Paving material for absorbing electromagnetic wave and pavement structure using it
First Claim
1. A road comprising:
- a substructure disposed at a lower portion of a pavement for forming a paved road; and
a surface course having an electromagnetic wave absorption function disposed above the substructure of the pavement, the surface course being formed by a course of an electromagnetic wave-absorbing pavement material and having such a thickness as to enable attenuation of electromagnetic waves and prevention of interference caused by reflection of the electromagnetic waves when the electromagnetic waves which have entered the top surface of the surface course pass through the surface course, reflect off the bottom surface thereof and pass through the surface course again.
1 Assignment
0 Petitions
Accused Products
Abstract
An electromagnetic absorber formed of conductive fiber or the like, such as carbon fiber having an overall length corresponding to the wavelength of electromagnetic waves to be absorbed, is mixed into a base material to form an electromagnetic wave-absorbing pavement material. The electromagnetic wave-absorbing pavement material is used to form a pavement having an electromagnetic wave absorbing course. Further, an electromagnetic wave reflecting course is disposed under the electromagnetic wave absorbing course, and the electric length of the electromagnetic wave reflecting course is set to a predetermined value in relation to the dielectric constant so that electromagnetic waves reflecting off the surface of the electromagnetic wave absorbing course and electromagnetic waves reflecting off the electromagnetic wave reflecting course have opposite phases and thereby cancel each other out, whereby the electromagnetic waves are absorbed well. Moreover, the pavement having the electromagnetic wave absorbing course is formed such that the average dielectric constant along a plane orthogonal to a direction of thickness of the electromagnetic wave absorbing course increases from the top surface to the bottom surface thereof. With this structure, the electromagnetic waves easily enter the top surface of a surface course formed of the electromagnetic wave-absorbing pavement material. Thus, the electromagnetic waves directly reflecting off the top surface of the surface course formed of the electromagnetic wave-absorbing pavement material (i.e., directly reflected waves) are reduced, such that the proportion of the electromagnetic waves entering the surface course formed of the electromagnetic wave-absorbing pavement material is increased. As a result, the electromagnetic waves are efficiently absorbed by the electromagnetic wave absorbing course.
-
Citations
18 Claims
-
1. A road comprising:
-
a substructure disposed at a lower portion of a pavement for forming a paved road; and
a surface course having an electromagnetic wave absorption function disposed above the substructure of the pavement, the surface course being formed by a course of an electromagnetic wave-absorbing pavement material and having such a thickness as to enable attenuation of electromagnetic waves and prevention of interference caused by reflection of the electromagnetic waves when the electromagnetic waves which have entered the top surface of the surface course pass through the surface course, reflect off the bottom surface thereof and pass through the surface course again. - View Dependent Claims (4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 17)
-
-
2. A road comprising:
-
a substructure disposed at a lower portion of a pavement for forming a paved road; and
a surface course having an electromagnetic wave absorption function disposed above the substructure of the pavement, the surface course being formed by a course of an electromagnetic wave-absorbing pavement material and having a thickness large enough to absorb electromagnetic waves while the electromagnetic waves which have entered the top surface of the surface course proceed toward the bottom surface of the surface course, thereby attenuating the electromagnetic waves and preventing interference caused by reflection of the electromagnetic waves.
-
-
3. A road comprising:
-
a substructure disposed at a lower portion of a pavement for forming a paved road;
an electromagnetic wave reflecting course disposed above the substructure of the pavement in the form of a course to reflect electromagnetic waves; and
a surface course having an electromagnetic wave absorption function, the surface course being formed by a course of an electromagnetic wave-absorbing pavement material and being disposed so as to closely contact the top surface of the electromagnetic wave reflecting course of the pavement, wherein the surface course having the electromagnetic wave absorption function has a thickness D set by the expression D=λ
(n+1)/4 COS θ
, wherein λ
is a wavelength of the electromagnetic waves, which are to be absorbed, in the pavement material, n is a natural number, and θ
is an incidence angle of the electromagnetic waves, and reflected electromagnetic waves to be absorbed, which reflect off the top surface of the surface course, and reflected electromagnetic waves to be absorbed, which enter the surface course and reflect off the electromagnetic wave reflecting course, have opposite phases so as to cancel each other out. - View Dependent Claims (14)
-
-
18-19. -19. (Cancelled)
Specification