Abstract: Plural penetration holes 3a are formed in the side wall of a base 3, and ends 6a, 7a of reinforcements 6, 7 of an RC pavement 2 laid around the light embedded area are inserted into the penetration holes 3a, and the peripheral edge of each penetration hole 3a and the ends 6a, 7a of the reinforcements 6, 7 are firmly fixed by welding. Since the ends 6a, 7a of the reinforcements 6, 7 of the RC pavement 2 and the base 3 are mutually fixed, the load applied to the inset light 1 from above is dispersed not only into the portion contacting with the lower side of the base 3 of the RC pavement 2, but also into the reinforcements 6, 7, and the sinking shearing resistance of the RC pavement 2 is extremely improved. Accordingly, if a heavy load of aircraft or the like is applied, the inset light capable of preventing sinking of the RC pavement in the lower part of the base is presented.

Abstract: A piping joint for preventing pipe members laid across the connection end faces of two adjacent structural elements from being damaged by changes in the relative positional relationship between the two adjacent structural elements due to the expansion and contraction caused by changes in the temperature or external stresses. The piping joint connects the end portions of the two pipe members laid in two structural elements whose connection end faces can displace relatively to each other, between the connection end faces to make the two pipe members communicate. It comprises a fixed unit (30) fixedly embedded into the connection end face of one of the structural elements and a movable unit (50) supported by the fixed unit so as to be movable along the connection end face. The pipe member in the structural element is connected to the fixed unit, and the pipe member in the other structural element is connected to the movable element. The two pipe members communicate in the fixed unit.

Abstract: The invention provides a concrete composition used in an overlay method of construction which is used for improving a deteriorated paved surface and/or a paved layer, the concrete composition comprising a cement, a shrink-reducing agent, an expanding agent, a high performance AE water-reducing agent and an AE agent, wherein the cement is a normal portland cement and/or a low heat portland cement. The concrete composition used in an overlay method of construction is rich in the bonding strength between an existent paved layer and a new surface layer and is resistant to exfoliation, cracking of a new surface layer and wear.

Abstract: Provided is an overlay concrete which is good in bond to existing concrete fabrics and satisfies properties such as strength, durability and workability. The overlay concrete of the present invention comprises an AE water reducing agent or superplastisizer, and has a slump of 2 to 8 cm, a cement-water ratio of 35 to 45%, and a sand-coarse aggregate ratio of 36 to 42%.

Abstract: In an inset light 1 comprising a cylindrical base 3 installed in a PC pavement 2, and a lamp body 5 held in the upper part of the base 3 for emitting light outside of the pavement surface, protruded deformations 6 are formed on the outer circumference of the base 3 so as to receive the load applied on the lamp body 5 from above at the PC pavement 2 around the base 3. As a result, concentration of load in the lower part of the base 3 is prevented. Further, to alleviate the prestress shortage of the PC pavement in the lower part of the base 3, a shock absorber 7 is provided in the lower end outer peripheral edge of the base 3. As a result, lowering of strength of the PC pavement 2 in the lower part of the base 3 is suppressed. Accordingly, if a heavy load of aircraft or the like is applied, the inset light capable of preventing sinking while suppressing brittleness of the PC pavement in the lower portion of the base can be presented.

Abstract: When the unevenness quantities of the surface of a surface-treated, existing concrete are measured at a given pitch by a measuring device 10, the measured unevenness quantities are automatically collected by a CPU 21 to calculate the characteristic quantities of the surface-treated form of the existing concrete. The CPU 21 compares the calculated characteristic quantities with characteristic quantities beforehand stored in a data ROM 23 to give an evaluated result of the surface-treated form automatically. The evaluated result is displayed on a display device 40 or printed by a printer 50, so that the result can be immediately checked. An ideal surface-treated form is a surface-treated form in which the average height of unevenness of the surface of the existing concrete is from 13 to 35% of the maximum particle size of aggregates contained in the existing concrete, and the slope length ratio thereof is 1.