Structural Engineering and Mechanics is the field of Civil Engineering particularly concerned with the analysis and design of a variety of structures such as buildings, bridges, dams, tunnels, highways, and airports.
Research projects focus on the application of Engineering Mechanics to the design of structures and facilities related to the urban infrastructure and construction in UAE. Research and study cover advanced structural analysis, design of steel and concrete structures, material testing and development of innovative materials in structures and construction, structural health monitoring, and high performance computational modeling and simulations in fluid and solid mechanics.
This project aims to non-destructive evaluation of health status of various materials, in particular, concrete, fiber-reinforce concrete (FRC), steel, CFRP/GFRP composites and bone, using a highly nonlinear solitary wave. The idea of assessing the health status is using a granular crystal sensor consisting of a linear chain of granular crystals able to support propagation of highly nonlinear solitary waves whose interaction with an adjacent inspection media is highly sensitive to the media’s mechanical properties. This research combines experimental and computational tools and aims at detecting defects (e.g., voids, cracks, corrosion, delamination, etc.) in structures through understanding of the fundamental physics of the interaction with highly nonlinear solitary waves and the inspected media. The sensitivity of wave localization, scattering and disintegration phenomena to the media’s mechanical properties will be explored via numerical modeling and validated against the experimental evidence.
In response to the UAE Surface Transport Master Plan 2030 objective to create an integrated road safety system, the Abu Dhabi City Municipality and Department of Transport are constantly looking for technologies to reduce high level of traffic accident fatalities. One important factor that influences road driving safety is skid resistance of an asphalt pavement. Recent studies have indicated that high ambient and pavement surface temperatures can influence significantly the reliability of skid resistance measurements. Motivated by this, this project aims to develop reliable experimental and computational techniques to account for the influence of asphalt pavement temperature on skid resistance measurements in UAE. This will be achieved on the basis of laboratory tests, field tests, and advanced computational techniques. The particular advantage of this approach is that for any given pavement surface the influence of environmental and operating conditions on skid resistance can be evaluated and quantified.
In response to the UAE Surface Transport Master Plan 2030 objective to create conditions for sustainable road infrastructure development, the Abu Dhabi Department of Municipal Affairs and Transport and the local asphalt industry are constantly looking for technologies to reduce consumption of raw materials, reduce emissions and increase recycling while still meeting the demand for construction efficiency and improved road performance. One such technology, currently under evaluation, is Warm Asphalt Mixes (WAM). The technology relies on the addition of various modifiers into the bitumen, one of the main components of asphalt pavements, which reduce its viscosity and enable a reduction of 20-55 C° of the temperatures at which typical asphalt is produced and placed with associated reductions in fuel consumption, lower greenhouse gas emissions and reduced odors and fumes. Another technology, consistent with sustainable development, is the utilization of Crumb Rubber (CR) originating from the recycling of scrap tires, as an additive in the bitumen for the production of what is known as Crumb Rubber Modified Bitumen (CRMB). It is estimated that it is possible to utilize more than 650 tires per lane kilometer. In the Warm Rubber Asphalt Concrete (Warman) project, the CRMB and the WAM technologies will be combined for the production of asphalt concrete mixes which combine all the mechanical and environmental advantages of the individual CR and WAM technologies.
It is expected that WarmRAC pavements will result to significant reductions to the current UAE scrap tyres stock piles, lower asphalt plant energy consumption, lower greenhouse gas emissions, reduced odors from mixing operations and reduced worker’s exposure to asphalt fumes. At the same time, it will enhance the performance of asphalt by increasing its resistance to high temperature permanent deformation, the main cause of damage in UAE, by at least 50% which will result to significant reduction of budgets for road repair, reductions in road closures for repair and hence reduction in traffic congestion. Another value-added use of waste tires in asphalt is their significant contribution to pavement noise reduction. Reductions in traffic noise, ranging from 40 – 90% are expected.
PI: Tom Skarpas
Co-PI: Michele Lanotte
Industry Partners: Municipality of Abu Dhabi
Khalifa University of Science and Technology – CIRA
Pavements require significant costs for maintenance, which is an overburden for many cities. To reduce these costs, a continuous and sustainable monitoring is required to detect damages at smaller scales. However, the pavements show complex damages such as surface deflection, localized strain, and cracks. Moreover, the pavements consist of layered structures for which performances with the traffic loads are different. To address these issues, detailed and continuous monitoring is essential to minimize the maintenance cost. Optical fiber sensors are utilized for pavements monitoring because it can measure continuous strains with high resolutions. The sensors will be installed beneath the pavement surface during field experiment. There is a significant potential that optical fiber sensors reduce maintenance costs of asphalt pavement because it is sustainable and identifies the damage with high resolutions.
(a) Image of Highway Pavements
(b) Installment of Optical Fiber Sensors for Field Experiment
PI: Tadahiro Kishida
Industry Partners: Fugro Middle East
Khalifa University Faculty Start Up Award
This research aims at corrosion detection and characterization in reinforced concrete (RC) structures via a novel non-destructive evaluation technique. Corrosion initiation and cracking will be detected via direct measurement of the mechanical properties of RC using highly nonlinear solitary waves (HNSWs). A novel granular crystal sensor will be developed to measure non-destructively site-specific mechanical properties (e.g., the modulus of elasticity) of RC and eventually provide a new and accurate corrosion detection marker based on direct measurement of RC strength. The proposed research is composed of an integrated suit of experimental and computational tools to understand interaction of HNSWs in a granular crystal sensor with adjacent RC. A computational technique consisting of a finite-element model in conjunction with a discrete-element model will be developed to understand fundamental physics of the solitary wave interaction with RC under corrosion. In-laboratory tests and numerical study will be also performed for RC damage detection due to steel corrosion.
Dr. Tae Yeon Kim
Many studies have been recently carried out in the attempt to combine traditional pavement materials with polymeric waste to obtain a better performing product from the mechanical as well as the environmental perspective.
Plastic waste represents a massive source of polymeric material. Every second about 20,000 plastic bottles are being bought around the world which corresponds to about 480 billion plastic bottles. It is expected that by 2021 the production will increase to 583 billion. Most plastic bottles are made from PolyEthylene Terephthalate (PET) which is highly recyclable. Nevertheless, data from 2016 shows that less than half of the bottles bought in one year were collected for recycling and just 7% of those collected were turned into new bottles. Instead most ended up in a landfill or in the ocean. Even though recycling technologies are currently available for reprocessing plastic, it is still extremely difficult to deal with the impressive quantity of plastic accumulated over the years. In the UAE, it has been evaluated that around 5 billion tons of general plastic waste will be reversed in the environment by 2030. This is the equivalent plastic amount generated by over 380 trillion plastic bottles.
The PEAM project aims to investigate the chemo-physical interactions between different types of plastic waste and the asphalt bitumen in the view of developing a reliable methodology to combine these two materials and enhance the mechanical properties of the final mix.
Personnel: Industry Partners: Municipality of Abu Dhabi
PI: Michele Lanotte
Funding: Khalifa University of Science and Technology – Faculty Start-up Award