Applied Mechanics and Materials Vols. 357-360

Abstract: This thesis analyses on current situation of the concealed work on the basis of the practical research, concludes the mainly attention aspects and more practical solving methods of Chinese concealed works in the three stages. Finally the development directions of the concealed work are proposed.

Abstract: With the development of the construction work, the quality of construction works is concerned by more and more people. People are increasingly aware of the quality of the project, which is the core of the building works, related to the safety of life and property related to the construction business survival and development. This requires strict control of the quality of building construction, especially for the quality control of key parts of the construction work even more critical. To do this, select the control point of the key parts of the construction works, construction quality control methods and measures for key positions, from the quality control point in addition to meet the quality control requirements in accordance with the general site construction when elaborated higher requirements need its special control measures.

Abstract: This article introduces one new measurement technology for evaluation of the early age shrinkage performance of concrete material without constraint conditions. Its exercise of eddy current method could make the airport pavement concrete material tested accurately during concrete early-age from pouring, when the pavement concrete does not harden. It also can evaluate the effects of the influencing factors on the concrete early-age shrinkage, such as fly ash, admixture, and fiber. By this method, the Shrinkage performance of different concrete material can be evaluated when concrete property design for airport pavement is making.

Abstract: Continuous wavelet transformation is made to identify the parameters of damped harmonic forced vibration Duffing system. With the aid of conversion relationship between the scale and frequency, the solution of nonlinear Duffing equation is adopted by average method, which gained approximate analytical expression for instantaneous amplitude and instantaneous frequency of the system. The nonlinear stiffness coefficient and natural frequency can be gained by least square method and the relationship between recognition accuracy and parameter selection are summarized in the article. Parameter identification method of harmonic forced vibration system is proposed in this paper. Studying the wavelet ridge and corresponding scale by segments to filter out the affects of the simple harmonic motion, to extract systems free vibration signal and to achieve the goal of identifying system parameters.

Abstract: As a convenient and rapid nondestructive testing method, transient Rayleigh wave has an increasingly wide range of applications in engineering, and the testing result is increasingly accepted in the engineering domain. With engineering examples, this article mainly analyzed the nondestructive testing principle and detected the data processing method. By analyzing the engineering example that using transient Rayleigh wave method to detect the effect of dynamic compaction about foundation, the conclusion that transient Rayleigh wave could conveniently and rapidly detect the effect of dynamic compaction about roadbed of the expressway was farther proved, which has certain provide engineering significance for the future engineering detection.

Abstract: In order to improve the construction quality of bridge bored pile, combined with the construction experience of the bored pile, bored pile construction management from two aspects and accident treatment are analyzed in detail, gives the method of many useful suggestions and accident treatment, for your reference.

Abstract: When fire,the fire water supply equipment ofen will not operate. Because the fire pump can not normally water or its pipeline may get rusty To solve this problem, the study analyzed the fire intelligent inspection system;and comparative analyzed the problems of intelligent inspection system and labor inspection. Fire water supply equipment plays a very important role in the fire protection system,so the fire intelligent inspection system is a necessary configuration of the fire extinguishing system.

Abstract: High pressure jet grouting piles have a wide range of application in the engineering field. However, nowadays the increasing construction depth leads to an increasing difficulty of construction,which involves that the quality of construction is much more difficult to control. In this paper, some examples are given of the Luoyuan ultra-deep high pressure jet grouting piles. These examples are described with the used construction quality control methods and preventive recommendations for work construction quality detection methods. That is why this paper has an important guiding significance for similar projects.

Abstract: Under the influence of various factors, considerable number of the sluices get diseases affecting the safe operation. By on-site test of a Yellow River sluice, this article summed up the presence of the disease of the concrete structure, and analysis the reason causing these diseases and put forward appropriate treatment measures.

Abstract: With the further study on the exploration and development of oil fields,some oil fields have gone into the later period for developing gradually. The problems of oil pipeline are more and more prominent. Earthquakes have occurred frequently in recent years. So it is particularly important to study on the seismic performance of corrosive pipeline. Due to the length of pipeline, the geological condition is more complicated, the same pipeline across the site category may have a big distinction. The software of ANSYS was used in this paper to study pipelines with corrosion defects in different site types. The seismic response were calculated, thus various types of site conditions of the velocity, displacement and acceleration time-history response were obtained, and the results were compared and analyzed.