Lesson Plan • Review • New Words and Phrases • Reading and Translating—Unit Twelve • Classroom Exercises Review Unit Twelve Load of High-rise Building 单 元 12 高层建筑荷载 Dead Loads Dead loads are defined as fixed, nonmovable loads of a permanent nature which can be divided into two categories: (1) self weight of the structure (2) superimposed dead loads. Dead Loads Dead loads are defined as fixed, nonmovable loads of a permanent nature which can be divided into two categories: (1) self weight of the structure (2) superimposed dead loads. 恒载 恒载定义为固定的、不可移动的、永久性的 荷载。它可分为两类: (1) 结构自重, (2) 附加的恒载 The self-weight of the structure includes all beams, girders, columns, slabs, walls, bracing, and any other structural elements. Concrete framing systems are typically heavier than steel framing systems, which can sometimes be an advantage from a wind overturning standpoint but can also be a disadvantage in terms of seismic and foundation considerations. The self-weight of the structure includes all beams, girders, columns, slabs, walls, bracing, and any other structural elements. Concrete framing systems are typically heavier than steel framing systems, which can sometimes be an advantage from a wind overturning standpoint but can also be a disadvantage in terms of seismic and foundation considerations. 结构自重包括所有梁、大梁、柱、板、墙、 支撑及任何其它结构构件。典型的混凝土框架体 系比钢框架体系重。从风力倾覆的角度考虑,这 是有利的,但是从基础及抗震角度考虑这是不利 的。 Superimposed dead loads consist of partitions, ceilings, hung mechanical/electrical loads (e.g., sprinklers, lights, etc.), special floor fills and finishes, facade weight, and any other dead load which acts in addition to the weight of the structural elements. Superimposed dead loads consist of partitions, ceilings, hung mechanical/electrical loads (e.g., sprinklers, lights, etc.), special floor fills and finishes, facade weight, and any other dead load which acts in addition to the weight of the structural elements. 附加的恒载包括隔墙、顶棚、悬挂的设备 或电器的荷载 ( 如喷淋设备、灯等 ),特殊的楼 板填充饰面、立面重量及除结构自重以外的其 它恒载。 The lightweight partition types that are utilized in modern high-rise buildings usually result in an equivalent uniform superimposed dead load ranging between 400 and 600N/m2. For preliminary design, however, it is prudent to include a 1kN/m2 allowance for partitions since the actual partition types, weights, and locations are often not defined at this stage. The lightweight partition types that are utilized in modern high-rise buildings usually result in an equivalent uniform superimposed dead load ranging between 400 and 600N/m2. For preliminary design, however, it is prudent to include a 1kN/m2 allowance for partitions since the actual partition types, weights, and locations are often not defined at this stage. 现代高层建筑通常使用的轻型隔墙的等效均 布附加恒载为400~600N/m2, 然而在初步设计时, 为谨慎起见,隔墙采用1kN/m2 的许可值,因为 实际隔墙的类型、重量及其位置在此阶段经常不 能确定。 Suspended ceiling weights and mechanical/ electrical loadings vary from project to project, depending upon the type of occupancy and the type of structural system utilized, and usually range between 100 and 500N/m2. Suspended ceiling weights and mechanical/ electrical loadings vary from project to project, depending upon the type of occupancy and the type of structural system utilized, and usually range between 100 and 500N/m2. 吊顶重量和设备或机电荷载随工程而异, 它取决于使用类型和所用结构体系的类型,通 常为 100~500N/m2。 Floor fills or other special floor finishes can result in significant dead loads. Examples are brick or stone pavers in lobby areas, concrete fill over a waterproofing membrane for mechanical room floors. Floor fills or other special floor finishes can result in significant dead loads. Examples are brick or stone pavers in lobby areas, concrete fill over a waterproofing membrane for mechanical room floors. 楼板填充物或其它特殊楼板饰面会产生很大 恒载。例如大厅的砖石铺地、设备间楼板防水膜 上的混凝土填充物。 The facade weight can vary significantly, depending upon the type of facade to be used, for example, glass curtain wall, precast concrete, masonry, or stone. The weight of glass curtain wall systems usually ranges between 400 and 600N/m2, but the weight of precast or masonry facades can be 2~4KN/m2 or more. The facade weight can vary significantly, depending upon the type of facade to be used, for example, glass curtain wall, precast concrete, masonry, or stone. The weight of glass curtain wall systems usually ranges between 400 and 600N/m2, but the weight of precast or masonry facades can be 2~4KN/m2 or more. 立面重量由于所采用的装饰材料的类型不 同差别很大,如玻璃幕墙、预制混凝土、砖 或 石。玻璃幕墙体系的重量通常为400~600N/m2, 但预制(空心)混凝土或砖石立面(砌块墙) 为2~4kN/m2或更多。 Live Loads Live loads are nonpermanent in nature and vary depending upon the usage of the building floor area. For example, most building codes specify a minimum design live load of 2.5KN/m2 for typical office areas. Live Loads Live loads are nonpermanent in nature and vary depending upon the usage of the building floor area. For example, most building codes specify a minimum design live load of 2.5KN/m2 for typical office areas. 活载 活载实际上是非永久荷载,它随楼面的用 途不同而不同。例如,很多建筑规范规定典型 办公室的最小设计活载为2.5kN/m2。 Increased live loads for special usage areas that are known at the time of preliminary design should be taken into account, such as lobbies, restaurants, mechanical equipment rooms, cooling towers, landscaped planting areas, computer rooms, and places of assembly. Increased live loads for special usage areas that are known at the time of preliminary design should be taken into account, such as lobbies, restaurants, mechanical equipment rooms, cooling towers, landscaped planting areas, computer rooms, and places of assembly. 初步设计中应当考虑在已知的专门使用区上 增加的活载,如大厅、餐馆、机械设备室、冷却 塔、景观种植区、计算机房及人流集中的地方。 Localized areas to be used for storage or heavy filing loads are often unknown at the time of preliminary design and, therefore, must be taken into account during final design or, as sometimes is necessary, during or after construction. Localized areas to be used for storage or heavy filing loads are often unknown at the time of preliminary design and, therefore, must be taken into account during final design or, as sometimes is necessary, during or after construction. 在初步设计阶段,用于储存或归档重物荷 载的局部区域是未知的,所以必须在最后设计 中考虑,必要时经常在施工过程中或以后考虑。 Roof live loads, which will be a very small portion of total gravity load, include snow loads with due consideration given to drifting, for example, at vertical surfaces of parapets, awning, and adjacent structures. Allowable reductions of live load in accordance with applicable building code provisions should be applied during the preliminary design phase. Roof live loads, which will be a very small portion of total gravity load, include snow loads with due consideration given to drifting, for example, at vertical surfaces of parapets, awning, and adjacent structures. Allowable reductions of live load in accordance with applicable building code provisions should be applied during the preliminary design phase. 屋顶活荷载是整个重力荷载中的很小一部 分。它包括:应适当考虑堆积的雪荷载,例如 在女儿墙、雨篷以及相邻结构的竖直面处。按 照适用的建筑规范,在初步设计阶段,应当允 许活荷载折减。 Wind Loads Outside of high-risk seismic zones,wind is the force that most affects the design of high-rise buildings. For this reason, a brief summary of current approaches for determining wind force is presented here. Wind Loads Outside of high-risk seismic zones,wind is the force that most affects the design of high-rise buildings. For this reason, a brief summary of current approaches for determining wind force is presented here. 风载 在非强震区,风载对高层建筑设计影响最大。 因此,这里简要概括确定风力的常用方法。 For preliminary design, wind loads are usually derived from the wind pressures specified in the governing building codes. The wind loads acting on the overall structure are generally given as stepped increments of wind pressure along the height of the building, with the pressures increasing in magnitude as the height above ground level increases. For preliminary design, wind loads are usually derived from the wind pressures specified in the governing building codes. The wind loads acting on the overall structure are generally given as stepped increments of wind pressure along the height of the building, with the pressures increasing in magnitude as the height above ground level increases. 初步设计中,风载是根据所使用的建筑规范 规定的风压计算出来的。一般作用于整体结构上 的风荷载沿建筑物的高度逐步增加,离地越高, 风压越大。 These wind loads are taken to act normal to the vertical surfaces of the building with consideration also given to the effect of lateral wind loads. For certain configurations of the structural bracing system, lateral wind loads can be much more severe than normal wind loads. These wind loads are taken to act normal to the vertical surfaces of the building with consideration also given to the effect of lateral wind loads. For certain configurations of the structural bracing system, lateral wind loads can be much more severe than normal wind loads. 所取的风荷载是垂直于建筑物竖直表面的, 同时也要考虑侧向风荷载的效应。对于某些结构 支撑体系的布置,侧向风荷载比垂直风荷载更有 威胁。