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           A Joint Committee£¨ÁªºÏίԱ»á£©on Concrete and Reinforced Concrete was established in 1904 by the American Society of Civil Engineers£¨ÍÁľ¹¤³ÌʦЭ»á£©, American Society for Testing and Materials, the American Railway Engineering Association, and the Association of American Portland Cement Manufactures. This group was later joined by£¨¼ÓÈ룩the American Concrete Institute. Between 1904 and 1910 the Joint Committee carried out research. A preliminary £¨³õ²½µÄ£©report issued in 1913 lists the more important papers and books on reinforced concrete published£¨·¢±í£©between 1898 and 1911. The final report of this committee was published in 1916. The history of reinforced concrete building codes in the United States was reviewed£¨»Ø¹Ë£©in 1954 by Kerekes and Reid.
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           The design and construction of buildings is regulated£¨¿ØÖÆ£©by municipal bylaws£¨ÊÐÕþϸÔò£©called building codes. These exist to protect£¨ÓÃÒÔ±£»¤£©the public health and safety. Each city and town is free to£¨ÔÊÐí£©write£¨±àÖÆ£©or adopt its own building code, and in that city or town, only that particular code has legal status£¨ºÏ·¨µØ룩. Because of the complexity of building code writing, cities in the United States generally base their building codes on one of three model£¨µäÐÍ£©codes: the Uniform£¨Í³Ò»£©Building Code, the Standard Building Code, or the Basic Building Code. These codes cover£¨°üÀ¨£© such things as use and occupancy requirements, fire requirements, heating and ventilating£¨¹©ÈȺÍͨ·ç£© requirements, and structural design.
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            The definitive£¨×îÖյģ©design specification for reinforced concrete buildings in North America£¨±±ÃÀ£©is the Building Code Requirements for Reinforced Concrete (ACI-318-95), which is explained in a Commentary£¨ËµÃ÷£©.

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              This code, generally referred to as £¨Ö¸..£© the ACI Code, has been incorporated£¨ÌåÏÖ£©in most building codes in the United States and serves as the basis for comparable codes in Canada, New Zealand, Australia, and parts of Latin America. The ACI Code has legal status only if£¨Ö»Òª£©adopted in a local£¨µ±µØµÄ£©building code.

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            The rules for the design of concrete highway bridges£¨¹«Â·ÇÅ£© are specified in the Standard Specifications for Highway Bridges, American Association of State Highway and Transportation Officials£¨ÃÀ¹ú¹ú¼Ò¹«Â·ºÍÔËÊä¹Ù·½Ð­»á£©, Washington, D.C.£¨¸çÂ×±ÈÑÇ»ªÊ¢¶ÙÌØÇø£©.

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            Each nation or group of£¨Ò»Èº£©nations in Europe has its own building code for reinforced concrete. The CEB-FIP Model Code for Concrete Structures is intended to£¨ÓÃÀ´£©serve as the basis for future attempts to unify£¨Í³Ò»£©European codes. This code and the ACI Code are similar in many ways.

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UNIT 8
            A column is a vertical structural member transmitting axial compressive loads£¨Ñ¹ËõºÉÔØ£©, with or without moments. The cross-sectional dimensions of a column are generally considerably less than£¨Ô¶Ð¡ÓÚ£©its height. Columns support vertical loads from the floors and roof and transmit these loads to the foundations.