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Showing papers on "Embedment published in 1985"


01 Dec 1985
TL;DR: In this paper, the uplift capacity of helix anchors in sand is investigated and the experimental results indicate that a cylindrical soil failure surface develops below the top helical shaped plate during pullout.
Abstract: Results of field and laboratory investigations of the uplift capacity of helix anchors in sand are presented. Equipment and instrumentation were used to measure uplift load, anchor deflection and sand surface deflections. Instrumentation was also used in the laboratory tests to monitor movements within the soil mass during uplift loading. The experimental results indicate that a cylindrical soil failure surface develops below the top helical shaped plate during pullout. Above the top plate the failure surface is dependent on depth of anchor embedment. Anchor installation and soil relative density also influence failure surface development. A method for estimating uplift capacity based on results of laboratory study and generally accepted soil mechanics principles is presented.

107 citations


Journal ArticleDOI
TL;DR: In this article, a simple method to compute the dynamic stiffnesses and damping coefficients of arbitrarily shaped rigid foundations embedded in a reasonably homogeneous and deep soil deposit and subjected to harmonic vertical excitation is developed.
Abstract: A simple method to compute the dynamic stiffnesses and damping coefficients of arbitrarily shaped rigid foundations embedded in a reasonably homogeneous and deep soil deposit and subjected to harmonic vertical excitation is developed. The method is based on an improved understanding of the physics of the problem, substantiated by the results of extensive, rigorous parametric studies, including several analytical results compiled from the literature. The results are applicable to both saturated and unsaturated soils, a variety of cross‐sectional shapes, and a wide range of embedment depths and types of contact between the vertical sidewalls and the surrounding soil. A numerical example illustrates the applicability of the method. It is also shown that the method constitutes a significant improvement over current practical procedures, such as the “equivalent circle” approximation.

62 citations


Journal ArticleDOI
TL;DR: In this article, a model system of sisal slivers embedded in cement and protruding from one end of the cement matrix was used to investigate fracture and pull-out of woodpulp fibres.

34 citations


Journal ArticleDOI
TL;DR: For anchors embedded in cohesive soil, the uplift capacity remains almost constant when the ratio of anchor embedment depth to anchor diameter (D/B) increases above about 4.5 as mentioned in this paper.
Abstract: For anchors embedded in cohesive soil, the uplift capacity remains almost constant when the ratio of anchor embedment depth to anchor diameter (D/B) increases above about 4.5. The uplift capacity o...

28 citations


Journal ArticleDOI
TL;DR: In this paper, the dynamic response of a cylindrical tunnel embedded in a semi-infinite elastic medium is analyzed, where the tunnel is assumed to be infinitely long, noncircular in cross section, and lying parallel to the plane-free surface of the medium.
Abstract: The dynamic response of a cylindrical tunnel embedded in a semiinfinite elastic medium is analyzed. The tunnel is assumed to be infinitely long, noncircular in cross section, and lying parallel to the plane‐free surface of the medium. The problem considered is one of plane strain, in which it is assumed that the waves are propagating perpendicular to the axis of the tunnel. Since this problem cannot be solved exactly except when the tunnel is circular, a numerical technique that combines the finite element method with the eigenfunction expansions is used. Numerical results are presented for the cases in which the tunnel is disturbed by plane longitudinal (P), vertically polarized shear (SV) and Rayleigh (R) waves. It is shown that the dynamic amplifications of the displacements and stresses induced in the tunnel depend crucially on the properties of the surrounding soil, the depth of embedment and the frequency of the incident simple harmonic disturbance.

27 citations


Journal ArticleDOI
01 Aug 1985

9 citations


Journal ArticleDOI
TL;DR: Laterally unsupported steel beams of sufficient length may fail by elastic or inelastic lateral-torsional buckling as mentioned in this paper, and the fundamental equations governing elastic lateral -torsion buckling, taking in...
Abstract: Laterally unsupported steel beams of sufficient length may fail by elastic or inelastic lateral–torsional buckling. The fundamental equations governing elastic lateral–torsional buckling, taking in...

4 citations


Journal ArticleDOI
TL;DR: In this paper, an approximate analytical solution is developed for the effective seismic motions of cylindrical embedded rigid foundations having the two embedment cases as follows: Case 1, embedded in a viscoelastic surface layer with the foundation base resting on a much stiffer bedrock, Case 2; embedded in this paper.
Abstract: With the aid of currently available finite element method results, an approximate analytical solution is developed for the effective seismic motions of cylindrical embedded rigid foundations having the two embedment cases as follows: Case 1; embedded in a viscoelastic surface layer with the foundation base resting on a much stiffer bedrock, Case 2; embedded in a viscoelastic surface layer with the foundation base resting within the surface layer. The characteristics of the solution are compared with the results of the laboratory tests by shaking table and also with the responses observed at an actual embedded foundation during an earthquake, where the original data were available by other investigators. It is found from the comparisons that the solution developed in this paper well agrees with the experimental and observed data.

3 citations


Journal ArticleDOI
TL;DR: In this article, the effects of various parameters on the dynamic response of underground tunnels are investigated using finite element techniques in order to idealize the tunnel and the surrounding soil, and it is found that some of the main parameters which influence the response of a tunnel are: soil stiffness and layering, depth of embedment and the thickness of the concrete, protective slab Vertical acceleration are also affected by the stiffness of the tunnel.

2 citations



01 Jan 1985
TL;DR: In this article, a new lightweight PVC pipe, consisting of a smooth inner wall and a corrugated outer wall, has been introduced in the U.S. sanitary sewer market in 4 through 10 in. diameters.
Abstract: A new lightweight PVC pipe, consisting of a smooth inner wall and a corrugated outer wall, has been introduced in the U. S. sanitary sewer market in 4 through 10 in. diameters. Field burial tests were conducted to investigate its structural performance. Pipe deflections due to compaction of embedment soil were minor. All responses appear to have stabilized after 1 year with pipe ring deflections less than 3. 5% in all but the uncompacted clay condition. Predicted initial deflections by traditional methods agree fairly well with measurements. Based on 1 year data, long-term deflections are somewhat overestimated by traditional deflection lag concepts. Results show that this pipe installed as described in ASTM D 2321 will exhibit acceptable deflections.

01 Feb 1985
TL;DR: It was determined that for the 3/4-inch-diameter ASTM A-307 threaded rods installed with resin capsule anchors and under conditions tested, allowable tensile design loads of 6300 pounds for rods embedded four inches are acceptable.
Abstract: The purpose of this study were to determine the minimum embedment depths required for commercially available 3/4-inch-diameter polyester resin capsule anchor systems to withstand direct tensile desing loads of 6300 and 3150 pounds with acceptable short-term creep over a 100-hour time period. Short-term creep behavior was determined for thirty-six 3/4-inch-diameter resin capsule anchors and is presented and discussed. Four series of tests were conducted. Nine threaded rods in each of the first and third test series were installed in 5-inch-deep holes at 4 3/8 and 2 3/4-inch edge distances, respectively. Creep was monitored while the rods were subjected to a 9450-pound sustained axial tensile test load. In the second and fourth test series, nine threaded rods in each test series were installed in 4-inch-deep holes at 4 3/8 and 2 3/4-inch edge distances. Creep was monitored while the rods were subjected to a 4725-pound sustained axial tensile test load. It was determined that for the 3/4-inch-diameter ASTM A-307 threaded rods installed with resin capsule anchors and under conditions tested, allowable tensile design loads of 6300 pounds for rods embedded four inches are acceptable. Short-term creep values for all systems tested were suustantially lower than the maximum permitted. All three brands of resin capsule anchors that were tested performed satisfactorily. (Author)

Patent
05 Jul 1985
TL;DR: In this paper, a method of bonding propellant to the insulation in a motor chamber by use of an adhesive and powder granule layer was proposed, which was shown to be effective in the case of a single motor.
Abstract: A method of bonding propellant to the insulation in a motor chamber by usef an adhesive and powder granule layer.