轻质高强多功能点阵夹层结构研究进展

根据材料类型和点阵结构,对点阵夹层结构进行了分类简述,并从静态、动态力学性能上,分析了各类点阵夹层结构的优缺点。简要叙述了设计过程中,综合考虑材料、结构以及功能等影响因素,针对不同使用工况的要求,可对各影响因素进行匹配设计,以实现传热特性、电磁波屏蔽特性、声学特性等不同的功能性需求。然后介绍了复合点阵夹层结构(嵌锁组装、模具热压成形、穿插编织)和金属点阵夹层结构(冲压成形、挤压线切割、拉伸网折叠、搭接拼装、熔模铸造以及增材制造)的主要制造工艺。最后提出如何将设计因子与多目标进行匹配及优化设计,是轻质高强点阵夹层结构的重点研究方向,轻质高强点阵夹层结构将朝多材料及多结构复合方向发展,开发新的制造工艺,提高费效比,是点阵夹层结构材料需解决的问题。     

减噪路面的降噪机理及其结构

阐述了减噪路面的降噪机理，并提供了几种减噪路面结构及实测数据，对高速公路设计有着重要的参考意义。     

废旧橡胶粉用于道路改性沥青的研究

从环保的角度出发，利用废旧橡胶粉对道路沥青改性进行了试验研究，分析了废胶粉的细度及掺量对沥青性能的影响，并就橡胶粉改性沥青所采用的胶粉细度、掺量以及改性措施提出了合理的建议。     

小型炭素焙烧炉沥青烟气净化技术初探

阐述了颗粒层吸附技术在小型炭素焙烧沥青烟气净化中的应用。     

基于地理信息系统的UPMIS安全设计

重点论述基于地理信息系统 (GIS)的城市路面管理信息系统 (UPMIS)安全设计的主要思路。即对城市道路具体路面的有关属性编码之后 ,通过GIS信息平台将路面空间属性与路面属性数据联系起来生成路面空间信息系统。从而使路面的管理与道路的地理信息相结合 ,使管理更加直接、形象。并且将研究应用到秦皇岛市路面管理系统的设计中 ,效果很好。笔者通过研究 ,为城市道路信息可视化管理作一些有益的探索。     

高地下水位地区透水停车场的水文控制效果

为确定高地下水位地区透水铺装对路面径流的水文控制效果,在上海市区建造了4个实验性透水铺装单元与1个不透水铺装对照,其中3个为设有防水衬底的不透型设施分别为透水混凝土铺装(设施Ⅰ)、水泥稳定碎石基层/缝隙透水砖面层(设施Ⅱ)、碎石基层/缝隙透水砖面层(设施Ⅲ),1个普通缝隙透水砖铺装(设施Ⅳ),以及1个不透水混凝土对照(设施0).历时1年监测了实际降雨条件下4种实验设施的表面径流、排水管出流流量及表面渗透速率,考察不同设施的径流总量削减率、峰值削减及峰现延迟能力.结果表明,缝隙透水砖面层的表面稳定渗透速率明显小于透水混凝土面层,使用1年后,2种面层表面稳定渗透速率均明显下降;4种设施的表面产流均无显著差异;3种不透型设施的就地消纳水量能力均较弱,年径流总量控制率分别为24.2%、28.5%、28.4%,排水管不发生出流的控制降雨量分别为5.2 mm、7.8 mm、7.8 mm;设施Ⅰ的峰值削减与峰现延迟效果弱于设施Ⅱ及设施Ⅲ,且3种设施的峰值削减率和峰现延迟时间与降雨强度呈现显著负相关性.     

袋式除尘器在沥青混凝土搅拌设备上的应用

分析了沥青混凝土搅拌设备的构成以及生产沥青混凝土的工艺及烟尘特点;通过应用工程实例,指出袋式除尘器是沥青混凝土搅拌设备最理想的除尘系统之一。     

Utilization of cement kiln dust (CKD) in cement mortar and concrete—an overview

Solid waste management is one of the major environmental concerns around the world. Cement kiln dust (KKD), also known as by-pass dust, is a by-product of cement manufacturing. The environmental concerns related to Portland cement production, emission and disposal of CKD is becoming progressively significant. CKD is fine-grained, particulate material chiefly composed of oxidized, anhydrous, micron-sized particles collected from electrostatic precipitators during the high temperature production of clinker. Cement kiln dust so generated is partly reused in cement plant and landfilled. The beneficial uses of CKD are in highway uses, soil stabilization, use in cement mortar/concrete, CLSM, etc.Studies have shown that CKD could be used in making paste/mortar/concrete. This paper presents an overview of some of the research published on the use of CKD in cement paste/mortar/concrete. Effect of CKD on the cement paste/mortar/concrete properties like compressive strength, tensile strength properties (splitting tensile strength, flexural strength and toughness), durability (Freeze–thaw), hydration, setting time, sorptivity, electrical conductivity are presented. Use of CKD in making controlled low-strength materials (CLSM), asphalt concrete, as soil stabilizer, and leachate analysis are also discussed in this paper.     

Chloride Released from Three Permeable Pavement Surfaces after Winter Salt Application

Few studies exist on how chloride from chloride‐based deicers is transported in infiltration‐based stormwater control measures. In 2009, the U.S. Environmental Protection Agency (USEPA) constructed a 0.4 ha parking lot in Edison, New Jersey, that was surfaced with permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). Each surface type has four equally sized, lined sections that direct all infiltrate to separate 5.7 m³ collection tanks. The USEPA acute criterion for aquatic life (860 mg/l) was exceeded in events immediately following a snow event. Concentrations of the infiltrate exceeded the detection limit (5 mg/l) year round but did not exceed the USEPA chronic toxicity (230 mg/l) after April. The chloride concentration decreased with cumulative rainfall since previous snow event, and a power regression described this relationship. In the power regression, the coefficient (b) described the initial concentration following a snow event, and the exponent (m) described the rate in which chloride was flushed through the system with infiltrating water. PC had the largest coefficient (5,664) and largest absolute exponent (?0.92), followed closely by PICP (b = 4,943 and m = ?0.87), and distantly by PA (b = 2,907 and m = ?0.67). The differences in release rate were proportional to the measured surface infiltration rates of 4,000; 2,400; and 200 cm/h for PC, PICP, and PA, respectively. These results will assist those who manage or regulate stormwater where receiving waters are chloride impaired.     

100% recycled hot mix asphalt: A review and analysis

A holistic evaluation of the feasibility of producing 100% recycled mixtures is presented. Eleven technologies readily available for producing 100% Reclaimed Asphalt Pavement (RAP) hot asphalt mixtures are described in the article and the complementary video (http://youtu.be/coj-e5mhHEQ). The recorded performance of 100% RAP mixtures is analyzed along with identification of typical high RAP distresses. Recommended mix design procedures and the best RAP management strategies are described. A cradle-to-gate analysis of environmental effects indicated 18 kg or 35% CO₂eq savings per t of produced 100% RAP asphalt mixture compared to virgin mix, while cost analysis showed at least 50% savings in material related expenses.