Design spectrum is known as an essential tool in earthquake engineering for calculation of maximum (design) responses in a structural system. SOIL-structure interaction (SSI), as a phenomenon of coupling of responses of a structure and its underlying SOIL, was explored after introduction of design spectra and has not been taken into account in developing a design spectrum traditionally. To consider the SSI automatically when doing a spectrum analysis, in this paper maximum response of a single degree of freedom system resting on a flexible base is determined under consistent earthquakes. Consistency of earthquakes is maintained by considering their magnitude, distance, local SOIL type, and return period. The latter parameter is accounted by the use of earthquake categories identified by their similar spectral values at short periods. Different types of SOILs and two categories of earthquakes regarding their distance, being near field and far field, are considered. The results are presented as smoothed design spectra. It is shown that SSI alters the response acceleration of buildings having up to about 10 stories and is ineffective for the rest. It has an increasing effect for the response acceleration of buildings up to about 5 stories.

Rapid urbanization and requirement of infrastructure, stable construction sites are not available. Therefore, there is a dire need for improvement of marginal SOILs to be used as a construction material. However, weak SOILs comprise of saturated clays, fine silts, and loose sand, which are susceptible to failure and pose problems of stability. Therefore, this research aims to study the strength and microstructural behavior of SOFT SOILs treated with nano-alumina (Al2O3) additive. In this study, Al2O3 of different percentages (0.5, 1.0, 1.5, and 2.0%) by dry weight of SOIL was added to a clayey SOIL and subjected to compaction and unconfined compression strength tests. The compaction tests showed that nano-Al2O3 (< 2.0%) stabilized SOILs exhibit higher unit weight and lower water content compared to untreated SOILs. This may be attributed due to the fact that nano-materials possess higher unit weight compared to untreated SOILs and these materials occupy the pore spaces in-between the SOIL grains, which reduce SOIL porosity and increase the shear strength. The unconfined compressive strength test on cured treated SOIL specimens showed a significant increase in shear strength on the addition of nano-alumina. The scanning electron microscopic analysis on untreated and treated SOIL specimens showed that untreated SOIL samples exhibit a compact array of clay grains and nano-material treated SOIL display closely packed and condensed fine structure, which authenticates an increase in shear strength. Thus, with the addition of Al2O3, there has been a significant improvement in the engineering properties of SOFT SOILs.

Background: Schizophrenia is one of the most important and disabling mental disorders in the world. Males and females are equally affected. Diagnosis is a very difficult problem in this disorder. Because the diagnostic systems such as ICD-IO and DSM-IV are mainly subjective, they are not valid and reliable. Essentially, in the future, we will need to more objective criteria in psychiatry especially in diagnosis of schizophrenia. Neurological SOFT signs are an example of these objective criteria. In this study we evaluated the prevalence of neurological SOFT signs in schizophrenic patients and compared it with the prevalence of these signs in other psychotic patients (except mood disorders with psychotic features) and normal subjects. Methods: We compared the neurological SOFT signs (sensory motor integration, motor. Coordination, consequent complex motor acts, primary reflexes, and eye movements) in 30 schizophrenic patients, 30 other psychotic patients (other than mood disorders with psychotic features) and 30 normal subjects. Diagnosis of schizophrenia and also other psychoses were based on DSM-IN criteria. Normal subjects have been selected form the staff of Roozbeh hospital randomly. Results: The difference between the means of motor coordination subscale of neurological SOFT signs in schizophrenia and other psychotic disorders (other than mood disorders with psychotic features) were significant (P value<0.04). There were no significant differences between the means of other subscales of neurological SOFT signs in two groups of patients. Conclusion: There are some disturbances of motor coordination subscale of neurological SOFT signs in patients with schizophrenia. It seems that, these disturbances are evidence of involvements of basal ganglia, motor cerebral cortex, and cerebellum. So it may be suggested that motor coordination as a marker can be used in differentiation between the schizophrenia and other psychotic disorders.

The environment prevalent in ocean necessitates the piles supporting offshore structures to be designed against lateral cyclic loading initiated by wave action. Such quasi-static load reversal induces deterioration in the strength and stiffness of the SOIL-pile system introducing progressive reduction in the bearing capacity associated with increased settlement of the pile foundation. To understand the effect of lateral cyclic load on axial response of single pile in SOFT clay, a numerical model has been developed. The theoretical results are compared with the available experimental results so as to validate the theory. This paper presents a brief description of the methodology developed, analysis and interpretations of the theoretical results obtained and the relevant conclusions drawn there from.

In this research, comprehensive studies have been carried out by laboratory and numerical modeling methods on the variables affecting SOIL improvement with SOIL-cement columns under different conditions of overhead and seismic loading. experimental studies are aimed at evaluating the performance of SOIL-cement columns in SOFT ground stabilization under two conditions of rigid footing and embankment fill, and based on the results, the numerical modeling was defined and validated (numerical modeling error less than 8%). The results of experimental studies showed that the stabilization by using SOIL-cement column under embankment fill condition caused more stabilization of SOFT SOIL compared to the condition of rigid footing and the amount of settlement decreased by 75% and 55% respectively. The results of numerical modeling showed that the use of SOIL-cement column has improved the seismic behavior of SOFT SOIL and the average of settlement under the loading of 5 major earthquakes has decreased by 54. 13% under rigid footing conditions and 71. 63% under embankment fill.

This paper presents the numerical analysis of seismic SOIL-pile-superstructure interaction in SOFT clay using free-field SOIL analysis and beam on Winkler foundation approach. This model is developed to compute the nonlinear response of single piles under seismic loads, based on one-dimensional finite element formulation. The parameters of the proposed model are calibrated by fitting the experimental data of large-scale seismic SOIL-pile-structure tests which were conducted on shaking table in UC Berkeley. A comparative evaluation of single piles shows that the results obtained from the proposed procedure are in good agreement with the experimental results.

The individual penetration of aggregates is an important problem in the construction of breakwater on SOFT seabed. Any overall resisting mechanism of the foundation could not be formed when aggregates are individually penetrating seabed. In this situation a large volume of breakwater material penetrates into bed. In design, "aggregate local penetration" control should be considered in addition to usual controls such as bearing capacity and settlement. In this paper, with the use of proposed laboratory method, penetration of aggregate into SOFT SOIL is investigated. In addition to laboratory studies, some breakwaters that constructed on SOFT seabed in the south coasts of Iran were studied. Finally, it has been concluded that fine mattress decreases penetration of aggregates. A relationship is proposed for determining mattress thickness.

In this paper, a study was carried out in order to estimate settlements and consolidation rates under embankments constructed on Moroccan SOFT SOILs. Settlement measurements in several embankments in High Speed Railway project between two Moroccan cities, Tangier and Assilah, were analyzed. The objective of this study is to estimate settlement values and settlement rates, with sufficient precision, in SOFT SOILs under embankment loadings. It was found that the elastic method using the pressuremeter modulus results in more accurate settlement values than the oedometric method. Furthermore, settlement rates could be determined with fair accuracy by using a correlation between the vertical coefficient of consolidation and the liquid limit, and also by considering an isotropic behavior of SOIL.