| 摘要 |
A manhole cover includes a support having an upper surface and a peripherally-extending portion. An outer insulating member is disposed over the entire upper surface of the support, and the support comprises a first material and the outer insulating member comprises a second material different from the first material. The peripherally-extending portion of the support is positionable over the lip of the manhole ring. The outer insulating member is positionable between the upper surface of the support and the upper surface of the rim of the manhole ring when the manhole cover is received in the manhole ring. In one aspect, the support comprises cross-members defining a grate having passageways through the support. In another aspect, the support comprises metal, and the outer insulating member comprises a composite of resin, reinforcement fibers, and stone aggregate. In another aspect, screen inserts are disposed in a plurality of passageways in the outer insulating member.
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