Abstract:
PURPOSE: A nail with an excellent gripping force and excellent workability and a construction method thereof is provided to improve the gripping force at an end portion due to the blowing portion of an expansion portion during nail construction. CONSTITUTION: A nail with an excellent gripping force comprises a support portion(100) and a head portion. The support portion is separated a long support portion and a front support portion and is connected with a coupler. The head portion comprises a fixed body(210), an expansion portion(230), a front case(240), and a fixture(250). The fixed body comprises an outer taper and an inner taper. The expansion portion is expanded in order to prevent the pullout of the nail by a fixed wedge inserted around. The front support portion is fixed on the fixed body and includes a stopper(241) protruded to an internal space. The fixture is fixed on one side of the support portion and includes a female screw penetrated by a bolt in order to insert a bolt.
Abstract:
PURPOSE: An anchor with a spiral unit and a method of constructing using the anchor and a vegetation mat are provided to enable easy installation of an anchor, firm installation and fixation of a vegetation mat and prevent the separation of the vegetation mat. CONSTITUTION: An anchor(10) comprises a shaft(11), and a spiral unit(12). The shaft is formed in a cylinder shape so that the central part of the shaft is hollow. A plurality of fixing holes(11b) are formed on the upper surface of the shaft. The spiral unit is protruded along the outer circumferential surface of the fixing hole in a spiral shape.
Abstract:
PURPOSE: A FRP(Fiber Reinforced Plastic) lagging and a sheathing method for engineering works using the same are provided to facilitate sheathing work in a curve shape by a FRP lagging whose shape can be freely changed. CONSTITUTION: A FRP lagging(30) comprises polyethylene resin, an FRP panel, and a rectangular steel pipe. As a glass fiber mat is impregnated with mixture to a thickness of 0.8~1.5cm, the FRP panel is formed. The mixture is made of talcum or calcium carbonate and sepiolite which are mixed at a weight rate of 1:1:0.1. The rectangular steel pipe is placed on one side of the FRP panel into the shape of a grille.
Abstract:
PURPOSE: A grouting method using a grout composition is provided to ensure excellent injection capability, durability, ground improvement effect and high water resistance by producing a cement-based grout admixture. CONSTITUTION: A grouting method using a grout composition comprises the steps of: injecting an accelerating agent into pores in the ground by a low pressure injector after drilling the ground; injecting a finishing material into pores in which the accelerating agent is injected by the low pressure injector to condition the ground. The accelerating agent includes the grout composition and a silicate glass admixture consisting of 35-45 parts by weight of silicate glass, 20-30 parts by weight of water based on 100 parts by weight of the grout composition in a volume ratio of 1:1.
Abstract:
PURPOSE: A shear reinforcing system for a joint between a column and a slab is provided to reduce the whole weight by manufacturing using small-diameter bars, to obtain the excellent shear reinforcing effect using structural specificity, to manufacture and construct easily with simple structure and to function as a spacer for keeping an interval between upper and lower bars of a slab. CONSTITUTION: The shear reinforcing system installed on a joint between a column and a slab of a reinforced concrete structure to increase the resistance against shear failure contains: one or more upper anchorages(10) where thin and long bars are installed horizontally; one or more lower anchorages(20) arranged in parallel with the upper anchorages(10); and an intermediate shear member(30) placed longitudinally between the upper anchorage(10) and the lower anchorage(20) to have a vertical unit(32) and an inclined unit(34) repeatedly.
Abstract:
PURPOSE: Provided are a surface coating material for preventing neutralization and salt damage of concrete structure and its coating method. The material is a mixture of photocatalyst, water soluble modified acryl resin, cellulose fiber and cement. The coating composition is applied to the surface of the cement structure such as bridges, tunnels, cover structures and other concrete structures to protect them from atmospheric pollutant such as carbon dioxide, hydrogen sulfide, salt and calcium chloride and eliminate the surface pollution by oxidizing them through photocatalyst using UV light. Further more the coating is tensile at room and low temperature so that it does not break down due to the fine rupture of the concrete structure. CONSTITUTION: The composition comprises: 30-50 wt.% of cement, 10-30wt.% of silica fume, 0.5-5wt.% of cellulose fiber with 0.01-0.05mm circumference, 1-6mm length and tensile strength of 3,000-8,000kgf/cm; 1-5wt.% of titanium dioxide, 0.5-2wt.% of mixing agent, 15-25wt.% of water soluble modified acryl resin and 20-35% of water. The coating method includes: washing the structure with high pressure water of 200-300bar; applying the first coating by spraying the composition with 5-10bar pressure to make 70-80mm thickness coating; spray coating secondly before 5 hours of drying the first coating with 5-10bar pressure to make the coating thickness of 200-400micrometer and hardening the coating with avoiding the direct sunlight.
Abstract:
PURPOSE: An anti-neutralizing agent for organic-inorganic complex concrete and a method for repairing and reinforcing concrete using the same are provided to prevent the salt damage and the neutralization of a concrete structure using a curing agent based on polyurethane-acryl polymer and silica sol. CONSTITUTION: An anti-neutralizing agent for organic-inorganic complex concrete is based on a main material and a hardening agent at the weight ratio of 8-9.5:1. The main material is polyurethane-acryl polymer. 60-80 parts by weight of silica powder, 10-20 parts by weight of sepiolite powder, and 1-2 parts by weight of a thickening agent are included in 100 parts by weight of the polyurethane acryl polymer. The hardening agent includes 50-100 parts by weight of lithium silicate and 50-100 parts by weight of water based on 100 parts by weight of silica sol. The polyurethane acryl polymer includes isocyanate, polyglycol, dimethylol propionic acid, triethyl amine, ethylene diamine, sodium persulfate, 2-hydroxy ethylmethacrylate, and n-butyl acrylate.