荷载、强度和结构安全

河北建筑工程学院毕业设计（论文）外文资料翻译 系别： 土木工程系 专业： 土木工程专业 班级： 工 043 班 姓名： 臧海月 学号： 19 外文出处： English Civil Engineering （用外文写） 附 件：1 、外文原文； 2 、外文资料翻译译文。 指导老师评语：签字： 年 月 日注：请将该封面与附件装订成册。1、 外文原文Loads, Strength, and Structural SafetyA. Loads Loads that act on structures are usually classified as dead loads or live loads. Dead loads are fixed in location and constant in magnitude throughout the life of the structure. Usually the self-weight of a structure is the most important part of the dead load. This can be calculated closely, based on the dimensions of the structure and the unit weight of the material. Concrete density varies from about 90 to 120 pcf ( 14 to 19 kN/m3) for lightweight concrete, and is about 145 pcf (23 kN/m3) for normal concrete. In calculating the dead load of structural concrete, usually a 5 pcf ( 1 kN/m3) increment is included with the weight of the concrete to account for the presence of the reinforcement. Live loads are loads such as occupancy, snow, wind, or traffic loads, or seismic forces. They may be either fully or partially in place, or not present at all. They may also change in location. Although it is the responsibility of the engineer to calculate dead loads, live loads are usually specified by local, regional, or national codes and specifications. Typical sources are the publications of the American National Standards Institute, the American Association of the State Highway and Transportation Officials and, for wend loads, the recommendations of the ASCE Task Committee on Wind Force. Specified live loads usually include some allowance for overload, and may include dynamic eff...