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This paper aims to improve the strength of soft clay soil using thermal treatment through a laboratory study that simulates the field application. The laboratory work consisted of preparing a soft clay (Cu = 14 kPa) inside a metal box (92.5 × 92.5 × 92.5) cm3. Boreholes of diameter 43 mm, with different lengths, spacing, and arrangements, were made inside the soil to work as a guide for heating pipes which connected to a controlled heating system. A novel heating system, using gas as a heat source, was developed and manufactured. After the end of the treatment periods, a load was applied until failure on a (20 × 20) cm2 square footing. Various parameter spacings (3, 4, and 5 times the outer diameter of the borehole), depths (1, 1.5, 2, and 2.5 times the width of the model footing), arrangements (square, circular, and triangular), and heating periods (2, 4, 6, 8, and 10 h) were investigated. The results showed the strength and behavior of the soil when subjected to the heated boreholes at different spacings, depths, and heating times, which were determined to be three times the outer diameter of the borehole, two times the width of the square footing, and eight hours, respectively, while the effect of the arrangement of the heated borehole casings was small. Also, a cone penetration probe (CPT) conducted on the heated soil showed that the unconsolidated shear strength (Cu) increased from 14 to 360 kPa and then decreased to 140 kPa (as an average with depth). In contrast, the average angle of internal friction (Ø) increased from 0 to 52 degrees and decreased to 16 degrees (as an average with depth) from the center of the heating model to the furthest point affected by heating. The EDS formula showed that components such as silicon, aluminum, and iron decreased at 300 °C and increased at 400 °C in the treated soils. The calcium content increased at 200 °C and then decreased sharply at 400 °C. The carbon percentage increased at 300 °C and decreased at 400 °C. The elemental proportions showed little change or remained stable at temperatures between 400 °C and 600 °C. [ABSTRACT FROM AUTHOR]

Batter or raker piles are piles driven at an inclination with a vertical to resist large inclined or lateral forces. Many structures like offshore structures and towers are subjected to overturning moments due to wave pressure, wind load, and ship impacts. Therefore in such structures, a combination of the vertical and batter piles is used to transfer overturning moments in compression and tension forces to the foundation. This paper presents a three-dimensional finite element analysis using PLAXIS 3D software to study the battered pile's behavior under the effect of pullout load. Several variables that influence the pile tension capacity embedded in sandy soil are investigated. The pile models are steel piles embedded in the dense sand at different batter angles (0, 10, 20, and 30) degrees with two embedment ratios, L/d (15 and 20). To clarify the pile shape's influence on a pullout capacity, two shapes are used, a circular pile with a diameter equal to 20 mm and a square pile with a section of 15.7×15.7 mm. These dimensions are chosen to achieve an equal perimeter for both shapes. The numerical results pointed that the pile pullout capacity increases with the increasing of the batter angle and embedment ratio, and the maximum values are marked at a batter angle of 20o. The shape of the bending moment profile is a single curvature, and the peak values are located approximately at the midpoint of the battered pile, while a zero value is located at the pile tip and pile head.

Ring footings are widely used as a foundation for water tanks, television antennas, silos, chimneys, oil storage tanks, etc. This paper is conducted to study the ring footing model's experimental cyclic behavior and circular footing resting on sandy soil reinforced with geocell. A group of ninety-six test models has been tested to investigate shallow footings' behavior beneath a cyclic loading of various loading rates. Four shapes of footing sand with three relative densities, two embedment depths of footing, two loading rates, and two widths of geocell were used. It was founded that as the footing depth increases, the settlement of soil due to cyclic loading decreases. Generally, when other variables are maintained to be the same, the footing bearing capacity increases when the foundation depth increases. The footing rebounds to some degree during the decay period of the load. The presence of geocell at the footing depth equals 100 mm will provide more improvement in all footing models more than using it at the surface, especially in ring 2 where the radius ratio is 0.4.

This paper introduces an experimental study to clarify the response of steel pile models exposed to the cyclic loading. Thirty six models of two types of steel piles are tested (open ended pile and H-pile) with lengths equal to (30, 40, and 50) cm. Three diameters (2.5, 3.5, and 4.1) cm for open ended pipe pile and three flange widths (2.6, 3.6, and 4.4) cm for H-pile are investigated. Jacking technique is employed to installed piles models in dry sandy samples with two different relative densities (60% for medium sand 80% for dense sand). It is found that the pile geometry (diameter and length) with sand density have a high impact on the number of cycles. Analysis of results showed that increasing of pile diameter and relative density cause a reduction in the number of cycles when the length of steel pile models are fixed while variety of diameters of open ended pipe pile has a small effect on the number of cycles. It was found that pipe piles with open ended have more resistance to the cyclic loading compared with H piles under the same geometric conditions (pile diameter, embedded length and sand density) especially in medium sand. Finally, if the testing conditions are the same, number of cycles is decreased with increasing in amplitude loading

The capabilities of geographical system and their spatial analysis is considered the most appropriate tools to enhance pavement management operations, with features such as graphical display of pavement condition. In Iraq, most of transportation agencies do not have a tool that is used as a database for road deteriorations, so there is a need for road surveying and storing the collected information in GIS to know the condition of every road with details. Furthermore, these data can be used for maintenance process and estimation of prior cost. This research has been carried out to estimate of flexible pavement condition through visual surveys using the Pavement Condition Index (PCI) method; so it can provide an easy way to calculate the PCI based on GIS data with Micro PAVER software 5.2. Al-Amarah Street, which is internal road in Al-Kut city in the eastern part of Iraq, is used as a case study. The average pavement condition index of the selected case study is found to be “64” using Micro PAVER 5.2 software which mean “Fair” pavement condition. Arc Map 9.3 has been applied in this study to make an integrated maintenance system for each road in the region demonstrating the annual road deteriorations and the resulting change in the PCI values which occurs every year. The study provides an easy and simplified way of presentation the details of deteriorations on the satellite or the geographical map of the road in which each type of distress has been symbolized with specific sign and each PCI value has been represented with specific color.

The present research is concerned with predicting liquefaction potential and pore water pressure under the dynamic loading on fully saturated sandy soil using the finite element method by QUAKE/W computer program. As a case study, machine foundations on fully saturated sandy soil in different cases of soil densification (loose, medium and dense sand) are analyzed. Harmonic loading is used in a parametric study to investigate the effect of several parameters including: the amplitude frequency of the dynamic load. The equivalent linear elastic model is adopted to model the soil behaviour and eight node isoparametric elements are used to model the soil. Emphasis was made on zones at which liquefaction takes place, the pore water pressure and vertical displacements develop during liquefaction. The results showed that liquefaction and deformation develop fast with the increase of loading amplitude and frequency. Liquefaction zones increase with the increase of load frequency and amplitude. Tracing the propagation of liquefaction zones, one can notice that, liquefaction occurs first near the loading end and then develops faraway. The soil overburden pressure affects the soil liquefaction resistance at large depths. The liquefaction resistance and time for initial liquefaction increase with increasing depths. When the frequency changes from 5 to 10 rad/sec. (approximately from static to dynamic), the response in displacement and pore water pressure is very pronounced. This can be attributed to inertia effects. Further increase of frequency leads to smaller effect on displacement and pore water pressure. When the frequency is low; 5, 10 and 25 rad/sec., the oscillation of the displacement ends within the period of load application 60 sec., while when ω = 50 rad/sec., oscillation continues after this period. [ABSTRACT FROM AUTHOR]