FHWA模式在港口建设项目环评中的应用

运用美国ＦＨＷＡ公路噪声预测模式对秦皇岛新港口建设引起的相关公路两侧垢学环境变化进行了预测。通过预测与实测结果对比,证明了ＦＨＷＡ模式不仅适用于公路建设项目环境影响评价,而且适合于港口建设项目环境影响评价。     

Potential utilization of riverbed sediments by hydrothermal solidification and its hardening mechanism

Hydrothermal solidification of riverbed sediments (silt) has been carried out in a Teflon (PTFE) lined stainless steel hydrothermal apparatus, under saturated steam pressure at 343–473 K for 2–24 h by calcium hydrate introduction. Tobermorite was shown to be the most important strength-producing constituent of the solidified silt. A longer curing time or a higher curing temperature was shown to be favorable to the tobermorite formation, thus promoting strength development; however, overlong curing time (24 h) seemed to affect the strength development negatively. The hardening mechanism consisted of the crystal growth/morphology evolution during the hydrothermal process. The species dissolved from the silt were precipitated first as fine particles, and then some of the particles seemed to build up the rudimental morphology of calcium silicate hydrate (CSH) gel. The CSH gel, with precipitated particles, appeared to cause some reorganization within the matrix, which made the matrix denser and thus gave an initial strength development. Tobermorite, transformed inevitably from the CSH gel, reinforced the matrix with its interlocked structure, and thus further promoted the strength development.     

沈阳市突发性环境污染事故应急监测能力建设现状分析

分析了沈阳市应急监测工作现状,指出了存在的问题,并指明了今后的发展方向。     

Erosion Control at Construction Sites: The Science–Policy Gap

/ To test the effectiveness of Michigan's soil erosion control law, 30 construction sites were evaluated in the east-central part of the state. The analytical framework lumped nine best management practices (BMPs) most closely related to the law into three categories: slope stabilization, soil stabilization, and water management. All sites were in the land clearing or foundation/framing stage of construction and were evaluated within 2 days after a rainfall event. Only four of the sites performed above the mean of the scoring scale, with the categorical scoring of BMPs indicating the worst performance for slope stabilization measures. The poor results suggest a failure to integrate scientific knowledge of erosion control with policy. A fundamental problem is the lack of basic site data on soil, topography, and hydrology, resulting in the incorrect application of BMPs, such as staging, filter fences, and berms. The current institutional framework for soil erosion control also provides disincentives to mitigate local erosion problems.     

Characteristics of worker accidents on NYSDOT construction projects

INTRODUCTION: This paper aims at providing cost-effective safety measures to protect construction workers in highway work zones, based on real data. Two types of accidents that occur in work zones were: (a) construction work area accidents, and (b) traffic accidents involving construction worker(s). METHODOLOGY/RESULTS: A detailed analysis of work zone accidents involving 36 fatalities and 3,055 severe injuries to construction workers on New York State Department of Transportation (NYSDOT) construction projects from 1990 to 2001 established that five accident types: (a) Struck/Pinned by Large Equipment, (b) Trip or Fall (elevated), (c) Contact w/Electrical or Gas Utility, (d) Struck-by Moving/Falling Load, and (e) Crane/Lift Device Failure accounted for nearly 96% of the fatal accidents, nearly 63% of the hospital-level injury accidents, and nearly 91% of the total costs. These construction work area accidents had a total cost of $133.8 million. Traffic accidents that involve contractors' employees were also examined. Statistical analyses of the traffic accidents established that five traffic accident types: (a) Work Space Intrusion, (b) Worker Struck-by Vehicle Inside Work Space, (c) Flagger Struck-by Vehicle, (d) Worker Struck-by Vehicle Entering/Exiting Work Space, and (e) Construction Equipment Struck-by Vehicle Inside Work Space accounted for nearly 86% of the fatal, nearly 70% of the hospital-level injury and minor injury traffic accidents, and $45.4 million (79.4%) of the total traffic accident costs. CONCLUSIONS: The results of this paper provide real statistics on construction worker related accidents reported on construction work zones. Potential preventions based on real statistics have also been suggested. IMPACT ON INDUSTRY: The ranking of accident types, both within the work area as well as in traffic, will guide the heavy highway contractor and owner agencies in identifying the most cost effective safety preventions.     

The hidden costs of relocating sand and gravel mines

Mining of construction aggregate is often unwelcome near communities because of its disamenities or because it can destroy prime farmland and displace other desirable land uses. Such conflicts have led to prohibitions against mining near cities or on high-value farmland, causing these operations to be relocated to more distant locations. The cost of this relocation may go unnoticed if they are indirect, diffused and rise gradually over time, but they may be significant due to the high transportation cost of moving these materials long distances.     

铁路事故救援系统的构建研究

在研究事故救援现状的基础上 ,分析并提出了铁路事故救援系统的构建条件 ,将铁路事故救援的可用资源分为内部资源和社会资源两大类 ,归纳总结了参与铁路事故救援的各部门组织的结构关系 ;根据实践中铁路事故救援的工作程序 ,归纳出事故救援系统的工作流程 ,探索了事故救援预案的构成内容 ;将铁路事故救援系统划分为救援资源、救援预案库、事故救援辅助决策等 6个功能模块 ,并进行了功能模块的分析以及系统的特点分析。该系统已经应用在大同铁路分局的运输生产中 ,达到了缩短救援响应时间、减少事故的损失和降低对运输生产的影响等效果。     

Genotoxicity of substances extracted from construction materials

Construction waste such as road pavement and concrete is estimated to constitute about 50% of the total industrial waste in Japan, and the recycling of such material has recently become a prominent topic among construction engineers. It has also been suggested that various types of industrial waste be utilized as components of construction materials. This paper investigates the environmental safety of certain materials in terms of the elutions and genotoxicities of these substances. The substances extracted from some materials, such as emulsifier, ash, and sediment, were found to have genotoxic characteristics. The dose-related responses of the various materials and their genotoxic strengths are shown. Received: June 16, 1998 / Accepted: September 7, 1999     

The relative contribution of wood and poly(vinyl chloride) to emissions of PCDD and PCDF from house fires

Emissions of PCDD/F from poly(vinyl chloride) (PVC) burned in house fires has been estimated at <1 g I-TEQ/yr in the US. In the current literature-based study, amounts of wood (21,000 kg) and PVC (180 kg) in a new house of standard construction are calculated and previously published emission factors for wood (0.01–173 μg/t) and PVC (3–6554 μg/t) are reported. Test conditions under which emission factors are generated differ and may not be directly comparable. Typically, PVC is tested at small-scale under relatively poor combustion conditions and wood is tested at large-scale under good combustion conditions. Thus, overall emission from combustion of these two materials of construction in house fires on an as-used basis is estimated to be similar (on the order of 1 g/yr) and a small contributor to the PCDD/F sources inventory. No speculation is made with respect to contents, roofing or other materials of construction.