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The aim of this presentation is to recommend an economical technique for preparing fiber-reinforced mortar for blast resistant structures using polymer fibers. Fiber-reinforced concrete was developed to improve ductility by preventing micro-cracking. It is also used to strengthen blast resistant structures, and to prevent spalling under the fire conditions. Because of the better mechanical properties and bonding performance, metal fiber is mainly used for the blast resistant structure. However, because of the high cost of the fiber, the cost of the reinforced cementitious composite is higher than normal concrete. This is especially true for short steel fiber where its high cost has to be weighed against its outstanding performance. As a solution, a more economical substitute can be found in polymer fibers of nylon and polyvinyl alcohol fibers, which cut costs without a significant decrease in performance. In this study, for fiber-reinforced mortar, each fiber and combination of fibers incorporated made up 1% to the total volume of the mortar. For fresh state properties, although the mortar contained combined fibers, there was no significant decrease in flow and air content. As the polymer fibers were combined with steel fibers, approximately 35% of tensile strength and 12% of flexural strength decreased. However, from the strain-stress relationship, the fiber-reinforced mortar with combined fibers showed more favorable results than single steel fiber. The results of this study are expected to contribute on the economic approach of fiber-reinforced cementitious composites using combined fibers.

To overcome the defect that the support pressure is required to be measured or supposed in elasto-plastic analysis in strain-softening rock mass, by the connection of the support pressure imposed on surrounding rock mass, without assuming the support pressure is known a priori, an improved model of solving plastic radius and the distribution of radial displacement around the circular tunnel is proposed. Based on Hoek-Brown yield criterion, the results obtained by strain-softening model are compared with those of elastic perfectly brittle and elastic perfectly plastic models. The examples reveal that the difference of plastic radius obtained by the three models is comparatively smaller, but the difference of radial displacement is comparatively larger. The proposed model overcomes some defects of the previous studies in deformation analysis for tunnel.

This paper shows a multifunctional and real-time control system of environment and building. It includes wireless data acquisition terminal, wireless ad-hot network module, inspection device, data acquisition gateway, software of energy consumption analysis, system of infrared thermal imaging analysis.

The theoretical calculation of PHC pipe pile negative friction resistance is difficult to obtain valuable results due to many complex factors involved, such as soil properties, consolidation conditions and actual working environment, so the field monitoring is the only feasible method. The pile negative friction resistance can be got by pre-buried sensors inside the pile to monitor the changes of stress and strain of shaft. However, for PHC pipe pile, the sensors can not be embedded and protected effectively in the process of pile manufacturing, which makes the negative friction resistance of PHC pipe pile become a very thorny problem. Based on the improved field monitoring method and data analysis of sliding micrometer technology, a new method was introduced into the PHC pipe pile negative skin friction resistance testing in this paper. We can got not only the PHC pipe pile negative friction resistance, distribution range and neutral point position with different load or time, but also the strain distribution, axial force distribution, skin friction resistance and toe resistance distribution of pile, etc. The practical engineering application shows that the new method is very effective to monitor PHC pipe pile negative friction resistance and very beneficial to further research on formation mechanism and theoretical calculation of negative friction resistance of PHC pipe pile.

Due to the large capacity of large power transformers, normally the power capacity of a load test is difficult to meet the test requirement, which makes the ancillary devices such as induction regulator, intermediate transformer etc. difficult to meet the test demands too. The transformer factories with limited power capacity can only perform load test under less than fifty-percent of the rated load current, which not obeys the standards and technical protocols. Thus, a field load test method for large power transformers is proposed in this paper. It carries out the reactive power compensation with compensation capacitors, which reduces the capacity of test power supply and makes the field load test possible. This method also gives a guarantee for the safe and stable operation of power transformers.

Through the condition analysis of the drill rod during the mining horizontal drilling for gas drainage, the finite element model of the drill rod lateral vibration is established. The drill rod lateral vibration is related to the diameter and length of the drill rod. With the increase of the diameter of the drill rod, the natural frequency of the lateral vibration of the drill rod increases constantly. The increasing amplitude of the natural frequency at the larger diameter of the drill rod is larger than that at the smaller diameter. When the drill rod is longer, the natural frequency of the lateral vibration of the drill rod is lower. From the modal images of the drill rod, the lateral vibration of the drill rod is similar to the sine curve. During the horizontal drilling in coal seam, the drill rod contact and impact with the hole wall which will bring about the fatigue fault of the drill rod and the collapse of the hole wall.

SVC is a dynamic reactive compensator based on switching type HV electrical and electronic devices, well recognized as an effective means of resolving power quality problems. SVC is complex in structure, consisting of TCR valve sets, FC filter channel, etc. In particular, TCR valve set adopts thyristor serial connecting technology, and over 100 thyristors are adopted, which requires real-time status of devices in SVC to be monitored and uploaded, and even failures to be recorded. Therefore, the monitoring software becomes an important part in ensuring SVC safe operation. Combined with actual cases, this paper introduces a technology of using C++ Builder and Inter Base to design the static reactive compensator monitoring software. The user interface is elegant, with short development period, highly transplantable, and easily modified.

This paper presents the basic principle of gas leak ultrasonic produce, the use of ultrasonic transducer array collecting leak ultrasonic signal, the signal filtering and power spectrum estimation of signal processing algorithms, intelligent gas leak detection system is developed. The detector is convenient to use, can realize quick check gas leak, application of virtual instrument for leakage signal analysis and processing, implementation of gas leak detection and estimation of leakage.

The formwork and scaffold leasing companies become one of important links in the industry supply chain. The sustainable development of the company requires the alliance and the further cooperation between the leasing companies. This thesis attempts to study how to decrease the alliance cost and to achieve reasonable cost allocation through linear programming and cooperative games in a sense of transportation cost allocation. Furthermore, the thesis puts forward the data processing method of minimizing the ratio difference of cost saving. Based on this study, it can be concluded that the method is more rational for cost allocation.

Two point incremental forming is proposed to form the thin sheet into the desired shape in this paper. The forming accuracy of two point incremental forming is compared with single point incremental forming for Aluminum 1060. Then the forming accuracy is measured by FARO three coordinates measuring instrument. And a new method is proposed to analyze forming accuracy quantificationally. The experimental results show that the forming accuracy of two point incremental forming is obviously higher than single point incremental forming.

In winter, it is very important to get rid of the ice and accumulated snow which are covered in the road so that it can reduce a series of badly accident. Therefore, a variety of road deicing methods are listed in this paper. The advantages and disadvantages of road deicing methods are analyzed. The article enumerates some inductions to several road deicing devices which are used in the cold areas of our country. The paper gives some reference for road deicing devices research.

A nondestructive inspection system has been developed using the active thermography technology. However the solder defects can not be distinguished directly from the thermal images captured by IR camera because of the heating non-uniformities. The principal component analysis is explored to identify the defects of the solder bumps accurately and effectively. Thermal contrast image is obtained by subtracting source distribution map from the original thermal image. The hot spots corresponding to 16 solder bumps are segmented. The pixels with the thermal contrast values ranging from 0.18°C to 0.20°C are counted, and the maximum and the minimum of the pixel value are found out respectively, which are used in the principal component analysis. The missing bump is identified by the first principal component score. The results show that it is effective using the principal component analysis in active thermography for defects inspection of solder bumps in microelectronic packaging.

This paper presents an investigation of the effect of emulsified waste cooking oil on the porosity, EDEX results and the reduction of autogenous shrinkage of the high strength concrete with W/B of 20% incorporating 20% of fly ash and 10% of silica fume. Two different types of shrinkage reducing agents, the existing glyeol based shrinkage reducing agent (SR) and the waste cooking oil (WCO) were applied and compared. The effect of emulsification of the WCO with two emulsifying speeds, 2000 rpm and 4000 rpm were also investigated. It is found that the emulsified WCO has desirable shrinkage reduction effect than un-emulsified WCO and existing SR. Test results also indicated that emulsified WCO could also reduce pore volume due to saponification reaction