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Cao H.,Hongkong Zhuhai Macao Bridge Authority
1st CCPS Asia-Pacific Conference on Process Safety 2013, APCPS 2013

This paper introduces the integrated HSE (Health, Safety and Environment) management model adopted by the owner of the Hong Kong-Zhuhai-Macao Bridge during its construction, including the preliminary work before this creative adoption, the main content as well as the performance of this model. Considering the satisfying operation status indicated by the monitoring data, the author advocates that the HSE management model being applied in major infrastructure construction. © Copyright (2013) By AIChE. All rights reserved. Source

Su Z.,Hongkong Zhuhai Macao Bridge Authority | He C.,Southwest Jiaotong University
Modern Tunnelling Technology

The mechanical mechanism of a fabricated shield tunnel segment lining with longitudinal deformation is rather complex, and it is often difficult to determine the values of the longitudinal loads because of the structure/ground interaction. At present, the segment's additional internal forces, joint bolt forces and joint openings cannot be directly calculated by the common longitudinal elastic foundation beam model or the three-dimensional homogeneous shell model. In this paper, based on a longitudinal shell-spring-contact FEM model, the additional 3D internal forces and deformations after the longitudinal deformation of a shield tunnel are analyzed by a forced displacement method. The calculation results indicate that longitudinal deformation of a shield tunnel causes not only additional longitudinal internal forces, but also a certain transverse deformation and additional transverse internal forces; main bending zones and shearing zones occur along the longitudinal direction; concrete stress concentration occurs near the areas with large longitudinal internal bolt forces. © 2015, Editorial Office of "Modern Tunnelling Technology". All right reserved. Source

Ma N.-J.,South China University of Technology | Wang R.-H.,South China University of Technology | Han Q.,South China University of Technology | Li P.-J.,South China University of Technology | Piao L.,Hongkong Zhuhai Macao Bridge Authority
Zhongguo Gonglu Xuebao/China Journal of Highway and Transport

Based on energy principle, the local vibration of orthotropic steel bridge decks was studied. The orthotropic steel bridge deck was considered to be a stiffened plate. Both longitudinal stiffeners and transverse diaphragms were considered to be beam elements according to the equivalent principle of mass and rigidity. Besides, the plate was analyzed with classic thin plate theory. The mode shape functions were expressed by the product of two independent beam functions. During the deviation of frequency equation, eccentricity and torsion of stiffeners were considered, as well as the membrane strain energy of the plate. A stiffened plate with three classical boundary conditions was studied. The results show that the method proposed is in good agreement with the software ANSYS. The eccentricity of stiffeners has a significant influence on lower frequencies, while the torsional rigidity of stiffeners has a significant influence on higher frequencies, and the equivalent orthotropic plate method is not appropriate to compute high frequencies. Source

Wang Z.-T.,CAS Wuhan Institute of Hydrobiology | Wang Z.-T.,University of Chinese Academy of Sciences | Wang Z.-T.,Hawaii Institute of Marine Biology | Nachtigall P.E.,Hawaii Institute of Marine Biology | And 7 more authors.

A growing demand for sustainable energy has led to an increase in construction of offshore windfarms. Guishan windmill farm will be constructed in the Pearl River Estuary, China, which sustains the world's largest known population of Indo-Pacific humpback dolphins (Sousa chinensis). Dolphin conservation is an urgent issue in this region. By using passive acoustic monitoring, a baseline distribution of data on this species in the Pearl River Estuary during pre-construction period had been collected. Dolphin biosonar detection and its diel, lunar, seasonal and tidal patterns were examined using a Generalized Linear Model. Significant higher echolocation detections at night than during the day, in winter-spring than in summer-autumn, at high tide than at flood tide were recognized. Significant higher echolocation detections during the new moon were recognized at night time. The diel, lunar and seasonal patterns for the echolocation encounter duration also significantly varied. These patterns could be due to the spatial-temporal variability of dolphin prey and illumination conditions. The baseline information will be useful for driving further effective action on the conservation of this species and in facilitating later assessments of the effects of the offshore windfarm on the dolphins by comparing the baseline to post construction and post mitigation efforts. © 2015 Wang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Source

Wang Z.,CAS Wuhan Institute of Hydrobiology | Wang Z.,University of Chinese Academy of Sciences | Wang Z.,Hawaii Institute of Marine Biology | Wu Y.,Sun Yat Sen University | And 5 more authors.

Anthropogenic noise in aquatic environments is a worldwide concern due to its potential adverse effects on the environment and aquatic life. The Hongkong-Zhuhai-Macao Bridge is currently under construction in the Pearl River Estuary, a hot spot for the Indo-Pacific humpbacked dolphin (Sousa chinensis) in China. The OCTA-KONG, the world's largest vibration hammer, is being used during this construction project to drive or extract steel shell piles 22 m in diameter. This activity poses a substantial threat to marine mammals, and an environmental assessment is critically needed. The underwater acoustic properties of the OCTA-KONG were analyzed, and the potential impacts of the underwater acoustic energy on Sousa, including auditory masking and physiological impacts, were assessed. The fundamental frequency of the OCTA-KONG vibration ranged from 15 Hz to 16 Hz, and the noise increments were below 20 kHz, with a dominant frequency and energy below 10 kHz. The resulting sounds are most likely detectable by Sousa over distances of up to 3.5 km from the source. Although Sousa clicks do not appear to be adversely affected, Sousa whistles are susceptible to auditory masking, which may negatively impact this species' social life. Therefore, a safety zone with a radius of 500 m is proposed. Although the zero-to-peak source level (SL) of the OCTA-KONG was lower than the physiological damage level, the maximum root-mean-square SL exceeded the cetacean safety exposure level on several occasions. Moreover, the majority of the unweighted cumulative source sound exposure levels (SSELs) and the cetacean auditory weighted cumulative SSELs exceeded the acoustic threshold levels for the onset of temporary threshold shift, a type of potentially recoverable auditory damage resulting from prolonged sound exposure. These findings may aid in the identification and design of appropriate mitigation methods, such as the use of air bubble curtains, "soft start" and "power down" techniques. © 2014 Wang et al. Source

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