关于组合梁桥构造细节设计有关问题的探讨

Discussion on the Detailed Design of the Composite Beam Bridge Structure in China

近年来,虽然我国公路钢结构桥梁建设取得了较大成就,但由于钢结构桥梁具有专业性强、工艺性高的特点,加之设计单位与制造单位协同性较差,设计人员往往忽略钢桥梁制造的工艺性。因此,钢结构桥梁制造过程中呈现出设计与制造之间脱节的现象。为提高设计人员对钢结构桥梁构造细节处理的意识,结合我国多座组合梁桥对钢桥梁构造细节方面进行了较详细说明。钢结构桥梁设计和制造脱节及构造细节处理内容主要体现在:1)由于钢厂轧制能力、市场供应、供货量大小等方面影响,造成部分钢板或型钢无法采购;2)钢桥梁设计时宜将制造节段内腹板或盖板的厚度统一,以减少制造资源浪费;3)组合梁构件工厂内宜采用焊接连接,安装节段接口连接宜采用高强度螺栓连接;结构设计时需考虑螺栓施拧空间、桥位安装关系等;为防止发生漏浆现象,钢混结合面橡胶条厚度不宜过小;横坡设计时宜通过调整纵梁高程来实现,上盖板可设置成水平状态,通过橡胶条的可压缩性实现横坡变化;4)组合梁钢板梁制造线形应为“恒载+1/2活载”的反向拱度叠加桥梁纵坡产生的竖向线形,同时应考虑架设施工工况对桥梁成桥线形的影响;为实现标准化制造,钢板梁制造节段曲线矢高较小时,宜采用“以直代曲”方案;组合梁防撞护栏设计时应考虑钢结构构件与混凝土预制件的精度关系;5)钢桥梁应按需要合理设置焊接接头,尽量减少过度焊接带来的损伤,对于有熔深要求的部分熔透角焊缝应作出明确要求;6)耐候钢桥梁设计时需注意桥面板防水、梁体通风、支座防护等细节,同时根据桥梁所处环境确定涂装或免涂装使用;7)常规跨径桥梁具有线路长、线形复杂的特点,可采用“通用图+专用图”设计模式,为确保施工详图转化过程中桥梁线形和构件连接关系的准确性,选择合理的详图转化方式较为关键。所阐述的钢结构桥梁构造细节处理内容,对于改善钢结构桥梁设计和制造脱节现象、提升我国钢结构桥梁设计人员构造细节处理水平具有较强的指导意义,亦为类似钢结构桥梁设计、制造提供了借鉴。

In recent years,although China’s highway steel structure bridge construction has made great achievements,but as a result of steel bridge professional characteristics of strong,high technology,combined with the collaborative design and manufacturing unit is poorer,designers often ignore the technology of steel bridge manufacture,so in the process of steel bridge manufacture,presents the design and manufacture of the disconnect between phenomenon,in order to improve design staff awareness of steel bridge structure detail processing,combining with our country more than combination bridge of steel bridge construction details for more detailed instructions.The disjunction between the design and manufacturing of steel bridge is mainly reflected in:1)Some steel plates or sections cannot be purchased due to the influence of rolling capacity,market supply and supply quantity of the steel mill;2)In the design of steel bridge,the thickness of webs or cover plates in the manufacturing segment should be unified to reduce the waste of manufacturing resources;3)The composite beam members should be welded in the factory,and the installation segment interface should be connected by high-strength bolts.In the structural design,the screw space of bolts and the bridge installation relationship should be considered.In order to prevent the occurrence of slurry leakage,the thickness of the rubber strip should not be too small;The transverse slope design is realized by adjusting the height of the longitudinal beam.The upper cover plate can be set in a horizontal state,and the transverse slope changes can be realized through the compressibility of the rubber strip.4)The composite beam steel plate beam manufacturing alignment should be“dead load+1/2 live load”reverse arch superposition bridge longitudinal slope generated vertical alignment,and should consider the impact of erection construction conditions on the bridge alignment;In order to realize the standardized manufacturing,the curve vector height of steel plate beam manufacturing segment is small,so it is appropriate to adopt the scheme of“replacing the curve with the straight curve”.The precision relationship between steel structure members and concrete prefabricated parts should be considered in the design of composite beam anti-collision guardrail.5)The steel bridge should be reasonably set up welding joints according to the need to minimize the damage caused by excessive welding,for the partial penetration fillet weld with penetration requirements should make clear requirements.6)The weathering steel bridge design needs to pay attention to the details of the bridge deck waterproof,beam body ventilation,support protection and so on,at the same time according to the environment of the bridge to determine the coating or coating free use.7)The conventional span bridge has the characteristics of long line and complex linear shape,so the design mode of“general drawing+special drawing”can be adopted.In order to ensure the accuracy of bridge linear shape and connection relation of components in the transformation process of construction detail drawing,it is crucial to select a reasonable detail drawing transformation mode.The detail treatment of steel structure bridge described in this paper has a strong guiding significance for improving the disjunction between the design and manufacture of steel structure bridge and enhancing the level of detail treatment of steel structure bridge designers in China,and also provides reference for the design and manufacture of similar steel structure bridge.