scholarly journals Asphalt Concrete Overlay Optimization Based on Pavement Performance Models

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Jan Mikolaj ◽  
Lubos Remek ◽  
Marian Macula
Keyword(s):  
Life Cycle ◽  
Asphalt Concrete ◽  
Life Cycle Cost ◽  
Cycle Length ◽  
Cost Benefit Analysis ◽  
Design Method ◽  
Cost Benefit ◽  
Climatic Conditions ◽  
Road User ◽  
Pavement Performance

The life cycle length of pavement with asphalt concrete material (ACM) surfacing is significantly influenced, in addition to transport loading and climatic conditions, by design method and rehabilitation timing. Appropriate overlay thickness calculation and estimation of optimal rehabilitation time are crucial to maximizing life cycle length and, concurrently, reducing road administration costs and road user costs. This article describes a comprehensive method of ACM rehabilitation design. For optimization of life cycle cost analysis (LCCA) based design, mathematical analytical solution in combination with experimental verification of physical, mechanical, and fatigue characteristics is utilized. Pavement performance, that is, functions mathematically describing pavement’s degradation characteristics of operational capability, is represented by longitudinal and transverse unevenness; these are used to describe relations between traffic loading and pavement’s bearing capacity on 1 : 1 scale. Optimizing of rehabilitation plan is carried out by making a cost benefit analysis (CBA) for several rehabilitation scenarios in which different rehabilitation timing produces different capital cost requirements and social benefits. Rehabilitation scenarios differ in technology, the design of which needs to be mathematically optimized, and timing of rehabilitation execution. This article includes a case study for the sake of illustration of practical results and verification of applicability of used methodology.

scholarly journals Design Method and Cost-Benefit Analysis of Hybrid Fiber Used in Asphalt Concrete

2016 ◽  
Vol 2016 ◽  
pp. 1-9
Author(s):  
Haiwei Zhang ◽  
Peiwen Hao ◽  
Yuan Pang ◽  
Aaron D. Mwanza
Keyword(s):  
Asphalt Concrete ◽  
Cost Benefit Analysis ◽  
Design Method ◽  
Polypropylene Fiber ◽  
Cost Benefit ◽  
Pavement Performance ◽  
Benefit Analysis ◽  
Hybrid Fiber ◽  
Pavement Engineering ◽  
The Cost

Fiber, as an additive, can improve the performance of asphalt concrete and be widely studied, but only a few works have been done for hybrid fiber. This paper presents a new and convenient method to design hybrid fiber and verifies hybrid fiber’s superiority in asphalt pavement engineering. Firstly, this paper expounds the design method used as its applied example with the hybrid fiber composed of lignin, polyester, and polypropylene fibers. In this method, a direct shear device (DSD) is used to measure the shear damage energy density (SDED) of hybrid fiber modified asphalts, and range and variance statistical analysis are applied to determine the composition proportion of hybrid fiber. Then, the engineering property of hybrid fiber reinforced asphalt concrete (AC-13) is investigated. Finally, a cost-benefit model is developed to analyze the advantage of hybrid fiber compared to single fibers. The results show that the design method employed in this paper can offer a beneficial reference. A combination of 1.8% of lignin fiber and 2.4% of polyester fiber plus 3.0% polypropylene fiber presented the best reinforcement of the hybrid fiber. The cost-benefit model verifies that the hybrid fiber can bring about comprehensive pavement performance and good economy.

Cost-Benefit Analysis and Optimization of Semiconductor Processing Water Recycling Strategy

2011 ◽  
Vol 71-78 ◽  
pp. 2772-2777 ◽  
Author(s):  
Qi Pan ◽  
Feng Wang ◽  
Hai Zhen Yang
Keyword(s):  
Life Cycle ◽  
Life Cycle Cost ◽  
Cost Benefit Analysis ◽  
Tap Water ◽  
Cost Benefit ◽  
Water Price ◽  
Water Recycling ◽  
Semiconductor Wafer ◽  
Optimal Processing ◽  
Processing Water

In this study, cost-benefit analyses based on life cycle assessment is applied to optimize the recycling of processing water for semiconductor factories. A representative 8-inch semiconductor wafer manufacturing plant is selected and seven existing or potential processing water-recycling sources were set, reverse osmosis (RO) reject, ultrafilter (UF) reject, multimedia filter (MMF), on-line analyzer drain, cation/anion (C/A) filter and merry-go-round (MGR) filter backwash water (including C/A sensor drain), wafer process organic drain and wafer process inorganic drain, marked as point 1 to 7, respectively. To sort the water-recycling sources in ascending order of the results of life cycle cost analyses, they were point 4, 5, point 2, 3, point 1, 7 and point 6, with life cycle the cost about 100,000$, 350,000$, 1000,000$ and 2000,000$, respectively. The order changed when they were sorted by their unit recycling-water costs; that was point 1, 2, point 5, point 3, 4 and point 7, with the unit recycling-water costs 0.2$/ton, 0.3$/ton, 0.4$/ton and 0.5$/ton, respectively. The analyses also evaluated the water recycling practice for various assumed unit tap water price. The optimal processing water recycling strategies based were proposed and corresponding optimal water-recycling rates were 24%, 64%, 81%, and 85% for water price 0.373$/ton, 0.578$/ton, 0.75$/ton and 0.945$/ton, respectively.

Sign in / Sign up

Export Citation Format

Share Document