Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Civil and Environmental Engineering Reports

Powiadomienia systemowe

Sesja wygasła!
Sesja wygasła!
Sesja wygasła!

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Performance of Solid Waste Landfills Under Earthquake-Induced Vibrations

Seyedi Marghaki Behnaz, Soltani Fazlollah, Noroozinejad Farsangi Ehsan, Sivandi-Pour Abbas

Civil and Environmental Engineering Reports

2022

Vol. 32, no. 2

1--22

The stability inside the waste, internal stability, and co-stability between the elements of the insulation system and the landfill bed should be considered in the landfill design. The stresses and the resulting deformations in both mineral and geosynthetic materials of the insulation system must be controlled in the design, so that an unpredictable flow path is not created. Besides, long-term durability in the insulation system should be considered. An evaluation of the durability of the system requires knowledge of the interaction between the components and the waste as a settling object. The numerical modeling methods can be used to evaluate the local instability. In this study, a landfill constructed in the UK has been modeled in ABAQUS finite element platform and was verified with the results of obtained data from precision instruments at the landfill site. Then, by applying the earthquake excitations, the seismic behavior of the solid waste landfill under Far-Field and Near-Field earthquakes and their effect on the durability of the landfill wall system were investigated. The outputs include maximum displacement, maximum stress, the most critical state, and investigation of yield stress and rupture of the geomembrane layer. The results indicated that in the landfill wall, the maximum displacement occurs in the waste section. It occurs especially between the boundary of natural soil and waste. It was also observed that the geomembrane layer under the earthquake loadings had experienced some ruptures.

Performance Assessment of Steel Moment Connections Retrofitted With Various Reduced Section Patterns

Sivandi-Pour Abbas

Civil and Environmental Engineering Reports

2019

Vol. 29, no. 4

1--17

It is of high importance in seismic retrofitting of lateral load-bearing systems to increase the connections performance. The crucial point in the steel frame retrofitting process is to create plastic hinges in these types of frames. The formation of plastic hinges in beams and near columns generates large strains on column flanges as well as welding metal and heated surroundings, which can lead to brittle failure. The connection should be designed in such a way as to allow plastic hinge formation at certain points of the beam. One such method suggested for retrofit connections is to reduce the beam section locally away from the connection zone. There are various patterns available to locally reduce the beam section, such as circular, elliptical, and symmetric/asymmetric. In recent years, different proposals have been presented to design these connections which vary from older instructions. For this study, radiused cuts in the flange and slotted holes in the web of connection beams were selected for retrofitting analysis. Cyclic behavior, energy damping levels, and ductility of these connections were studied and compared before and after the retrofit by using nonlinear dynamic analysis. The results showed that the symmetrical circular hole pattern in the beam flanges demonstrated reliable performance.