现场预制 meaning in Chinese

site precasting
site prefabrication

A great amount of post tensioned pre - stressing concrete single box beam for double track ( as called the box beam hereinafter ) has been used on the line . it is of infeasibility in adoption of the traditional practice of pre - fabrication in precast factory and erection of the box beam with the track laying machine for that this type of beam is characterized by new structure , complicated workmanship , large volume and difficulty in transportation . therefore , the key and hardest problem to tackle is that what processing should be adopted to precast the box beam on site and that what kind of machinery should be used to transport and erect the box beam
由于该型梁具有结构新、工艺复杂、体积大、运输困难，将常规铁路的桥梁厂制造桥梁、经过铁路运梁到工地、边铺边架进行桥梁制造与架设的传统施工模式应用到该线是行不通的，必须在现场预制桥梁、并采用专门的运架梁设备进行桥梁架设，因此箱梁的制造、架设施工成为该线施工技术攻关的重点和难点。