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Sustainability Life Cycle Cost Analysis of Roof Waterproofing Methods Considering LCCO2  [PDF]
Sangyong Kim,Gwang-Hee Kim,Young-Do Lee
Sustainability , 2014, DOI: 10.3390/su6010158
Abstract: In a construction project, selection of an appropriate method in the planning/design stage is very important for ensuring effective project implementation and success. Many companies have adopted the life cycle cost (LCC) method, one of the methods for analyzing economic efficiency, for appropriate decision-making in the basic/detailed design stage by estimating overall costs and expenses generated over the entire project. This paper presents an LCC method for calculating the LCC of CO 2 (LCCO 2), based on materials committed during the lifecycle of a structure for each roof waterproofing method and adding this cost to the LCC for comparative analysis. Thus, this technique presents the LCC that includes the cost of CO 2 emission. The results show that in terms of initial construction cost, asphalt waterproofing had the highest CO 2 emission cost, followed by sheet waterproofing. LCCO 2 did not greatly influence the initial construction cost and maintenance cost, as it is relatively smaller than the LCC. However, when the number of durable years was changed, the LCC showed some changes.
Building waterproofing remediation applying the 'total cut' method  [PDF]
Gavrilovi? Dragan J.
Facta Universitatis Series : Architecture and Civil Engineering , 2011, DOI: 10.2298/fuace1101105g
Abstract: The paper analyzes the specific problems of construction of a waterproofing system with an absolute control of the vertical penetration of ground water and dampness from the ground into higher levels of building masonry structure. This method can very suitably be applied in rehabilitation of old brick buildings where the usual waterproofing remediation systems cannot be implemented because of specific structure system The 'total cut' method is very suitable for use in the old traditional masonry buildings, which do not have reinforced concrete vertical beams and where using this method would not interfere with the continuous stability of the building.
Characterization and Valorization of Two Algerian Bentonites in the Waterproofing Systems  [PDF]
Messaouda Debieche, Farid Kaoua
Materials Sciences and Applications (MSA) , 2014, DOI: 10.4236/msa.2014.55040
Abstract:

The interest in environment has recently considerably grown, and its protection is now included in the continuous action of the governments and the industries. In Algeria, the different types of waste are currently produced in almost 3.000 illegal dumps, occupying approximately 150.000 hectares. To overcome this problem, waterproofing sites prove the most appropriate solution. It is a geotechnical method to guard against the action of water by narrowing the flow of water through a surface in a given time. The site’s waterproofing technique, in the landfills sites, is nowadays a very necessary condition to protect the environment, which requires the use of appropriate materials. This work deals within the valorization of local materials (sand and bentonite), in the waterproofing technique of the technical landfills site “TLS”. To this end, two types of bentonites from the west of Algeria are used. In order to achieve an optimal mixture, ensuring good performance in terms of hydraulic conductivity, durability and shear strength, mixtures based of sand at different concentrations of bentonite, at compact state are prepared and studied. This study showed that a low permeability of mixture (sand/bentonite) can be achieved with introducing 8% of a calcium bentonite, against 6% of a sodium bentonite. The latter presents a great adsorption capacity and a self healing ability, compared to calcium bentonite. This gives a good sustainability against climate variations of mixture based on sodium bentonite. This mixture has also confered a good mechanical behavior, expressed by the recorded, reduction of the friction angle (Φ) and the increase of the cohesion (C). Therefore it represents an optimal mixture for waterproofing systems, due to its economical and ecological advantages.

一次性餐盒材料中全氟辛酸和全氟辛烷磺酸沥出性研究  [PDF]
潘媛媛,史亚利,王亚(韦华),蔡亚岐
环境化学 , 2015,
Abstract: 利用高效液相色谱-串联质谱检测方法对一次性餐盒材料中可沥出性全氟辛酸(PFOA)和全氟辛烷磺酸(PFOS)进行了研究.分别选取水、3%乙酸(W/W)、15%乙醇(V/V)和正己烷4种浸取液模拟餐盒材料在使用过程中可能接触到的水性、酸性、酒精类和油脂类条件.材料经4种溶液浸提后,浸取液用固相萃取净化和浓缩,目标分析物PFOA和PFOS采用内标法进行定量.研究表明,一次性餐盒材料在模拟条件下中有以PFOA为主的全氟类化合物从材料中沥出,其中酸性环境对PFOA的浸取率最高(2296ng·m-2),为其它3种方法的82.8倍;4种浸提条件下PFOS的沥出率都比较低,浓度仅为0.7ng·m-2—5.4ng·m-2.
Natural and artificial ageing for evaluating waterproofing treatments for marble
Laurenzi Tabasso, Marisa,Mecchi, Anna María
Materiales de Construccion , 1992,
Abstract: Exposure of samples to artificial ageing is commonly carried out to test the durability of natural and artificial stones and the effectiveness of products used for their conservation. Correlations between artificial and natural ageing, however, are not always well understood mainly because the former can only try to simulate, in a faster but simplified way, the effects of the many causes interacting ín natural environments. In the present study, marble samples from Carrara and Proconnesion quarries, were treated with four waterproofing products (or mixtures of products) and exposed to artificial ageing while an analogous set was exposed outdoor, in the town center of Rome for two years. Several physical parameters were measured before and after the ageing and the experimental results enabled us to compare the effects produced by the different types of ageing and to estimate the correlations between them. As for the durability of the tested waterproofing products, the two systems are in good agreement even if two years of natural ageing resulted to be slightly more severe than 33 days of exposure to saline fog, to UV radiation and to wetting-drying cycles. La exposición de muestras a envejecimiento artificial se lleva a cabo comúnmente para chequear la duración de las piedras naturales y artificiales y la eficacia de los productos usados para su cuidado. Las correlaciones entre el envejecimiento artificial y natural, sin embargo, no siempre se entienden bien principalmente porque el envejecimiento trata de simular, de una manera rápida pero sencilla, los efectos de las muchas causas que actúan en el ambiente natural. En este estudio, muestras de mármol de las canteras de Carrara y Proconnesio, han sido tratadas con cuatro productos o mezclas de productos, para su impermeabilización y expuestos a envejecimiento artificial. Mientras, un juego análogo de piedras se exponía al exterior en el centro de la ciudad de Roma, por un período de dos a os. Se midieron diferentes parámetros físicos antes y después del envejecimiento y los resultados de la experiencia han permitido comparar los efectos producidos por los diferentes tipos de envejecimiento y de establecer las correlaciones entre ellos. Para la evaluación de los productos de impermeabilización, los dos sistemas son muy parecidos, aunque dos a os de envejecimiento natural han resultado ser algo más duros que 33 días de exposición a niebla salina, radiaciones UV y ciclos de humedad-sequedad.
污泥生物沥浸处理技术及其工程应用  [PDF]
周立祥
南京农业大学学报 , 2012, DOI: 10.7685/j.issn.1000-2030.2012.05.017
Abstract: 污泥高水分含量和存在重金属已成为影响我国污泥处置与资源化的重要"瓶颈"。生物沥浸技术被证实是一种即可以有效去除污泥重金属,同时显著提高污泥脱水性能的生物方法。本文较系统介绍了目前我国污泥深度脱水的几种方法及生物沥浸处理技术在污泥处理上的优势,生物沥浸法促进污泥深度脱水和重金属去除的基本原理、工艺流程及影响因素。以无锡芦村污水处理厂日处理200t污泥的生物沥浸处理――高温发酵堆肥的实际工程为例,阐述该工艺的技术参数、污泥处理及其后续堆肥和土地利用的效果。连续2年多的生产性试验和工程实践表明,经生物沥浸处理的污泥可不加任何絮凝剂能一步机械脱水到含水率60%以下,呈土黄色无臭的半干化饼状。且污泥干基有机质、热值和氮磷养分含量几乎不变,利于后续资源化(如土地利用、焚烧等),处理成本低廉,同时压滤水水质较好,可就近排入污水处理厂处理。因此,污泥生物沥浸技术是一项有广泛应用前景和市场需求的新技术。
Experimental Study on the Roll of Waterproofing Admixtures on the Strength and Durability of Concrete
A. Geetha,P. Perumal
Journal of Engineering and Applied Sciences , 2012,
Abstract: This study deals, the durability and strength of concrete using admixtures. This addition of water proofing admixtures turns concrete into a construction material in harmony with sustainable building development. The addition of water proofing admixtures also increases the various strength of concrete. These studies were carried out by conducting tensile, compressive and flexural strength tests of the concrete specimen with and without admixtures for various dosages and various curing periods of 7 and 28 days. For flexural strength concrete prism of size 100x100x500 mm, for compression test cube of 150x150x150 mm, for split tensile test cylinders of 150x300 mm. For durability study permeability tests were conducted on the cube specimen of size 150x150x150 mm. The results showed that the presence of waterproofing admixtures always improves the corrosion resistance and thus, increases the strength of concrete.
臭氧氧化法深度处理生活垃圾焚烧厂沥滤液  [PDF]
穆永杰,叶杰旭,孙德智
环境工程学报 , 2013,
Abstract: 采用臭氧氧化法对生活垃圾焚烧厂沥滤液经生化处理后的废水(称沥滤液生化处理水)进行深度处理。实验结果表明,COD降解速率随废水pH的提高明显增加,其中pH=10.5时的COD降解速率常数约为pH=4时的5.8倍。在臭氧投量为52.92mg/min、pH=10.5的条件下反应70min后,UV254和COD去除率分别达到84.7%和59.3%。向反应体系投加叔丁醇后COD去除率下降了约15%,由羟自由基氧化去除的COD占总COD去除量的26.7%。毒性实验结果表明,沥滤液生化处理水的96h-EC50为38%,经臭氧氧化进一步处理后出水的96h-EC50为77%,表明经臭氧深度处理后沥滤液生化处理水的毒性明显降低。
臭氧深度处理垃圾焚烧厂沥滤液时溶解性有机质(DOM)特性分析  [PDF]
穆永杰,叶杰旭,孙德智
环境化学 , 2015,
Abstract: 采用荧光光谱、红外光谱和紫外-可见光谱技术分析了臭氧氧化深度处理沥滤液生化处理水过程中废水中DOM组成及结构变化.同步荧光光谱显示,反应过程中340-370nm处的特征峰强度明显下降,小于270nm的短波长范围内荧光强度有一个从高到低再升高的变化过程.三维荧光光谱表明,沥滤液生化处理水中含有两个类富里酸荧光峰(UV-FAEx/Em=250-255/410-450nm;Vis-FAEx/Em=315-320/400-405nm),反应过程中荧光峰强度不断降低,其中UV-FA荧光峰的发射波长存在明显的蓝移现象,最大蓝移量40nm.红外光谱表明,沥滤液生化处理水中含有多种芳香性特征峰,臭氧氧化过程中峰强度逐渐降低,部分特征峰消失,并有过氧化合物的CO伸缩振动峰生成.沥滤液生化处理水经臭氧氧化深度处理60min后,其SUVA254值由3.01L·mg-1·m-1降低到1.16L·mg-1·m-1,A3/A4值由4.06上升到8.43.综合分析表明,臭氧氧化能够有效将沥滤液生化处理水中结构复杂的大分子芳香族化合物降解为芳构化程度较低、分子量较小的有机物.
城市污泥中Cu回收研究:生物沥浸-溶剂萃取-电积沉Cu技术  [PDF]
陈海平,周立祥,王世梅,梁剑茹
环境科学 , 2009,
Abstract: 城市污泥通常含有大量有机质但也存在数量不等有害金属,在不影响污泥有益成分的基础上,去除和回收污泥中金属,既使污泥无害化又产生经济效益,意义重大.针对苏州某工业园区污泥重金属含量较高,研究利用生物沥浸-溶剂萃取-电积技术回收城市污泥中重金属Cu的工艺,并探讨了采用5-壬基水杨醛肟萃取剂M5640从城市污泥生物沥浸液中萃取分离Cu和Fe的最佳工艺参数.结果表明,经过生物沥浸处理72 h后,城市污泥中重金属Cu溶出率高达90%.当最佳工艺条件为:萃取剂体积分数为2%,相比(有机相与水相体积比,以O/A表示)为1/3,沥浸液pH为2.0时,沥浸液中Cu的一级萃取率达到95%以上,而Fe的共萃率低于10%;反萃取试验结果表明,在反萃取相比为2/1的条件下用1.5mol/L硫酸溶液进行反萃取,Cu的一级反萃取率达到80.07%;反萃取后的富集Cu溶液作为电解液,在槽电压为2.1 V、电解温度为55℃条件下电积6 h,Cu回收率达到90%以上.在整个工艺中萃余液和反萃液均可循环利用无废液排放,对含Cu高的污泥,利用生物沥浸-溶剂萃取-电积技术回收有良好的应用前景.
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