Applied Mechanics and Materials Vols. 94-96

Abstract: The increasing scarcity of modified asphalt is affected by storage stability at the present , then the preparation of high strength bituminous mixture gradually become a trend which adopted by hard asphalt of low-grade . This paper determines appropriate mix through the laboratory tests for hard asphalt which was verified in the trial section proves that the desire for load performance in highway engineering can be satisfied with this asphalt type.

Abstract: Delays in construction projects are usually inevitable, and most projects are not completed on time. The scope of this study was to find out the factors that are responsible for minimizing delays on construction projects in Islamic Azad University (IAU) Shoushtar Branch in Iran. The overall ranking of most vital factors causing delay and how they cause it, as well as effective methods of minimizing delay on construction projects was obtained by the mean rank score. It was found that the use of experienced contractors and subcontractors, financial difficulties by contractor and change orders by employer during constructionwere some of the factors responsible for delay. However, time and cost overrun were seen to be the major factors causing delay. The result showed that the use of experienced contractors and subcontractors, accurate initial cost estimates and clear objective and scope were effective methods of minimizing delay on construction projects. The results obtained here, though peculiar to a certain area can be adopted for other case studies in which similar problems are encountered.

Abstract: Facing the questions of the global climate change and energy shortages and other issues, the low-carbon economic development model which based on the low power consumption, low pollution, and low-carbon emission is paid attention by more and more enterprises. This paper based on the low-carbon economic development model to analyze the present structure’s status of the real estate industry and look forward to real estate developments. By analysis the factors of constraints in low-carbon real estate development from the policies and regulations, market orientation and other aspects, and puts forward several suggestions on structure optimization of the real estate industry.

Abstract: For the large cascaded hydropower stations, an electricity pricing mechanism of cascade hydropower stations on large basins is proposed. The main idea is that the electricity generated by different hydropower stations on the same river can be sold to the Grid Corporation with the same price. Using five hydropower stations on the middle and lower reaches of some river in China's south-western region as a case, the pricing methods based on the Operation-period pricing method are studied. The changes of hydropower stations' earnings are analyzed through the cascade hydropower stations optimal scheduling model and simulation analysis. The results show that the mechanism is conducive to hydropower development and the comprehensive utilization of water resources, which provides an alternative of electricity market reform strategy for the national energy departments.

Abstract: Based on three bridge dismantlement, duct grouting density of prestressing tendons was investigated in-situ . The indices were analyzed statistically to find out the construction quality of PC box-girders in China. The investigation result indicated that the duct of prestressing tendons were only partially grouted, with over 50% ungrouted for longitudinal tendons and over 70% ungrouted for transverse tendons. Obviously, this increased the prestress loss in the tendons. The quantitative indices proposed in the paper is helpful in understanding the underlying reason for cracking and over flexing in the PC box girder ,and it also provided the important basis for structural analysis of PC box-girders.

Abstract: The green house can save resources and harmonize with nature. The major functions of the green house should be environment-friendly, saving energy and comfort. These functions rely on some key saving energy technology using in the house. Green houses’ cost will be higher than ordinary house because of using saving energy technology. The green houses’ value increase and the cost control may realize through the value engineering analysis.

Abstract: The comfortable housing project for low-income urban residents possess many special characteristics such as large numbers, dispersed distribution, the large-scale of construction, urgent time schedule and strict requirement of high quality. To ensure reasonable period and construction cost, it is also necessary to reform and innovate the way of construction management thinking and working methods. Pre-control measures of construction quality are put with emphasis on transforming passivity supervision into initiative forewarning. Management efficiency of the comfortable housing project can be enhanced. The comfortable housing project for low-income urban residents is built into environmental project taken to develop energy-saving and ground-saving residential in our country. It is a realistic and sharp contradiction that construction enterprises are pursuing profit when indemnificatory housing constructing is weak of profit, and that it is an easily occurred problem that the quality of indemnificatory housing is not security. In this paper, based on the six sigma quality management the Quality Assurance System of indemnificatory housing is put forward, which can be regarded as guidance for construction enterprises.

Abstract: The coal mine safety accident is a significant problem to be faced in our country's coal mine safety management. Facing the increasing situation of coal mine safety production, it is very important to analyze the key risk factors from the every aspect of coal mine production. In this paper, the problem is analyzed by AHP. The analysis result is a very valuable reference for producers because it can provide scientific basis for coal mine safety production decision-making.

Abstract: Combined with Wuhan test section of Wuhan-Guangzhou passenger special line, proportioning of mixtures、integrity of pile、bearing capacity and cushion of CFG pile detection technology were studied in this paper. The systematic and perfect methods of quality detection and control standard have been put forward. It provide useful reference for practical engineering．

Abstract: Based on the data of the extra large diameter and extra distance of drilling of the Shanghai Yangtze Tunnel Highway, the paper introduces various fire scenarios under shield construction, and examines the distribution of various tunnel fires according to the actual circumstance of tunnel construction, patterns of smoke change of various fire circumstances; The thesis also provides significant measures and time for evacuation, and the features of fire expansion and smoke circulation in different fire situations, It compares fire expansion and smoke extension in different fire situations, analyzes patterns of fire expansion and smoke extension in different measures of fire prevention and their impact on the consequences of fire. Meanwhile, the thesis evaluates the effect of fire prevention, and explores some basic principles and safety measures for evacuating performance and fire rescue, crew safety and efficiency according to the temperature in the tunnel, pressure and smoke extension with fire