load bearing capacity of a bridge using a prestressed concrete girder having an adjustable load bearing capacity including non-attached steel wires capable of being cut at an upper flange is also disclosed.