Thermal Transfer Analysis of a Freezing Soil Medium with an Embedded Pipeline

This paper conducted the unsteady state heat transfer analyses, using the commercial code ABAQUS, for a freezing granite soil medium with an embedded pipeline in the closed system. The several physical values for granite soil of South Korea at various subzero temperatures were determined in laboratory tests. These studies were focused on the development of a computational scheme by applying the effective heat capacity model to the numerical procedures for predicting the temperature profiles along a buried pipeline and the frozen penetration depth. The proposed model took into consideration the phase-change effect of in situ pore water in the frozen fringe. A comparison of results obtained by the proposed model and the actual performances was valuable in establishing a level of confidence in the application of introduced theory.     

Tied-Back Excavations in Alluvial Soil of Taipei

In this paper we present monitored results of three tied-back excavations carried out in the alluvial soil of Taipei. All three cases involved large excavations and were supported by a diaphragm wall and multilevel tieback anchors. Based on the anchor loads measured during excavation, the apparent lateral pressure diagrams are calculated following Terzaghi and Peck’s method. It is found that the apparent lateral pressures increase approximately linearly with the depth. As the excavation reaches its final depth, the apparent lateral pressure diagrams tend to converge for the cases studied here. The measured lateral pressure diagrams for these tied-back excavations are close to the summation diagrams of groundwater pressure and lateral pressure calculated from the method of Terzaghi and Peck in 1967 or Tschebotarioff in 1973 for sandy soil but with a minor difference. The dominant sandy soil layer and groundwater pressure played a major role in determining the anchor load diagrams. The measured lateral wall movement for these tied-back excavations is found to be similar to that of cross-lot braced excavations in alluvial soil of Taipei both in magnitude and in profile.     

Calibration of Electromagnetic Induction for Regional Assessment of Soil Water Salinity in an Irrigated Valley

Electromagnetic instruments are increasingly being used for in situ analysis and mapping of soil salinity in irrigated soils. This study develops calibration models for salinity assessment over regional scales on the order of tens of thousands of hectares. These models relate apparent soil electrical conductivity measured with the EM-38 electromagnetic induction meter (Geonics Ltd.) to traditional laboratory-measured saturated paste electrical conductivities (ECe). The study area is located in the Lower Arkansas River Valley, Colo. and is divided into two regions. At each of 414 randomly selected calibration sites, an EM-38 reading was taken and multiple soil samples were extracted for analysis. The sites chosen have soil ECe values ranging from 1?to?18?dS/m, gravimetric water contents (WC) from 0.02 to 0.4, and textures ranging from sands to clays. The best model for predicting soil ECe in both study regions is bivariate nonlinear and includes EM-38 vertical readings (EMV) and WC as covariates. Uncertainty in the calibration equations is addressed and tests are conducted at 48 independent sites. Results indicate that, while uncertainty is considerable in regional scale surveys, electromagnetic instruments can be calibrated for rapid reconnaissance of soil water salinity, providing reasonably accurate identification of salinization categories.     

Identifying Critical Sources of Bridge Deterioration in Cold Regions through the Constructed Bridges in North Dakota

This paper presents the performance of constructed bridges in cold regions through examining the bridges in North Dakota that is one of the coldest regions in the United States. Unique approach of a combined multiple regression and geographic information system technology is employed to evaluate the performance and to identify the critical sources affecting deterioration of the 5,289 bridges sampled from the National Bridge Inventory database inspected between 2006 and 2007. Typical parameters examined include physical, material, and environmental factors associated with the existing bridges. The importance of maintenance and repair is highlighted. Traffic volume significantly influences the level of deterioration of the bridge decks. Year built is the most significant contribution to the structural deficiency of the bridges, followed by structural characteristics and traffic volumes. The presence of water particularly influences the deterioration. Concrete bridges are more durable than steel bridges. Truss systems may not be recommended for cold regions.     

Wedge Failure Analysis of Soil Resistance on Laterally Loaded Piles in Clay

A fundamental study of pile-soil systems subjected to lateral loads in clay soil was conducted by using experimental tests and a lateral load-transfer approach. The emphasis was on an improved wedge failure model developed by considering three-dimensional combination forces and a new hyperbolic p-y criterion. A framework for determining the p-y curve on the basis of both theoretical analysis and experimental load test results is proposed. The proposed p-y method is shown to be capable of predicting the behavior of a large-diameter pile under lateral loading. The proposed p-y curves with an improved wedge model are more appropriate and realistic for representing a pile-soil interaction for laterally loaded piles in clay than the existing p-y method.     

Spatial Variation of Sediment Sulfate Reduction Rates in a Saline Lake

Devils Lake in North Dakota is a terminal, multibasin, saline lake with an overall surface area that is currently approximately 44,520?ha (110,000?acres). Lake elevation has increased by more than 7?m within 10?years, and vast areas of prairie and cropland have been flooded. The lake is rich in sulfate, and water column sulfate concentrations are relatively uniform within each of the five major basins, but increase from 3.1?mM (300?mg/L) in West Bay to 31?mM (3,000?mg/L) in East Devils Lake. Sediment cores were collected from three of the basins at different water depths, and used in laboratory studies to evaluate the spatial distribution of sulfate-reducing bacteria (SRB) activity in the lake sediments. The high sulfate concentrations within the experimental sediment cores suggest that the activity of SRB is limited by the availability of suitable electron donors rather than by the availability of sulfate and that SRB activity can be defined by a zero-order volumetric rate constant (K0). Experimentally determined K0 values ranged from 11?to?88?mmol SO42? m?3?day?1. The water depths from which sediment cores were collected in Devils Lake are related to the elapsed time since inundation by the rising lake level. It was found that time since inundation influences the observed K0 value. Mean K0 values for cores from an average depth of 4.8?m (submergence time of about 5?years), and 9.4?m (submergence time of about 28?years) were 62 and 17?mmol SO42? m?3?day?1, respectively. The significant difference (two-tailed t-test, p<0.05) suggests that SRB activities in the Devils Lake sediments change with submergence times. A uniform sulfate reduction rate applied to all Devils Lake sediments is therefore only a crude approximation of reality.     

Effect of Loading in Soil Slurry-Sequencing Batch Reactors on Biosurfactant Production and Foaming

A soil contaminated with diesel fuel (DF) was treated in 8-L soil slurry sequencing batch reactors with 10-day retention times and different volumetric loadings: 5, 10, and 50% of the reactor volume per cycle. Concentrations of DF, DF-degrading microorganisms, and biosurfactant were measured, with emulsification capacity (EC), foam thickness, and O2 uptake. Foaming coincided with nonzero values of EC, a measure of free (i.e., non-DF-bound) surfactants. Higher surfactant levels increased DF emulsification and foaming and reduced DF stripping. Concentrations of Candida tropicalis, Brevibacterium casei, Flavobacterium aquatile, Pseudomonas aeruginosa, and Pseudomonas fluorescens were determined. Biosurfactant production and DF degradation increased with increased loading. Biosurfactants exceeded the critical micelle concentration early in the cycle but were completely degraded by the cycle’s end. Orders-of-magnitude differences in effluent concentrations of individual species were observed. Culture-based counts of surfactant-producing species (C. tropicalis, P. aeruginosa, P. fluorescens) relative to total counts increased from 21 to 86% as loading increased from 5 to 50%.     

Analysis of Laterally Loaded Piles in Soil with Stiffness Increasing with Depth

This article reports a variational solution and its spreadsheet calculation procedure for the analysis of laterally loaded piles in a soil with stiffness increasing with depth. The aim of the paper is to provide solutions that can be used simply with recourse only to spreadsheet calculation to solve the displacement and bending moment of laterally loaded piles, so that they can be easily applied in practice as an alternative approach to analyze the response of laterally loaded piles.     

Study of Recent Building Failures in the United States

A total of 225 building failures in the United States from 1989 to 2000 were recorded in this study. The result shows that failures of low-rise buildings constitute about 63% of all cases, followed by multistory buildings as a distant second. In terms of their functions, apartments are the most frequent to fail. External events and construction and maintenance deficiencies have been identified as the most frequent principal causes. External events include rain, wind, snow, vehicular impact, and collision. Construction deficiencies encompass improper renovation, unplanned demolition, poor workmanship, and unsafe excavation operations. Maintenance deficiencies are associated with building deterioration that was overlooked and improperly maintained. A comparative analysis conducted between this study and two previous studies indicates an inclined trend of relative failure occurrences of low-rise and multistory buildings. The study also suggests that, despite the recent enhancement of information technology, current sources of information are still incomplete. The creation of new complete databases, further improvement of information sources, and their dissemination through the Internet are deemed essential to prevent building failures from recurring.     

The state of psychotherapy in the United States.

This article stems from the 2003 Society for the Exploration of Psychotherapy Integration (SEPI) international panel on the state of psychotherapy. I am pleased to be included in the printed version of this discussion. The state of psychotherapy in the United States is a huge topic. Does psychotherapy reach enough people and meet enough needs? What changes have occurred in response to political, financial, or cultural influences? Many of the subheadings deserve entire conference meetings to thoroughly consider the issues. However, in a time of significant transition for psychotherapy, a broad look at trends and influences may help keep the field of psychotherapy on a desired course. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Production of psychology doctorates in the United States.

Presents an analysis of data provided by Rechtenwald (1961) on psychology doctorates. His data, taken from "Statistical Abstract of the United States, originated with the U.S. Office of Education, as a portion of its "Earned Degrees Conferred" series. Disparities in data are examined, including discrepancies between the USOE data and the OSP data for the period 1949-56. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis of Recent Bridge Failures in the United States

Over 500 failures of bridge structures in the United States between 1989 and 2000 were studied. The age of the failed bridges ranged from 1 year (during construction) to 157 years, with an average of 52.5 years. The most frequent causes of bridge failures were attributed to floods and collisions. Flood and scour, with the major flood disaster in 1993, contributed to the frequency peak of bridge failures (almost 53% of all failures). Bridge overload and lateral impact forces from trucks, barges/ships, and trains constitute 20% of the total bridge failures. Other frequent principal causes are design, detailing, construction, material, and maintenance. Comparison made among three periods of similar studies (1977–1981, 1982–1988, and 1989–2000) revealed almost similar trends, with most failures occurring during the bridge’s service life. Also, human-induced external events occurred frequently in all three periods, but were most dominant in the first and third periods. Technological advances in information systems have a great impact on data collection and analysis.     

Military psychology in the United States of America.

"Between World War I and World War II, there was almost no interest of American psychologists in military problems, perhaps because there was almost no interest of the military in gaining the assistance of psychologists." The 1948 APA Directory identifies 98 psychologists as working for the Departments of Defense, Army, Air Force, or Navy. "This represents about 2% of the 5,047 members of the APA at that time. In the 1957 APA Directory, I have counted 729 psychologists who are listed as working for agencies of the military departments." This represents "almost 5% of the 15,000 members listed in the 1957 APA Directory." Various branches of military psychology within the Army, the Navy, and the Air Forces are indicated "to give appropriate emphasis to the great diversity of uses to which psychologists are put and to the consequently great variety of projects these agencies must, by their very titles and associations, engender." It also provides a statement "about how military psychology is organized within the Armed Forces in the States." The roles of the psychologist in military personnel management and in weapons development are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of Downdrag on Piles and Pile Groups in Consolidating Soil

Development of pile settlement (downdrag) of piles constructed in consolidating soil may lead to serious pile foundation design problems. The investigation of downdrag has attracted far less attention than the study of dragload over the years. In this paper, several series of two-dimensional axisymmetric and three-dimensional numerical parametric analyses were conducted to study the behavior of single piles and piles in 3×3 and 5×5 pile groups in consolidating soil. Both elastic no-slip and elasto-plastic slip at the pile–soil interface were considered. For a single pile, the downdrag computed from the no-slip elastic analysis and from the analytical elastic solution was about 8–14 times larger than that computed from the elasto-plastic slip analysis. The softer the consolidating clay, the greater the difference between the no-slip elastic and the elasto-plastic slip analyses. For the 5×5 pile group at 2.5 diameter spacing, the maximum downdrag of the center, inner, and corner piles was, respectively, 63, 68, and 79% of the maximum downdrag of the single pile. The reduction of downdrag inside the pile group is attributed to the shielding effects on the inner piles by the outer piles. The relative reduction in downdrag (Wr) in the 5×5 pile group increases with an increase in the relative bearing stiffness ratio (Eb/Ec), depending on the pile location in the group. Compared with the relative reduction in dragload (Pr), Wr at the corner pile is less affected by the group interaction for a given surcharge load. This suggests that the use of sacrificing piles outside the pile group will be more effective on Pr than on Wr. Based on the three cases studied, the larger the number of piles in a group, the greater the shielding effects on Wr. Relatively speaking, Wr is more sensitive to the total number of piles than to the pile spacing within a pile group.     

Public understanding of climate change in the United States.

This article considers scientific and public understandings of climate change and addresses the following question: Why is it that while scientific evidence has accumulated to document global climate change and scientific opinion has solidified about its existence and causes, U.S. public opinion has not and has instead become more polarized? Our review supports a constructivist account of human judgment. Public understanding is affected by the inherent difficulty of understanding climate change, the mismatch between people's usual modes of understanding and the task, and, particularly in the United States, a continuing societal struggle to shape the frames and mental models people use to understand the phenomena. We conclude by discussing ways in which psychology can help to improve public understanding of climate change and link a better understanding to action. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Review of the redistribution of psychologists in the United States.

A table is provided indicating distribution of psychologists by state, during 1950 and 1960-61, and a growth index for the decade; a 2nd table indicates regional distribution of psychologists and growth index by region. "One conclusion seems quite definite. The geographic pattern of distribution and concentration of psychologists has shown considerable growth in the decade, but no real change in the pattern. There were in 1950 15 states above the national average in concentration of psychologists, and the District of Columbia, 16 units. Of these 11 were still above the national average in 1960-61 and no state had risen from below the national average in concentration in 1950 to above it in 1960-61. District of Columbia, New York, and California are home to over ? of all APA members." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Commonsense notions of unfairness in Japan and the United States.

The concept of fairness has been centrally situated within justice and legal discourses, yet some have suggested that a deeper understanding is possible by looking at the "injustice" end because those instantiations tend to be clear, concise, hot, passionate, insistent, and have primacy. In this cross-cultural work, the authors apply this suggestion by deconstructing instantiations of unfairness from American and Japanese samples of students and their parents. Although all major types of unfairness were invoked in both countries, significant differences emerged in the frequency distribution patterns and quantitative severity ratings of unfairness by culture; to a lesser extent, by generation within culture; and to a still lesser extent, by gender. Why discriminatory treatment instantiations were significantly more salient for Japanese than American respondents (and why the reverse was so for misfortune instantiations) is discussed, along with foundational links of unfairness notions to communal relationships and society. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Factors Affecting the Use of Precast Concrete Systems in the United States

The use of precast concrete systems offers several advantages such as speedy erection, higher quality, lower project cost, better sustainability, and enhanced occupational health and safety. In spite of these advantages, the share of precast concrete systems in the U.S. building construction market is very low. The factors behind this low market share are discussed in several studies. This study aims to identify the current factors that affect the use of precast concrete systems, compare them with the ones that prevailed in 1995, and figure out what has changed through the last 11?years in the American precast concrete industry. The findings of an extensive survey indicate that most of the dominating barriers to the extensive use of precast concrete systems in 1995 are either eliminated or drastically reduced, while some of them still prevail. Practitioners should be well informed about the factors that affect the use of precast concrete systems if these systems are to be used more extensively.