Operating information-diagnostical system (IDS) BING-3 on the example of Andijan water reservoir

The article provides recommendations on the possibility of implementing an automated system of diagnostical control over the operational condition of a dam. Implementation of BING-3 allows to control the opening of cracks in concrete structures, take readings from piezometers and air temperature sensors in an automatic regime. The article gives an analysis of instruments used for diagnostics and reasons for the failure of certain devices. It has been established that further use of morally out-of-date devices reduces dam safety observation volumes.


Introduction
The majority of earth-fill and concrete dams in the republic were built in the middle of the last century. Correct technical solutions, implemented in the design of these dams, allowed to operate them for over fifty years [1,2]. However, nowadays, the control over the dams is carried out by manual measurements of two or three coordinate crack measurers, pressure and non-pressure piezometers, reverse plumbs [19,20]. Also, earth-fill and concrete structures of hydrosystems have many marks installed, whose positions are controlled relative to reference points using geodetical equipment. Such a system of controlmeasurement instrument management does not meet current requirements [1]. Time requires reequipping of all average and high pressure dams with modern instruments. When implementing automated systems of diagnostical control, several problems of financial origin may come out, including personnel training, etc.
In this article, we consider the issues concerning technical solutions for implementing automated systems of diagnostical control at the Andijan water reservoir (Figure 1).

Fig. 1. Plan view and cross-section view of Andijan water reservoir
The goal of the work is to justify the practicability of implementing the system of diagnostical control over the operational condition of a concrete dam.
The task of improving the control over earth-fill and concrete dam conditions is determined with the necessity of providing the safety of operation of very important and technically complex facilities [3,4,10,11,15].

Methods
The research was carried out using the traditional method of conducting field research of structures.
There is a big experience accumulated throughout the world on implementing automated systems of diagnostical control over the technical condition of dams, for example, BING-3 [7,8,9,13,14]. BING-3 system operates in the automatic regime and carries out control over the opening of cracks in concrete structures, records piezometer and air temperature sensor readings. The system has successfully recommended itself at Orto-Tokoy water reservoir in Kirgizstan, being used since 2014 [13].

Results and Discussion
All the control and measurement equipment listed in table 1 must be replaced in Andijan water reservoir. For measurements of deformations and temperature at the base and in concrete, openings of deformation joints and cracks, measurement of filtration pressure, string and semiconductor transformers of static control, and measurement instrumentation were installed in the dam [1]. The frequency of alternating voltage at transformer outlet or active resistance of semiconductor thermoresistor serves as information parameter of the electrical signal [11,12]. Types of these transformers and their measuring limits are given in Table 2. In 2015 observations by static control measurement instrumentation were carried out every 10 days. Monthly checks of the number of sensors, which transmitted data, showed that their amount has decreased compared to 2014. Table 3 shows data on the number of transformers used to take measurements in 2014-2015 and the decrease of the number of transformers used for observation in December of 2015 compared to June of 2014. It is seen from the given data that the number of transformers used for diagnostics decreased by 9 units in 2015 compared to 2014. The main reason for the reduction of observations is the failure of generator-frequency meter ЦС -5m. This device has morally aged and taken out of production. Frequency meters and period meters produced nowadays don't have the same sensitivity as ЦС -5m. That is why it will be possible to recommence observations with a specified group of devices will be possible only after obtaining secondorder devices with the required sensitivity.
The Diagnostic center receives data from Andijan water reservoir in the form of transformer string oscillation periods (microseconds) or thermoresistor resistance values (Ohm). Measurements on about 1250 transformers are taken in one cycle. 26 measurement cycles are carried out in a year. Work on these data starts with their initial processing, which lies in the conversion of transformer electrical signals into physical values [11]. Depending on the characteristics of the transformer output signal, the physical value being measured is calculated using the following relationships: -logarithmic relationship for thermoresistor transformers У = A/(ln X-B) -273. 15 -parabolic relationship for string transformers Where У is value being measured А, В, С are graduated relationship coefficients Х is transformer output signal. These calculations are carried out for each of 1250 transformers of static control measurement instrumentation. Table 4 with measurement data, carried out in March of 2015 and the results of their initial processing, is given as an example of information obtained from the water reservoir.

Discussion
Principles of building the automated system of diagnostical control over the condition of hydraulic structures (ASDC HS) [13] is in the following ( Figure 3): -ASDC system includes in itself an automated system of sensor query (ASQ CMI) and information-diagnostical system (IDS) BING-3, operating in a common computer network (local or corporate) and integrated at the software level.
-ASQ CMI carries out open-end transfer of data from initial sensors to central data collection server. At the data collection server outlet ASQ SMI is integrated with IDS BING-3. Besides, overall ASDC HS is an "open" type AS, which provides stage-by-stage system development, interchangeability of hardware and software means, and compatibility with ASM of other levels.
-ASQ CMI is a distributed system of remote control, which is built according to "industrial network" technology, which provides reliable protection from interferences, reduction in price, and simplification of works in mounting and operation of automated systems. ASDC HS structurally includes the following elements: -lower level -control-measurement instrumentation (CMI): sensors, measuring devices; -medium level -the system of telecommunication, transformation, and transmitting of information in digital code to central data collection block ASQ CMI; -higher level -program-technical complex, including in itself central automated query block ASQ CMI and information-diagnostic system of control over structure safety (IDS) with corresponding computer hardware and software. At the lower level ASDC directly uses measuring devices with sensors, registering physical processes and impacts on the structure. This automatization system uses water level sensors, sensors of excess pressure in pressure and nonpressure piezometers, discharge meters at drainage wells and measuring weirs, displacement sensors in crack meters, plumbs, string ranges, temperature sensors. The general requirement to sensors is their unified analogue, a digital or radiofrequency outlet of standard type, and interchangeability. Medium level of ASDC HS includes in itself sensor communication means, transformations of the analogue signal into digital codes, and communication lines for signal transmission from sensors to the central block of automated query system ASQ. Data collection modules, located in the maximum concentration of measuring devices, are used to connect sensors to a communication line with an industrial interface.
Higher level of ASDC HS system is a program-technical complex, including data inputoutput controller, central block based on data collection industrial server, base specialized software for management of automated query of sensors and automated work areas with the complex of programs as part of IDS safety control of HS.

Conclusions
The main results of the work consist of the following: 1. Collected and analyzed field observation data from Andijan water reservoir concrete dam indicate of their safe operation at its long operation state. 2. Based on the analysis of available data, the main requirements to hydraulic structure operational control systems were determined, i.e., composition and types of field observations, device control means, observation periodicity, and initial data processing seismic monitoring and registering of earthquakes. 3. Permanent control over CMI operational efficiency in the process of monitoring HS