| 摘要 |
A straight steel curb for the steel curb faced concrete curb of a roadway has a vertical sidewall and a horizontal portion. Two sheet metal or plastic benches, which lie on the floor of the trench, are aligned relative to a string line. Each bench has a bracket which supports a bottom edge of the steel curb at its two ends, to position the steel curb. The front plate and back plate of a bench are welded to the bottom plate by a weak weld which shears under the pressure of the expanding or contracting concrete or has a pleated base which contracts and expands. The bench has front and back flanges which, respectively, hold front and back concrete forms.
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