Multi-point displacement meters are widely used in deformation and displacement monitoring of slope rock mass and cavern rock of water conservancy and hydropower projects, which can realize automatic monitoring and safety warning. The new multi-point displacement meter device introduced in this article is a new structural type different from the old described in DL/T 1272—2013, including an anchor head, a transmission rod (steel pipe) and a plastic protection tube installed with concentric shafts, as well as the orifice mounting base and the matching displacement sensor. Its application range and measurement accuracy are exactly the same as the multi-point displacement meter device, and its technical performance is superior. It has advantages such as high equipment precision, easy installation and high observation accuracy. Moreover, one of its important technical achievements is realization of the dual functions of manual instrument measurement and automatic measurement by displacement sensor, which can be used to verify the automated measurements and realize the continuous observation by use of the manual measurement data during replacement of the displacement sensors.

The automatic monitoring system of Manwan hydropower station has been in operation for 11 years. This paper introduced the main problems in operation. Accordingly, some innovation measures were implemented and good effect was achieved.

This paper focused on the main characteristics and seepage causes of diseased embankment dams. By introduction of the mechanism and effect of some treatment methods, such as grouting and concrete anti-seepage wall, the paper put forward some optimized programs and pointed out the issues that attention should be paid to in construction, for reference.

After years' operation, seepage may occur at earth dams. This paper analysed the types and cause reasons for seepage, and, accordingly, advanced some preferred treatment schemes and issues calling for attention in construction, for reference.

During investigation, design, construction and operation of tunnels, due to constraints and mistakes, failures happen. There are 10 cases at home and abroad presented in this paper, as well as the cause reasons and the lessons learned, for reference.

Discussion was made on fitted line parameter of a sensor by different ways, so as to understand the meanings of the linearity in hydraulic monitoring sensor and the effect of different linearity in measurement using sensor or calibration sensor.

The diversion tunnels of Jinping Ⅱ hydropower station extend across Jinping mountain, including the areas with high stress and high external water pressure. The tunnel section is huge. In order to ensure the long-term and safe operation of the power station, the maintenance channels are arranged for diversion tunnels. This paper introduces the design and structural calculation of the maintenance shaft of emergency gate in water inlet and the access door of construction adit at the head and end of the diversion tunnel.

Based on the theory of beam on elastic foundation, using underground frame structure calculation model, with the coordinate system, load constants of bottom plate, roof and side walls of box culvert below dam as well as shape constant of foundation beam were derived. Further, the internal force and displacement analysis method of dam culvert structure under non-uniform internal water pressure were given. All these results can be applied to the calculation of rectangular underground frame structure.

Under the long-term complex natural condition and the effect of various both inner and outside forces, the state of earth-rock dam is changing momentarily and safety trouble may generate without obvious prewarnings. Especially, because of careless design, poor-quality construction and unsuitable management, security of earth-rock dams built earlier after the country founded have many problems. So it is very significant to give a safety appraisal to existing earth-rock dam for the sequential maintaining and reinforcing work to protect downstream dwellers’ lives and their properties. And this article will take Jinji reservoir and dam of Jingmen City in Hubei province as an example so show the method and content of safety appraisal of earth-rock dam.

Based on design review, the typical problems in design of safety monitoring for small reservoirs were systematically summarized, including inadequate capability of design organization, omission of important design content, incomplete design-related basic information, improper utilization of existing safety monitoring equipment, design divorced from engineering practice, confusing set of important and unimportant monitoring items, and et al. It is proposed that the quality management of safety monitoring needs to be enhanced in aspects such as more attention paid to the design, improvement of guidance and training, strengthening of design inspection, special focus on safety monitoring design of reinforced and newly-built small reservoirs.

As the second largest hydropower station in China, Baihetan hydropower station has a total installed capacity of 16 000 MW. It has the characteristics of high water head, large installed capacity and large HD value. To ensure its safe operation, 38 900 tons of steel were used to make penstocks, including 10 100 tons of 800 MPa high-strength steel. This is the first case where thickness of 800 MPa penstock reaches 68 mm in domestic hydropower industry. By studies on 800 MPa high-strength steel and a large number of tests, it is proved that the use of 800 MPa high-strength steel meets the function requirements of large power stations.

The calculation and analysis of dam break flood is an important basic work for dam risk assessment and emergency management. The size of dam break has a great impact on the calculation of dam break flood. At present, most research on the development of dam break is about earth rock dams, while the research on concrete dam break is less. So in the calculation of dam break flood, the geometric size of concrete dam break is usually assumed based on experience. According to the database of historical concrete dam break cases at home and abroad, combined with structural characteristics of concrete dams, the causes and failure modes of concrete dam break are counted and analyzed, and the general principle for estimating the size of concrete dam break is introduced, which provides a reference for determining the parameters of concrete dam break in flood calculation.

This paper analyzed the error source that effect the GPS-RTK survey accuracy, advanced the RTK point accuracy in anticipation, and it proved the reliability of the accuracy index by actual cases.

Slope protection is an effective measure to improve the dike safety. The traditional slope protection are mainly designed and constructed in the aspects of improving the stability of river bank, preventing the water and soil loss, and flood discharge and drainage in river channel. The slope protection engineering affects the ecological balance to a certain extent, but it is less taken into account. Based on this, the author puts forward the articulated concrete block revetment, which not only meets the basic functions of revetment, but also ensures the integrity of river bank ecology. It is in line with the concept of ecological slope protection. As a new slope protection material, the concrete block can be specially designed according to the needs of projects. And the concrete block revetment has the characteristics of fast implementation, low construction cost and strong stability, which can be widely used in water conservancy projects such as revetments of rivers, lakes and channels.

As time goes by, aging would be found with the concrete dams which can be attributed to physical and chemical reactions.In detail, the integrated elastic modulus and safety margin would decrease and rehabilitation is critical to safety operation.This paper analysed the aging process of concrete dams and discussed their expected life span.