Seepage Induced Landfill Capping Failures and a Conservative Method for Designing Landfill Lateral Drainage Layer

Author(s):  
Aigen Zhao
2021 ◽  
pp. 096777202199517
Author(s):  
Charles DePaolo

Dugald Blair Brown, a military surgeon and Fellow of the Royal College of Surgeons, Edinburgh, published twelve papers containing 77 case studies of gunshot wounds that he had treated in the Anglo-Zulu War of 1879 and in the First Anglo-Boer War of 1880–1881. Brown devised a “conservative” method of surgery, the early development of which had been influenced by Thomas Longmore (1816–1895), Joseph Lister (1827–1912), F. J. von Esmarch (1823–1912), and Carl von Reyher (1846–1890). During these conflicts, Brown reacted to surgical practices unsuited to the battlefield and not in the interest of the wounded. One such practice was “expectant” surgery, the practitioners of which dangerously substituted natural healing for immediate wound resection. Brown also criticized “operative” surgeons who, when faced with gunshot wounds of the extremities, expeditiously amputated limbs. Viewing each case as diagnostically unique, Brown tried to salvage limbs, to preserve function, and to accelerate recovery. To achieve these objectives, he used debridement, antisepsis, drainage, nutrition, and limited post-operative intervention.


2021 ◽  
Vol 13 (13) ◽  
pp. 7115
Author(s):  
Mostafa Kazemi ◽  
Luc Courard ◽  
Julien Hubert

A green roof is composed of a substrate and drainage layers which are fixed on insulation material and roof structure. The global heat resistance (Rc) within a green roof is affected by the humidity content of the substrate layer in which the coarse recycled materials can be used. Moreover, the utilization of recycled coarse aggregates such as incinerated municipal solid waste aggregate (IMSWA) for the drainage layer would be a promising solution, increasing the recycling of secondary resources and saving natural resources. Therefore, this paper aims to investigate the heat transfer across green roof systems with a drainage layer of IMSWA and a substrate layer including recycled tiles and bricks in wet and dry states according to ISO-conversion method. Based on the results, water easily flows through the IMSWAs with a size of 7 mm. Meanwhile, the Rc-value of the green roof system with the dry substrate (1.26 m2 K/W) was 1.7 times more than that of the green roof system with the unsaturated substrate (0.735 m2 K/W). This means that the presence of air-spaces in the dry substrate provided more heat resistance, positively contributing to heat transfer decrease, which is also dependent on the drainage effect of IMSWA. In addition, the Rc-value of the dry substrate layer was about twice that of IMSWA as the drainage layer. No significant difference was observed between the Rc-values of the unsaturated substrate layer and the IMSWA layer.


Author(s):  
Andrew E. Loken ◽  
Joshua S. Steelman ◽  
Scott K. Rosenbaugh ◽  
Ronald K. Faller

Autonomous vehicles (AV) differ significantly from traditional passenger vehicles in both their behavior and physical characteristics. As such, the validity of the guidance provided in the Manual for Assessing Safety Hardware, Second Edition (MASH 2016) is questionable in AV applications. Impact angles, speeds, and vehicle weights specified in MASH 2016 are inextricably linked to the traditional vehicles underlying the estimates. For AV applications, these parameters must be estimated from the ground up, stepping outside the guidance of MASH 2016. In this paper, a conservative method for evaluating existing infrastructure to support AV traffic is proposed. The method integrates traditional structural analyses with unconventional methods of estimating impact conditions. This methodology was developed for the Jacksonville Transportation Authority, who, when faced with unique challenges in maintaining and expanding their Automated Skyway Express, opted to convert the system from monorail to AV traffic. Leading AV developers were surveyed to develop a portfolio of potential candidates for the conversion. Estimated impact conditions were then compared against the capacity of the system’s existing concrete parapets. Ultimately, safe operating speeds for each AV candidate were recommended on the bases of structural capacity and vehicle stability. All but one AV candidate were deemed capable of safely operating at the desired speed of 25 mph without any modifications to the barrier. Although the methodology was developed for a particular case, it is applicable to future implementations of AVs on existing infrastructure, provided the roadway is confined similarly to the Skyway deck.


2017 ◽  
Vol 20 (3) ◽  
pp. 528-553 ◽  
Author(s):  
Han-Cheng Dan ◽  
Zhi Zhang ◽  
Xiang Liu ◽  
Jia-Qi Chen

2021 ◽  
Vol 25 (5) ◽  
pp. 39-45
Author(s):  
A.Kh. Sariev ◽  
N.Yu. Cherbakova ◽  
N.Yu. Terentyeva

The assessment of the possibility of creating a plant-soil cover on an artificially created seal-gravel drainage layer with a rocky bed (h=110¸150 cm), on the disturbed areas of the adjacent areas of tailings storage facilities. Research for 2017–2019 shows that when sowing recult-vants with sowing standards of 150–200 kg/ha and doses of fertilizer N60P60K60 and N120P60K60 on an artificial substrate it is possible to form meadow formations with a density of grass 10–12000 pc/m2 and average productivity of 21–24 c/ha. A plant-soil-blooded blood with a turf layer of 8–10 cm is created with the simultaneous overlap of heavy metals of man-made substrates and elimination of pulp sands dusting, which contributes to the improvement of the microclimate of the environment.


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