Tire shreds and tire shred  soil mixtures can be used as alternative backfill material in many geotechnical applications. The reuse of tire shreds may not only address growing environmental and ec...

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Behaviour of tire shred - sand mixtures

An experimental investigation of the uplift behaviour of relatively large scale model circular plate anchors up to 400 mm in diameter embedded in loose, medium-dense, and dense dry sand is describe...

Experimental investigation of the uplift behaviour of circular plate anchors embedded in sand

Helical piles are increasingly used to support and rehabilitate structures subjected to both tensile and compressive axial loads This paper presents a detailed investigation into the axial perform

Axial testing and numerical modeling of square shaft helical piles under compressive and tensile loading

This paper investigates the resultant strength and ductility behavior when randomly distributed palm fibers are used to reinforce silty-sand soils. The composite soils were tested under laboratory conditions and examined for unconfined compression strength (UCS), California Bearing Ratio (CBR) and compaction test. The results indicated that; the maximum and residual strengths, orientation of surface failures, ductility and the stress-strain relationship of the specimens were substantially affected by the inclusion of palm fibers. A significant result was the determination that the sliding failure strength controlled the failure of the specimens rather than the rupture failure strength. Overall it was found that reinforced soil using palm fibers as the primary reinforcement are beneficial engineering materials and could potentially be used more often, though additional field use and testing should be carried out. Given the current concern over the environment and greenhouse gas emissions, strengthening soil through the use of natural materials (in this case palm fibers) and the promotion of the cultivation of palm groves is one way that engineers and designers can contribute to a greener earth. Add to this the fact that the date palm is one of the most cultivated tree crops in the world with a worldwide distribution of around 100 million palms distributed in 30 countries including the Middle East, Asia, Africa, North America, Mediterranean countries and Australia in a bountiful resource that is available in many places where high technology engineering practices are either not available or too expensive. The use of the date palm for soil reinforcement means that in many areas of the world there is a readily available, effective local source of material for road foundation construction.

/pdf/strength-and-ductility-of-randomly-distributed-palm-fibers-2lv8wszbgt.pdf

Strength and Ductility of Randomly Distributed Palm Fibers Reinforced Silty-Sand Soils

The results of a study to quantify effects of time on pile capacity are presented herein. The main focus of this paper is to present results from a database developed from various pile tests reported in the literature and to present some observations based on the pile test data. Both sands and clays are shown to experience setup. A database containing 80 pile load tests (both static and dynamic) was collected and sorted into three groups according to the primary subsurface profile: sands, clays, and mixed soil. Capacity-versus-time relationships are plotted for each soil type, but particular attention is given to the increase in capacity of pile in sand with time. It is shown that the load test results can provide an upper-bound estimate and a lower-bound estimate. Estimating the effect of time on pile capacity in sand can be important for reuse of existing piling and also can be helpful for quantifying just how much to expect capacity to increase with time if pile load tests show that capacities are comi...

Measured time effects for axial capacity of driven piling

Experimental and theoretical investigations on the behavior of single‐screw helical anchors in sand are presented. A testing program included 56 tests conducted on five model anchors installed in dense, medium, and loose dry sands. A sand‐placing technique was developed and utilized over the testing program in order to achieve the predetermined unit weight. The experimental setup was instrumented to allow the measurement of the pullout load, the upward displacement of the anchor, and the deflection of the sand surface. It was observed that the failure mechanism as well as the pullout load varied with the installation depth of the anchor and the angle of shearing resistance of the sand. A mathematical model is developed using the limit‐equilibrium method of analysis and the observed failure mechanism of the anchor from the present experimental work. Based on experimental results, a simple equation is proposed to introduce the degree of shear mobilization on the coefficient of passive earth pressure. Compar...

Uplift behavior of screw anchors in sand. i: dry sand

https://www.jstage.jst.go.jp/article/sandf1972/31/2/31_2_77/_pdf

Installation torque of screw anchors in dry sand

An investigation into the performance of single vertical screw anchors installed in sands is presented. Models were developed employing the limit equilibrium method of analysis to predict the uplif...

Ultimate pullout resistance of single vertical anchors

Experimental and theoretical studies on the torque required to install screw anchors in sand are presented. Tests were conducted on five models of screw anchors with different geometry to study the...

Experimental and theoretical studies on installation torque of screw anchors

Experimental investigations on the performance of single and groups of vertical screw anchors installed in dense, medium, and loose sands are presented. An experimental setup was instrumented to allow the measurement of the total pullout load, upward displacement, sand surface deflection, and stress development in the sand layer during all phases of testing. A sand placing technique was developed and utilized over all the testing program to ensure reproducibility of the predetermined unit weight. Stresses measured within sand deposits indicated that the tested sands were overconsolidated due to the application of mechanical compaction. Special tests were conducted on colored–layered sand to define the nature of the failure mechanism. The results of these tests, together with the measurements of the deflection of the sand surface, were employed to establish the shape of the rupture surface which could be represented by a segment of a logarithmic spiral. Groups of three, four, six, and nine anchors were tes...

Ashraf Ghaly

Papers

Uplift behavior of screw anchors in sand. i: dry sand

Installation torque of screw anchors in dry sand

Ultimate pullout resistance of single vertical anchors

Experimental and theoretical studies on installation torque of screw anchors

Model investigation of the performance of single anchors and groups of anchors