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The steel-structured corridor project of the Industry Innovation Park (IIP) in Beijing adopts an overhanging design with a large size and span. In the demolition stage of the overhanging support, the steel structures will deform. In order to understand the deformation degree of the steel structures in IIP in real time and ensure construction safety, it is necessary to monitor the deformation process of the steel structures. We select the points sensitive to deformation and key parts of the steel structures as monitoring points, and make an automatic deformation monitoring scheme. We use the deformation monitoring system based on measuring robots and Global Navigation Satellite Systems (GNSS) to monitor the steel structures. Then we compare and analyze the deflection values measured by the two monitoring systems. The results from the two monitoring systems are relatively consistent and mutually verify. The results also show that the steel structures are obviously deformed due to the influence of unloading construction. In addition, deflection values obtained by deformation monitoring are compared with the deformation limit of the key steel components derived from the design code. The results show that the deflection values are within a reasonable range, indicating that the construction design of the steel structures in IIP is reasonable and the steel structures are in safe conditions. The deformation monitoring systems based on measuring robots and GNSS technology used in this paper meet the monitoring requirements in the construction phase and can play their value in similar projects.

The quality of the pile head is the construction controlling difficulty of the concrete cast-in-place pile technology when the bored piles, especially the deep foundation piles, are filled with underwater concrete. The hammer method and volume estimation method are widely used to control concrete over filling in the prior technology. However, in the actual operation, these two methods are inclined to cause misjudgment by the field technicians, so it is difficult to accurately determine the height of the concrete, resulting in the under or over height of the pile head, which seriously affect the construction quality and greatly increase engineering costs in construction sites. In order to solve this problem, based on the principle that the mud density of the bored pile and the concrete density are different, and the pressure difference is generated at a certain depth, in this paper a liquid pressure sensor, da-ta acquisition module, wireless communication module, remote network server and monitoring terminal were used to develop an overfilling control-ling device for underwater concrete bored piles. Several engineering field tests were carried out and the test results showed that the device could accurately monitor the timing when concrete reaches the designed pile top elevation position and the specific quantitative height in the underwater pouring process, and can alarm after exceeding the limit as while. The method is simple and practical, and has high promotion value.