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Superfine cement is an ideal grouting material of high-performance ultrafine particles. It has excellent permeability, higher strength and durability. One of the most important features of superfine cement is no pollution on environment. SHD and SCC are two kinds of cement which have different performance. Comparing particle size, initial setting time, compressive strength and plug rate of two kinds of superfine cement by experiment. The result of experiment shows that cement SCC has higher compressive strength and plug rate at higher temperatures.

The yield surface of section axial force and bending moment (AFBM) is formulated by section assemblage concept. Based on flexibility method , a novel planar beam- column element is proposed using yield surface of section AFBM. Dynamic elastoplastic analysis is carried out on a planar steel frame. The results show that the accuracy of proposed model is close to fiber model, and hence it can be used for dynamic elastoplastic analysis of frame structures.

Stability of implicit midpoint algorithm applied to solving the equation of motion with nonlinear damping. The analytical and numerical study exhibit the unconditional stability of implicit midpoint scheme for nonlinear damping systems. The work of the present paper provides theoretic base for further application of this implicit midpoint approach.

This paper introduces an automatic ultrasonic wall thickness measurement system, which adopts the way that the tube billet is partially immersed in the water during the measurement, applied in wall abrasive grinding of nuclear fuel encrust tube billet. Meanwhile, the main components of the measurement system, as well as their characters and functions, are addressed. What’s more, the analysis of the factors, which influencing the system stability and measuring reliability, are also conducted, coupling with the system stability and measuring reliability demonstration.

A highly efficient precision grinding method was proposed for the development of Zr-4 alloy used in nuclear industry. The key techniques to develop this new grinding machine are presented in detail, including soft grinding wheel head, ultrasonic thickness measurement system. An automatic polishing and grinding system was built, which is based on ultrasonic thickness measurement technology. According to a lot of grinding experiments, reasonable, accurate and efficient Zr-4 Alloy grinding parameters was determined. The experiments show that when the line speed of belt is about 18 m/s; the workpiece feed rate is 1000mm/min; grinding head cylinder pressure is 0.12Mpa, the silicon carbide abrasive belt of P80 particle size can get 0.02mm grinding amount and achieve excellent grinding effect.

In order to guarantee the safe operation of train and improve the operation efficiency, a kind of failure-safety control strategy of system is proposed based on the dual-redundant control mechanism. The paper analyzes the function requirement of train automatic speed control, researches on the design principles and methods of the architecture design of the dual-redundant control system which is based on the tolerance theory, analyzes the control strategy of the system running state translation, uses Markov model to analyze the system reliability and safety. Finally, a series of simulation analysis are performed, and the results show that the system has good reliability.

Miscibility of ternary polymer blends composed of poly(ethyleneimine) (PEI), poly(ethylene glycol) (PEG), and carboxymethyl chitosan (CMCS) was investigated by dilute-solution viscometry, FTIR spectrum, and scanning electron microscope (SEM) techniques. The results of these measurements indicate that PEG is immiscible in the ternary CMCS/PEI/PEG polymer blend.

To improve the efficiency of the automatic control in the process of train operation, reduce state transition caused by the signal interference and guarantee the safe operation of automatic train operation system, a kind of train automatic speed control strategy based on the fuzzy-predictive control algorithm is put forward. According to the dual-redundant control model, the reliability and safety of the train automatic speed control system is analyzed. Using anti-interference design, a series of model simulations have been accomplished. The results show that the system has good reliability.

An electrode coating slag system CaO-CaF2-BaO-TiO2-SiO2 has been designed after analyzing several domestic and abroad basic slag system. In view of uniform design method and computer program, the experiments were arranged. Nine to eleven coating components were taken as independent variables and they were divided into five levels in all twenty-nine experiments. Four mechanical properties and diffusible hydrogen content of weld deposited metal were taken as target functions. The data were analyzed with mathematical and statistic software. The results give the influencing trend figures of coating components on mechanical properties and diffusible hydrogen content and interrelation multinomial mathematic models between independent variables and functions. With these trend figures and mathematic models, the adjusting direction of improving mechanical properties and decreasing diffusible hydrogen content of weld deposited metal can be inquired, and target functions optimization searching have been done.