Survey and alignment design of Shanghai synchrotron radiation facility

The biggest challenge of survey and alignment is the soft groundwork and the tight positioning requirement for Shanghai Synchrotron Radiation Facility. Control network, fiducialization, pre-alignment and installation on site and smoothing are five crucial steps for the installation and alignment process. By utilizing the laser tracker and hydrostatic levelling system, the error budget should be within 0.08 mm for control network and 0.05 mm for the other steps. The expected error budget is 0.12 mm for elements between girders, which is a little smaller than the requirement of 0.15 mm. Besides the target of error control, reliability, efficiency, cost and real-time monitoring are factors considered in the design.