Yi Y.Y.,China Institute of Technology |
Liu G.H.,SinoHydro Bureau 8 Co. |
Zhang Y.P.,China Institute of Technology |
Luo Z.Y.,China Institute of Technology |
Xu L.,China Institute of Technology
Materials Science Forum | Year: 2015
A-TIG welding is a new variant of high-efficiency TIG weld technology, the weld penetration can be improved by using surface activating fluxes. In the present work, 12 mm thick stainless steel plates were welded by A-TIG method utilizing self-developed oxide-based composite activating flux. Results showed that for 12 mm thick stainless steel plates, weld joint of full penetration and one-side welding with back formation and good weld appearance could be achieved by A-TIG welding. Furthermore, compared with traditional TIG welding, the microstructure of A-TIG weld was finer, directivity of dendritic crystals near weld bond line was weaker, and mechanical properties of weld joints was also superior. © (2015) Trans Tech Publications, Switzerland.
Du L.,Tsinghua University |
Tang W.,Tsinghua University |
Liu C.,Tsinghua University |
Wang S.,Tsinghua University |
And 4 more authors.
International Journal of Project Management | Year: 2016
The engineer-procure-construct (EPC) approach has been increasingly adopted in international markets, in which contractors need to have adequate capabilities in effectively dealing with a wide range of risks in a complex environment that consists of various stakeholders. Many researchers have embraced the strategy of partnering to integrate diverse project delivery activities by meeting the needs of all project participants. However, limited research has addressed the cause-effect relationships among partnering, risk management, and organizational capability on how performance improvements can be generated from them on a holistic view. This study systematically investigates the causal relationships among these themes by establishing and testing a conceptual model. With the support of data collected from Chinese contractors with experience in delivering EPC projects by questionnaire, interview, and a case study, the results provide empirical evidences on contractors' partnering application degree, strength, and weakness of organizational capabilities, overall picture of risk management, and project performance level, which form a sound basis for contractors' decision making during project implementation. This study further reveals that partnering can not only directly facilitate organizational capability and risk management but also exert its influence on risk management through enhanced organizational capability, thereby improving project performance. The above insights suggest research and practical emphases on combining risk management with partnering principles to assist in both intra- and inter-organizational activities, and contractors' appropriate linking with involved stakeholders to obtain necessary resources and effectively transfer them for successfully delivering international EPC projects. © 2015 Elsevier Ltd and Association for Project Management and the International Project Management Association.
Liu C.,Tsinghua University |
Huang M.,Sinohydro Bureau 8 Co. |
Tang W.,Tsinghua University |
An X.,Tsinghua University
Qinghua Daxue Xuebao/Journal of Tsinghua University | Year: 2013
Currently, there is a need to study the core competencies of international contractors based on partnering approach to integrate the resources of business chains in international markets. The perspectives of partnering capabilities for acquiring resources, transforming resources, learning and innovation are combined in a partnering-based core competency model to analyze the evolving international contractors' core competencies. Data collected by questionnaire from international contractors was analyzed using correlation analyses, hierarchy cluster analyses and other typical analyses. The results qualify the relationships among all the factors. Then, the partnering-based core competence model was confirmed by an empirical study. The results show the mechanisms that influence on core competencies. Finally, the ways to improve the core competencies of Chinese international contractors has been proposed.
Lin P.,Tsinghua University |
Zhu X.,Tsinghua University |
Li Q.,Tsinghua University |
Liu H.,University of Tasmania |
Yu Y.,SinoHydro bureau 8 Co.
Rock Mechanics and Rock Engineering | Year: 2015
A grouting model is developed for use during the grouting of the complex foundation of a super high arch dam. The purpose as to determine the optimal grouting timing and appropriate grouting pressure involved in controlling the uplift deformation of the dam. The model determines the optimal grouting time as the height of the arch dam increases with the concrete pouring, by checking the tensile stresses in the dam against standard specifications. The appropriate grouting pressures are given on the basis of the actual grouting pressures monitored during the upstream riverbed foundation grouting. An engineering procedure, applying the model, was then proposed and used during foundation grouting under the toe block of the Xiluodu super high-arch dam in south-western China. The quality of the foundation grouting was evaluated against the results from pressurized water permeability tests, acoustic wave velocity tests, elastic modulus tests and panoramic photographing of the rockmass on completion of the foundation grouting. The results indicated that the proposed grouting model can be applied to effectively reduce the uplift deformation and associated cracking risk for super high arch dams, and it can be concluded that the proposed engineering grouting procedure is a valuable tool for improving foundation grouting under the toe blocks of a super high arch dam. © 2015 Springer-Verlag Wien
Wang T.,Tsinghua University |
Tang W.,Tsinghua University |
Qi D.,Tsinghua University |
Shen W.,Tsinghua University |
Huang M.,Sinohydro Bureau 8 Co.
Journal of Construction Engineering and Management | Year: 2016
The engineering-procurement-construction (EPC) approach has been increasingly adopted in competitive international markets, in which design management is critical to project performances. Existing studies have embraced a partnering strategy to integrate stakeholders' diverse expertise and need for better solutions to design. This study has quantitatively investigated the cause-effect relationships among partnering, design management, and project outcomes by developing and testing a conceptual model. With the support of data collected from Chinese construction companies as EPC contractors, this study reveals that contractors' design management should focus on four factors: planning and executing, resolving disputes, optimizing design, and promoting techniques. Path analysis confirms that partnering can not only significantly facilitate design management, thereby improving project outcomes, but also directly promote project performances and create long-term strategic benefits. Canonical correlation analysis further quantifies the different extents to which two groups of partnering critical success factors (CSFs) interact with four design management factors, together with their effects on five indicators of project outcomes. This research has important primary contributions to the body of knowledge by establishing interdisciplinary linkages among knowledge areas of partnering, design management and international project delivery, demonstrating the multiorganizational dynamics in delivering international EPC projects on a holistic view. Understanding the in-depth underlying causes to improve design management will be crucial for EPC contractors to optimally integrate all stakeholders' resources into designs by considering project lifecycle processes. © 2015 American Society of Civil Engineers.
Li B.,Central South University |
Li B.,National University of Defense Technology |
Chen Z.,PLA University of Science and Technology |
Chen Z.,National University of Defense Technology |
And 2 more authors.
Journal of Information and Computational Science | Year: 2013
Based on shaped charge technology, the method of linear cracks of directional fracture in rocks controlled blasting by shaped charge and the elliptical bipolar linear shaped charge with low detonation velocity explosive was presented in this paper. The stress testing experiment was carried on by the stress sensor for analyzing the characters of cumulative pre-splitting of the shaped charge. A numerical calculation scheme for simulating the formation and movement of jet was developed based on the ansys/ls-dyna. The damage of the concrete target penetrated by the jet was showed in the numerical simulation. The results of experiment and the simulation indicted that the shaped charge can form good effect on cumulative energy and produce good pre-splitting blasting effect. At the same time, the safe, economic and environmental benefits had been clearly made. © 2013 Binary Information Press.
Zeng F.,Sinohydro Bureau 8 Co.
Advances in Science and Technology of Water Resources | Year: 2013
The Zhuyin Reservoir is located in the Pearl River Delta. With regard to the technical difficulties in excavation and support of the foundation pit with deep and thick mud, anti-seepage treatment of a deep foundation pit, construction long rainy season, adjustment of water content of dam materials, as well as quality testing and control during its construction, some countermeasures such as excavation by replacing the thin unqualified layer with backfilling materials, stabilization of the slope by squeezing silt with riprap, foundation treatment at the dam site, rapid filling of an earth dam over the long rainy season, and quick quality tests have been adopted. The project achieves continuous and quick construction, and the filling work for the dam was completed within 12 months. The construction quality is satisfactory.
Li X.,Hubei Engineering University |
Wang B.,Changjiang Institute of Survey Planning Design and Research |
Zhou G.,Sinohydro Bureau 8 Co.
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2012
Deeply buried underground engineering often faced with a high geostress environment. Based on the research of the conception of "deep stratum" and "deep engineering", through collecting about 600 groups of the measured geostress data in deep rocks of China mainland, the distribution of the vertical stress, the largest horizontal principal stress, the minimum horizontal principal stress and the lateral pressure coefficient varying with depth in Chinese mainland are shown in this paper. The features of the geostress in deep rocks are elementarily analysed refer to the analysis method of Hoek and Brown, the distribution rule of the vertical stress, the maximum and the minimum horizontal principal stresses with depth in deep stratum are regressive analysed, and trend of the lateral pressure coefficient with depth is also discussed.