Topic Review
Urban Flood Runoff Modeling in Japan
Since the 20th century, Japan has experienced a period of very rapid urbanization. Cities have experienced substantial densification and expansion, resulting in gradually elevated flood risk. Urban flooding has also occurred in most large cities in Japan, particularly in Tokyo. In response to this growing problem, much effort and resources have been spent on research and development aimed at understanding, simulating, and managing urban flood risk in Japan.
  • 165
  • 01 Aug 2023
Topic Review
Underlying Factors and Strategies for Organizational BIM Capabilities
Building information modeling (BIM) has a significant role in the architecture, engineering, construction, and operation (AECO) industries. Most BIM benefits have not been grasped due to the lack of organizational BIM capabilities (OBIMCs). Accordingly, organizations must develop intuitive strategies to support BIM implementation and to fulfill the promised benefits.
  • 642
  • 14 Nov 2022
Topic Review
Underground Spaces
Underground spaces with varying thermal, ventilation, and lighting environments can face problems of comfort, health, and safety. High temperatures, high humidity, difficulty in flue gas emission, harmful microorganisms, radon, and physical and psychological problems are examples of issues.
  • 1.5K
  • 11 Jan 2022
Topic Review
Uncrewed Aerial Vehicles in Bridge Inspection
Uncrewed Aerial Vehicles (UAV) constitute a rapidly evolving technology field that is becoming more accessible and capable of supplementing, expanding, and even replacing some traditionally manual bridge inspections. Given the classification of the bridge inspection types as initial, routine, in-depth, damage, special, and fracture critical members, specific UAV mission requirements can be developed, and their suitability for UAV application examined.
  • 485
  • 06 Apr 2022
Topic Review
Ultra-High-Performance Fibre-Reinforced Concrete
Ultra-high-performance fibre-reinforced concrete (UHPFRC) is a cementitious composite which contains fibres. UHPFRC has emerged as an effective structural retrofitting material due to its superior mechanical properties. In addition, UHPFRC has outstanding durability, ductility and workability; a low permeability; and a high abrasion and fire resistance. 
  • 239
  • 18 Apr 2023
Topic Review
Ultra-High-Performance Concrete (UHPC) Piles and Splicing Options
Conventional driven piles are made from steel, concrete, timber, or composite materials. These piling options have limitations with respect to corrosion, durability, driveablity, and performance. Ultra-High-Performance Concrete (UHPC) pile is a new alternative that has already been adopted by various state Departments of Transportation in the United States for addressing the limitations that exist with conventional piles. UHPC piles are made of a cementitious composite material mixture that possesses exceptional properties such as higher strength, low capillary porosity, and high resistance to corrosion, making them a suitable option for use as a deep foundation. For several reasons, it is necessary to cast piles with a shorter length and splice them at the site to reach the desired lengths.
  • 79
  • 07 Mar 2024
Topic Review
Ultra-High Performance Concrete Mixtures and Supplementary Cementitious Materials
Ultra-high performance concrete (UHPC) is a novel cement-based material with exceptional mechanical and durability properties. Silica fume, the primary supplementary cementitious material (SCM) in UHPC, is expensive in North America, so it is often substituted with inexpensive class F fly ash. However, future availability of fly ash is uncertain as the energy industry moves toward renewable energy, which creates an urgent need to find cost-effective and environmentally friendly alternatives to fly ash. Replacing cement, fly ash, and silica fume in UHPC mixtures with ground granulated blast-furnace slag (GGBFS), metakaolin, and a natural pozzolan (pumicite) are investigated. To identify acceptable UHPC mixtures (28-day compressive strength greater than 120 MPa), workability, compression, and flexural tests were conducted on all mixtures. Then, durability properties including shrinkage, frost resistance, and chloride ion permeability (rapid chloride permeability and surface resistivity tests) were evaluated for the acceptable UHPC mixtures. Results showed that 75, 100, and 40% of fly ash in the control mixture could be replaced with pumicite, metakaolin, and GGBFS, respectively, while still producing acceptable strengths. Flexural strengths were greater than 14.20 MPa for all mixtures. For durability, UHPC mixtures had shrinkage strains no greater than 406 μstrain, durability factors of at least 105, and “very low” susceptibility to chloride ion penetration, indicating that these SCMs are suitable candidates to completely replace fly ash and partially replace silica fume in non-proprietary UHPC.
  • 251
  • 16 Nov 2023
Topic Review
Types of Steel Liners
There are significant levels of concern about both the safety assessment and financial evaluation of the whole hydropower system, especially at early project stages. In addition, there is a variety of reliable and accurate methods for analysis, design, and optimization of steel pressure liners in hydropower plants. Several countries have developed specific regulations and codes for the design, installation, and safety evaluation of under-pressure piping, as well as estimates of the potential risks associated with failure. This article reviews the current methodologies and codes available for design and safety assessment of either unstiffened or stiffened pressure steel liners in hydropower plants.
  • 2.0K
  • 28 Mar 2022
Topic Review
Types of Insulation Materials
Insulation materials are classified into three main categories depending on material composition, material technology, and material sustainability index.
  • 2.1K
  • 11 Jan 2023
Topic Review
Trends and Challenges in Railway Sustainability
Rail is expected to become the backbone of future mobility in the world as the cleanest and greenest high-volume transport. Rail generates the lowest CO2 emissions and energy consumption when in operation, with respect to the other transportation modes, but during construction and maintenance phases, its environmental impacts are significant and need to be carefully assessed and properly mitigated.
  • 201
  • 18 Dec 2023
  • Page
  • of
  • 45