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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.

Metro shield tunnels have been widely used in Metro construction. The pre-cast concrete segments of shield tunnels are important prefabricated components in the construction of metro shield tunnels. The quality of segments is directly affected the quality of shield tunnels. In the construction process, a large number of precast concrete segments should be installed and some segments should be formed into rings, so manufacture management, carriage management and constructing of precast segments also directly affect the efficiency and quality of construction. Therefore, it is very important to establish an information management system for precast concrete segment through Internet of Things technology. The system would provide manufacture management (including concealed acceptance, quality inspection, and production-inventory), carriage management (including pre-delivery management, transportation tracking) and construction management (including quality inspection, warehousing management, installation management).

Through the Bachu-Jiashi Ms6.8 earthquake liquefaction investigation and test, obtain the 47 the standard penetration test date, examine the existing standard applicability based on standard penetration test of soil liquefaction identification method, and put forward the new sandy soil liquefaction evaluation formula. Analysis shows that the current assessment formula base on SPT counts of soil liquefaction are not applicable to Xinjiang region, will give the risky results. In the new survey data of soil liquefaction evaluation model established of five parameters by the earthquake intensity, the measured SPT counts, datum SPT values, groundwater level, and sand buried depth. The datum SPT values, the influencing coefficients of water and sand depths are gain by a normalized method and by an optimizing method. Establish new formula of soil liquefaction evaluation to the success judging rate is higher, the model shows that constructing reasonable and calculation formula is reliable, can be employed for regional code formulation in Xinjiang area.

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