STUDY OF DYNAMIC BEHAVIOR OF EARTH DAMS CONSIDERING THE DAM BASE

The methods have been developed for solving various dynamic problems for inhomogeneous viscoelastic structure-base systems taking into account wave entrainment of energy, i.e. non-reflecting conditions at the boundary of the finite site of the base. The dynamic behavior and the stress-strain state of the inhomogeneous “viscoelastic dam-elastic base” system using wave entrainment of energy through the boundaries of the finite site of the base under short-term intense effect in the base are investigated

STRAIN CHARACTERISTICS OF SOILS AND THE METHODS OF THEIR DETERMINATIO

A method is proposed for determining the strain characteristics of soils under dynamic loads, based on the results of experiments on dynamic compression of soils in laboratory conditions on a device of dynamic loading and for solving a wave problem, the statement of which is identical to the statement of the experiment. With the proposed method, the dynamic and static compression moduli, the unloading modulus, the viscosity coefficient of loess soil in the range of seismic loads were determined in accordance with the elastic-viscoelastic soil model developed by G.M. Lyakhov

3-Benzyl-6-(2-chloro­benzo­yl)-1,3-benzoxazol-2(3H)-one

In the title compound, C21H14ClNO3, the benzoxazolone ring system is planar (r.m.s. deviation = 0.022 Å) and forms dihedral angles of 75.38 (10) and 65.92 (13)° with the mean planes of the chloro­benzoyl (r.m.s. deviation = 0.045 Å, excluding O atom) and benzyl (r.m.s. deviation = 0.023 Å) groups. The observed structure is stabilized by weak C—H⋯O hydrogen bonds and weak inter­molecular C—H⋯π inter­actions

Charge Ordering in Organic ET Compounds

The charge ordering phenomena in quasi two-dimensional 1/4-filled organic compounds (ET)_2X (ET=BEDT-TTF) are investigated theoretically for the $\theta$ and $\alpha$-type structures, based on the Hartree approximation for the extended Hubbard models with both on-site and intersite Coulomb interactions. It is found that charge ordered states of stripe-type are stabilized for the relevant values of Coulomb energies, while the spatial pattern of the stripes sensitively depends on the anisotropy of the models. By comparing the results of calculations with the experimental facts, where the effects of quantum fluctuation is incorporated by mapping the stripe-type charge ordered states to the S=1/2 Heisenberg Hamiltonians, the actual charge patterns in the insulating phases of $\theta$-(ET)_2MM'(SCN)_4 and $\alpha$-(ET)_2I_3 are deduced. Furthermore, to obtain a unified view among the $\theta$, $\alpha$ and $\kappa$-(ET)_2X families, the stability of the charge ordered state in competition with the dimeric antiferromagnetic state viewed as the Mott insulating state, which is typically realized in $\kappa$-type compounds, and with the paramagnetic metallic state, is also pursued by extracting essential parameters.Comment: 35 pages, 27 figures, submitted to J. Phys. Soc. Jp

Seismic Response of a Historical Unreinforced Masonry Building Damaged in the 2014 South Napa Earthquake

Several unreinforced masonry buildings damaged during the 2014 South Napa earthquake, California, USA, were investigated after the earthquake. The numerical analyses conducted on a representative example are presented in this paper. The building is the Sam Kee laundry building, the oldest stone commercial building in Napa, built in 1875. The geometry of the building was accurately captured by a laser scanner. Using this geometry information and material data available in literature for similar buildings, a finite element model of the building was developed according to the equivalent frame approach and was subjected to nonlinear time history analyses. The investigated building was closely located to a strong motion station on Main Street, Napa, California. This record was used as seismic excitation input to the numerical model. Results of the conducted analyses accurately predicted the observed damage in the building which consisted of shear cracks and shear damage in the south and north walls and failure of piers from the east wall. Analysis results are used to describe the reasons of the observed damage

ASSESSMENT OF STRESS-STRAIN STATE OF EARTH DAMS WITH ACCOUNT FOR GEOMETRICAL NONLINEARITY UNDER STATIC LOADS

Mathematical statement, methods and algorithms for assessing the stress-strain state (SSS) of earth structures are given in this paper taking into account geometric nonlinear soil strain under static influences. In the course of research, it was found that an account for geometrically nonlinear strain in soil leads to a noticeable change in the stress-strain state in high-rise structures and to an increase in all stress components. High concentration of stresses, which are the cause of strength damage in the zones of earth dams, is observed in the in the upper part of the coretransition zone contact point and in the upstream side