Response of carbon fiber trapezoidal corrugated sandwich structure under air explosion loading北大核心CSCD

The effects of the thickness of the face plate, angle of the wall plate and height of the core layer on the anti-explosion performance of carbon fiber reinforced composite trapezoidal corrugated sandwich structures were investigated. [Methods]First, based on the 3D Hashin failure criterion, a subroutine module of the damage evolution of fiber reinforced composites is developed using the VUMAT user subroutine interface in ABAQUS. Second, through comparison with experiments in the public literature, the effectiveness of the dynamic response simulation method of carbon fiber reinforced composites based on a development subroutine under explosion impact loading is verified. Finally, a parametric study on the explosion resistance of carbon fiber reinforced composite trapezoidal corrugated plates is carried out based on the numerical method. [Results]The results show that, compared with increasing the thickness of the blast face panel, increasing the thickness of the back blast face panel can improve the explosion resistance of the sandwich plate more obviously; when the folding angle of the core wall plate decreases from 45° to 30°, the explosion resistance increases by 1.3%; when it decreases from 60° to 45°, the explosion resistance increases by 6.3%; and whenthecoreheightincreasesfrom8mmto20mm, theexplosionresistanceincreasesby27.7%.[Conclusions]The results of this study can provide references for the explosion-proof design of carbon fiber reinforced composite sandwich structures. © 2023 Journal of Nanjing Agricultural University. All rights reserved.     

《国际船舶压载水和沉积物控制与管理公约》履约对策研究

《国际船舶压载水和沉积物控制与管理公约》的即将生效实施将有效地控制和防止船舶压载水传播有害水生物和病原体。文中论述了公约的主要内容和特点,并就公约对我国产生的主要影响进行分析,最后提出相应的履约对策及建议。     

Analysis of Coastal Wetland Changes Using the “DPSIR” Model: A Case Study in Xiamen,China

Over the past several decades, human activities have had significant impacts on coastal wetlands worldwide. Here, using a model of “Drivers-Pressures-State-Impacts-Responses (DPSIR)” and data collected from coastal wetlands in Xiamen, China, we have analyzed temporal changes in regional coastal wetland ecosystem structure and function from 1950 through 2005. The study period was divided into four parts for comparative analysis: pre-1980s, 1980s, 1990s, and 2000 to present. Our results show that anthropogenic drivers of coastal wetland degradation in this region have increased substantially since 1950, and that this is correlated with a decline in coastal wetland function over the same period.     

Traffic impact analysis of inspection area site selection at a foreign trade container terminal

ABSTRACT

To improve the security and efficiency of terminal operations, a key issue for land area layout at a foreign trade container terminal is to plan and design an inspection area. Since it directly affects terminal traffic, while determining inspection area site selection, we should pay a great attention to operations and management of terminal traffic as well as container inspection. This paper employs a system decomposition technique to develop an integrated simulation framework, which enables us to flexibly obtain the whole picture of terminal traffic conditions and evaluate traffic impacts of inspection area site selection. A real-world terminal with typical patterns of land area layout is chosen to carry out a case study, which shows that traffic flow is unevenly distributed on the terminal road network and that the distribution is influenced by truck streams at the terminal. New findings also include: (1) traffic volume at the terminal apron is rather unbalanced in association with the non-continuous utilization of berths; (2) a proper inspection area should be located near the gate if the terminal conditions permit from the perspective of terminal traffic. This work may provide a decision-making reference for the planning and construction of foreign trade container terminals.     

基于道路服务水平可靠性的交通影响范围确定方法的研究

把道路服务水平引入交通影响范围确定中,对已有的烟羽模型法进行改进,实例检验结果表明：这种改进烟羽模型法具有较强的实用价值。     

旧水泥混凝土板破碎技术研究

水泥混凝土板破碎是旧水泥混凝土路面改造的一项新技术,具有很好的推广应用价值。因此,以水泥混凝土板破碎技术为研究对象,对常用破碎技术进行对比分析,并对破碎施工中的控制要点进行重点研究,可以更好地指导工程实践。     

冲击压实施工对路旁地下光缆影响的实验分析

为了研究冲击压实施工对路侧地下光缆的影响,以广东省道S249线坪乳公路大修改造工程为依托,首先对冲击压实处理旧水泥混凝土路面的作用机理及振动影响、通讯光缆的特性及铺设情况加以介绍;然后就冲击压实施工对道路两侧土路肩埋设的光缆的影响情况及所采取的保护措施进行阐述;最后通过现场检测证实了所采取的避让及保护措施是有效的,不会影响光缆的正常通讯。     

张石高速公路保定段建设阶段其他工程对环境的影响分析研究

项目施工环境保护应贯彻“预防为主、防治结合、综合治理”的原则,树立“原始的就是最美的,不破坏就是最好的保护。力求施工中最小程度的破坏、施工后最大限度的恢复”的环保理念。     

住宅项目交通影响评价系统研究

住宅区是人们每天出行生活的起点和终点,是城市重要的交通发生源。基于地理信息系统（GIS）构建交通影响评价系统,对于分析项目对周边路网的影响,确定项目可行性具有重要意义。本文通过分析住宅项目的交通特性确定了住宅项目交通影响评价系统中交通需求预测方法,详细阐述了系统的工作流程和设计功能,并对实际项目进行了交通影响程度的定量化评价,验证了系统的可行性。     

AS-X树脂的增韧及耐候性研究

用马来酸酐MAH熔融接枝POE制得POE-g-MAH,用其作为AS与POE的相容剂,提高AS树脂韧性与耐候性,并研究了PE-g-MAH和PP-g-MAH作为相容剂PC/AS共混物的增韧作用.用摆锤式冲击试验机、拉伸试验机测试增韧效果,用SEM,FTIR,DSC等测试手段研究产物及共混物的共组成、相容性、相结构、热稳定性.结果表明：PC/AS共混物增韧效果比POE-g-MAH/AS好,PC/AS共混物缺口冲击强度达到5.45 J/m2几乎是纯AS树脂（1.2 kJ/m2）的5倍.