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Hydropower and Floods
Published in Saeid Eslamian, Faezeh Eslamian, Flood Handbook, 2022
Sachin Kumar, Aanchal Singh S. Vardhan, Akanksha Singh S. Vardhan, R. K. Saket, D.P. Kothari, Saeid Eslamian
When permanent defenses fail, temporary emergency measures such as sandbags, hydro sacks, flood stop flood barriers, or portable inflatable tubes are used, as shown in Figure 5.32. In 1988, a method of using water to control was discovered. This was accomplished by containing two parallel tubes within a third outer tube. When filled, this structure formed a non-rolling wall of water that can control 80% of its height in external water depth, with the dry ground behind it. Eight-feet-tall water-filled barriers were used to surround Fort Calhoun Nuclear Generating Station during the 2011 Missouri River flooding. Instead of trucking in sandbag material for a flood, stacking it, and then trucking it out to a hazmat disposal site, flood control can be accomplished using the onsite water. However, these do not become foolproof. A water-filled rubber flood berm eight feet (2.4 m) high and 2,000 feet (610 m) long that surrounded portions of the plant was punctured by a skid-steer loader, and it collapsed, flooding a part of the facility (Hydro, 2018).
Evaluation of Design Methods for Helical Piles
Published in Chong Tang, Kok-Kwang Phoon, Model Uncertainties in Foundation Design, 2021
The equipment used to install helical piles includes a truck-mounted auger or hydraulic torque motor attached to a backhoe, forklift, front-end loader, skid-steer loader, derrick truck or other hydraulic machine. An example of installation equipment is presented in Figure 7.7. The principal component is the hydraulic torque motor that is used to apply torsion to the pile shaft head. To allow the helical bearing plates to advance with minimal soil disturbance, helical piles should be installed with high-torque and low-speed motors. The torque motor should have clockwise and counterclockwise capability and should be adjustable with respect to revolutions per minute to ensure proper pile alignment and position. The connection between the torque motor and helical pile should be in-line, straight and rigid and should consist of a hexagonal, square or round adapter and helical shaft socket. This is typically accomplished using a manufactured drive tool. A high-strength, smooth, tapered pin is used to connect the pile shaft with the drive tool. A basic, convenient and useful aspect of most helical piles is that the capacity can be verified from the installation torque. The relation between capacity and installation torque has been established, as discussed in subsequent sections of this chapter. A torque indicator will be used to measure torque during installation. To ensure accuracy, the torque indicator should be calibrated prior to installation.
Case studies
Published in Sahadat Hossain, Sadik Khan, Golam Kibria, Sustainable Slope Stabilisation using Recycled Plastic Pins, 2017
Sahadat Hossain, Sadik Khan, Golam Kibria
Field installation in slide area S3 at the I-70 Emma site took place on 6-7 January 2003. Before the slope stabilisation, the sliding area was regraded to the original slope configuration. RPPs were installed using two different pieces of equipment: an Ingersoll Rand ECM350 track-mounted drill rig, with an extended boom and a simple drop- weight device, and the Farm King post driver, commonly used for driving fence or guard-rail posts, mounted on a skid-steer loader. Both types of equipment performed exceptionally well, with a rapid production rate. A total of 199 reinforcing members were installed in slide area S3. RPPs were generally driven without any significant problems, and the overall installation was completed in less than two working days.
Structural equation modelling of lower back pain due to whole-body vibration exposure in the construction industry
Published in International Journal of Occupational Safety and Ergonomics, 2019
Vitharanage Hashini Paramitha Vitharana, Thanwadee Chinda
Palmer et al. [14] showed that the construction industry is the largest industry contributing to WBV exposure. Construction workers are usually exposed to WBV through the use of heavy equipment. The exposure level of WBV is very high among those heavy equipment operators, including soil roller, excavator, motor grader, skid-steer loader and dozer operators [15]. Waters et al. [16] mentioned that heavy equipment operators are at higher risk of developing LBP in comparison with those who are not working with heavy equipment. Boshuizen et al. [17] stated that 68% of workers in the construction industry suffer from LBP regularly, and the prevalence of LBP is 25% higher among the workers who are exposed to WBV. Ueno et al. [18] mentioned that LBP is the primary cause of occupational sick leave for 4 days or more in the construction industry in Japan. Guo et al. [19] agreed that LBP is a major cause of morbidity and lost production for US construction workers.
Recycled concrete aggregate/municipal glass blends as a low-carbon resource material for footpaths
Published in Road Materials and Pavement Design, 2018
Arul Arulrajah, Monzur Imteaz, Suksun Horpibulsuk, Yan-Jun Du, Jack Shui-Long Shen
The base material blend of 85RCA/15FRG was mixed to the appropriate OMC in a pug-mill at the C&D recycling facility and transported by truck to the site, a haulage time of approximately 15 min. The material was planned to be placed and compacted at field moisture content close to the OMC, with the use of plant mixed wet mixes, to achieve a uniform density within the base. After placement and rough spreading using a skid-steer loader, the 85RCA/15FRG base layer was compacted with a vibratory plate compactor until there was no further surface deformation when walking on it. The surface was left with an open texture and the final prepared surface was uniform. Overall the 85RCA/15FRG blend was easily placed and yielded an adequately tight surface. Field samples were collected in sample bags from three locations in each section of the footpath base and combined into a single sample (>7 kg) for laboratory testing for the determination of compaction and particle size distribution properties. For the assessment of the construction variability of 85RCA/15FRG and their impact on base strength and stiffness, field testing was conducted at various locations along the pavement using a Nuclear Density Gauge and Clegg Hammer after the placement of the base layer. The tests were conducted within 2 h of placement of the base layer.