PROBLEM TO BE SOLVED: To provide a floor slab reinforcing method for preventing adhesion of a fiber reinforced concrete layer and an asphalt mixture layer from being lowered even when construction of repairing an existing asphalt mixture layer is performed, and providing flexural strength and flexural toughness equal to or more than those of a conventional steel fiber reinforced concrete layer.SOLUTION: The floor slab reinforcing method includes a fiber reinforced concrete layer forming step and an asphalt mixture layer forming step. In the fiber reinforced concrete layer forming step, concrete containing cement, aggregates, organic fibers and water is coated on a floor slab 11 to form a fiber reinforced concrete layer 12. In the asphalt mixture layer forming step, a waterproof layer and an asphalt mixture layer 13 are formed on the fiber reinforced concrete layer 12. In the fiber reinforced concrete layer forming step, fiber assemblies of organic fibers are used for the organic fibers.

Floor slab reinforcing method

The invention provides a one-step forming construction method for an expressway high-modulus asphalt composite (HMAC, namely the EME), and relates to the technical field of highway pavement construction and design. According to the method, in the mixing, transportation and paving procedures of the high modulus asphalt composite, the composite is controlled at a preference temperature, wherein the temperature during stirring is 160-180 DEG C; each disc of the composite is mixed for 54-60 s; a provided asphalt transferring trolley of a continuous feeding device moves before a paver to be tightly connected with the paver, and the temperature of the asphalt composite is not smaller than 140 DEG C; in the paving procedure, semi-range, overall-width and one-time paving is realized by the paver, and the paver is guided by stranded wires or controlled by a double-levelling beam with the length of 14 m; the one-time paved asphalt composite is 14-15 cm in thickness, the vibration frequency of a rammer of the paver is about 1400-1600 rev/min, the vibration frequency of a tamping plate of the paver is about 1900-2200 rev/min, and the walking speed of the paver during construction is not greater than 1.5 m/min. The method overcomes defects that in the traditional EME construction, roller compaction is difficult due to the loss of the temperature of a base layer, the asphalt composite is difficult to compact, and regulatory requirements cannot be met due to poor adhesion between the layers of the asphaltic composite.

One-step forming construction method for expressway high-modulus asphalt composite

PROBLEM TO BE SOLVED: To provide a floor slab and the like made of lightweight concrete, which have high water resistance, are lightweight and obtain sufficient strength.SOLUTION: A road structure 3 comprises a floor slab 31, a water-resistant layer 33 and a pavement layer 35. The floor slab 31 is a RC floor slab using concrete that contains an expansive material and a lightweight aggregate. A low addition type expansive material is used as the expansive material and mixed in the concrete so that a ratio of the low addition type expansive material becomes 20 kg or more and 40 kg or less per 1 mof the concrete. A water-binder ratio at the time of the preparation of the concrete is adjusted to be 38 wt.% or more and 42 wt.% or less.

Floor slab made of lightweight concrete and road structure

PROBLEM TO BE SOLVED: To provide a construction method for thickening the upper surface of a floor slab for reinforcing a concrete floor slab of a road bridge by thickening its upper surface, wherein the necessary strength as the concrete floor slab is secured, the minimum construction thickness of a thickening layer is reduced, and a concern of corrosion is eliminated even in an area where antifreezing-agent is sprayed. SOLUTION: An asphalt pavement 16 formed on the upper surface 14a of a concrete floor slab 14 is removed, to roughen the upper surface. The roughened upper surface 14a of the concrete floor slab 14 is then provided with a thickening layer 20 formed thereon with highly elastic resin mortar having a Young's modulus that is 1/3 or more of the Young's modulus of the concrete composing the concrete floor slab 14. Thereby, even if the minimum construction thickness of the thickening layer 20 is set to be relatively thin, the required strength is secured, which reduces a bending stress. The highly elastic resin mortar has salt-proofing properties, which eliminate the concern of the corrosion of reinforcing bars, etc., inside the concrete floor slab even in the area where the antifreezing agent is sprayed. COPYRIGHT: (C)2011,JPO&INPIT

Construction method for thickening upper surface of floor slab

A screed assembly is disclosed for use with a paving machine having a machine frame. The screed assembly may have a main frame operatively connected to the machine frame, and a sub-frame with a body and a screed plate. The screed assembly may also have a vibration isolator disposed between the main frame and the sub-frame, and at least one adjustment mechanism disposed between the body and the screed plate. The at least one adjustment mechanism may be configured to adjust a flatness of the screed plate. The screed assembly may further have a vibration device connected to the body of the sub-frame and configured to vibrate the sub-frame.

Paving machine having vibration-isolated screed assembly

PROBLEM TO BE SOLVED: To improve not only quality by enhancing the durability of a floor slab but also reducing vibration and noise generated by construction, while a thickness is smaller than that in a conventional floor slab upper-surface thickness increasing construction method. SOLUTION: The surface of an existing floor slab 1 used for a bridge and a superhighway is ground, polished and cleaned, and soft concrete 2 of a slump of 10 cm or larger is placed for covering the surface of the ground, polished and cleaned floor slab 1, and the soft concrete 2 is compacted and integrated into the existing floor slab 1 by imparting high frequency vibration to a screed plate 12 of a concrete finishing device 10. The soft concrete 2 includes water, a hydraulic setting composition, an aggregate, an expansive admixture and fiber. The hydraulic setting composition uses a material for revealing a compressive strength of 10 N/mm 2 or higher in 2-3 hours after construction as a hardening speed of the soft concrete 2. COPYRIGHT: (C)2009,JPO&INPIT

明夫荒井

Papers

Floor slab reinforcing method and concrete finishing device used therefor

明夫 荒井

Papers

Floor slab reinforcing method and concrete finishing device used therefor

明夫荒井