The importance of consistency of VRLA batteries was summarized in this paper.The effects of consistency of batteries on service life were analyzed.The reasons and solutions about consistency of the batteries were discussed,and the effects of several key points during battery assembly process on consistency were also discussed.

Among large-scale dams with high water head in our country,the Laxiwa Hydropower Station is the first project that adopts counter-arched water cushion pool as its downstream energy dissipator.It is also a cushion pool with the shortest length and the narrowest width among the existing extra-high arch dams in China.Its energy dissipation ratio of unit water body ranks the first among ones of its own kind and close to the highest standard of other countries.Designs of counter-arched water cushion pool structure and drainage-pumping system and so on are optimized after a series of research,experimentation and computation without clear provisions of codes and shortage of engineering data.The design experience of counter-arched water cushion pool enriches contents of the downstream energy dissipator for China,but also has important referent value for the design code and other large scale high-head dams.

This article generally introduces the characteristics,ranges for use and developing trends of commonly used lead alloys for lead-acid battery grids.In consideration of environment protection,if only the process control is reasonalbe,it is possible to make high performance products of Pb-Ca-high Sn complex alloys by which Pb-Cd alloys can be replaced.

The water diversion system for the Laxiwa Hydropower Station is arranged in the mountainous body on the right-bank of the Arch Dam.The original intake No.1 & No.2 were designed to be low bottom one and No.1 and No.2 generating units were arranged to be put into generation firstly.The side-slope construction of intake is more difficult than expected one,so that the progress of excavation and support was heavily lagged because of unfavorable terrain and geologic conditions,which affected the excavation progress of right dam abutment and No.1 & No.2 diversion penstocks were installed finally so that the initial power generation time was delayed.In the optimal design,we adjusted the power generation order of units,that is,No.6 and No.5 generating units would be firstly put into generation and optimized the intake arrangement.As a result,the excavation of right dam abutment was completed 20-day ahead of schedule and the contradiction between installation order of penstocks and generation power order in the original design was solved,which could shorten about six months to finish the construction of water diversion system and is significant for generation power ahead of schedule.

This paper analyzes and verifies charge acceptance of VRLA batteries correlated with their discharge capacities and cycle lives,and partially tests and analyzes some aspects in the design and manufacture which have influence on the charge acceptance of batteries.

At present,the hydropower construction at home receives a new development opportunity.It is necessary to grasp well the quality control and design optimization of product in order to guarantee the project quality.The implementation of design-supervision system is a useful exploration.In combination with practice,this paper describes three steps of the construction,design and supervision of the Laxiwa Hydropower Project,the important design optimization advices and the experience of design-supervision work.

Aimed at the difficulty of parameters selecting in tunneling engineering design, the improved H-B criterion which can consider the mechanical properties of rock block and geological condition of rock mass is introduced to the supporting design of a highway tunnel.Based on the detailed description of the using condition and using method of H-B criterion,the mechanical parameters of rock mass are determined when considering and not considering the blasting effect.Furthermore,the numerical analysis considering the construction process is done using the software FINAL.Finally,some key problems in the course of using H-B criterion are discussed.