To provide a concrete segment and its manufacturing method to make it possible not only to make characteristics related to the specific function in the vicinity of the inner and outer peripheral surfaces of the concrete segment, for example, corrosion resistance and fire resistance variable but also to manufacture the concrete segment inexpensively and easily.
The protective layer 7 for forming the inner peripheral surface 4 of the concrete segment 1 is relatively provided in a thin-walled layered state and a relatively thick-walled concrete layer 8 is provided adjacent to a plate thickness direction. That is, protective mortar for forming the protective layer 7 is arranged in a form in a layered state to cast concrete for forming the concrete layer 8 in a semicured state and both layers are respectively cured, aged and demolded.
HASEGAWA SATOSHI
Tadashi Takahashi
Takashi Watanabe
Masakazu Aoyama
Suzuki Mitsuyoshi
Kazuya Nishi
Yasuhiko Murayama
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