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Showing papers on "Embedment published in 1974"


Journal ArticleDOI
TL;DR: In this article, an approximate analytical approach is presented which makes it possible to consider soil properties and footing embedment in the analysis of the response of structures to external excitation such as wind and earthquake.
Abstract: An approximate analytical approach is presented which makes it possible to consider soil properties and footing embedment in the analysis of the response of structures to external excitation such as wind and earthquake. The approach is based on modal analysis and the definition of stiffness and damping due to soil pertinent to each vibration mode. The approach also facilitates the analysis of coupled motions of a footing alone. The analysis of a tall chimney for the effects of gusting wind, vortex shedding and earthquake is used as an example.

113 citations


Journal ArticleDOI
TL;DR: In this paper, a number of field load tests for piles in cohesionless soils are analyzed using the finite element method, and a modification in the formula is suggested to account for the reduction in bearing capacity with length of embedment.
Abstract: A number of field load tests for piles in cohesionless soils are analyzed using the finite element method. Satisfactory correlations are obtained between numerical predictions and observations for pile movements versus applied load, and division of total load into point and skin friction components. Computed bearing capacities using various failure criteria show good agreement with those evaluated from a formula based on limit equilibrium and from field data. Distributions of normal and shear stresses along the pile wall, and coefficient of lateral earth pressure, and significance of stress paths in the stress-strain law are examined. Effects of diameter and length of embedment on bearing capacity, particularly at higher lengths of embedments, are found to differ from those given by the limit equilibrium formula. A modification in the formula is suggested to account for the reduction in bearing capacity with length of embedment.

67 citations


Patent
23 Dec 1974
TL;DR: In this paper, a screw-type anchor device for securement into masonry structures is proposed, where a sharp crested helical thread, preferably with tapering crest diameter, is formed along the shank and helical protuberances forming guide means are spaced between adjacent convolutions of the thread.
Abstract: A screw type anchor device for securement into masonry structures. A sharp crested helical thread, preferably with tapering crest diameter, is formed along the shank and helical protuberances forming guide means are spaced along the shank between adjacent convolutions of the helical thread. Notches are formed on the crests of the helical thread along the length of the shank to facilitate embedment of the crests in the walls of a performed bore in the masonry structure.

37 citations


Patent
04 Feb 1974
TL;DR: Improved membrane package construction is shown in this paper in which nonporous, rigid embedment is provided for the edges of each membrane and the membrane surface area immediately adjacent each manifold location.
Abstract: Improved membrane package construction is shown in which nonporous, rigid embedment is provided for the edges of each membrane and the membrane surface area immediately adjacent each manifold location. In addition, for construction embodying immobilized liquid membranes, all edges of each membrane assembly and surface area immediately adjacent the edges are similarly embedded. It has been found that pressure differences of at least 300 psi between feed and sweep gases can be accommodated with the improved construction of this invention.

22 citations



Patent
03 May 1974
TL;DR: In this article, a pair of plates, each having a generally channel-shaped configuration with a flange at one end, are used to embed a plurality of elongated nail-like teeth into the respective frame members.
Abstract: The device includes a pair of plates, each having a generally channel-shaped configuration with a flange at one end. The flanges have a plurality of elongated nail-like teeth struck therefrom for embedment into the respective frame members. The channel-shaped members are telescopically received one within the other at the ends remote from the flanges and secured whereby the frame members are spaced one from the other at selected distances. The upper flanges of the elements are arcuately contoured and provide clearance between the upper flanges and a seat and spring underside to permit deflection of the seat construction toward the flanges when an individual is seated.

12 citations


01 Sep 1974
TL;DR: In this article, the anchor plate design utilizing shallower reinforcing steel embedment reduced the ductility of the system, at stress levels exceeding yield stresses, by limiting the length of bar available for plastic elongation after the occurrence of bond breakdown.
Abstract: Results of nineteen pullout tests conducted on #18, #14 and #11, Grade 60 steel reinforcing bars (ASTM A615-68) to evaluate end anchorage provided by an attached steel end-plate are reported. The effects of group action and low cycle dynamic loading are also reported. Short embedment lengths for anchored bars resulted in greater loaded-end slips than those realized by unanchored bars embedded in accordance with current allowable bond stresses. These slips, however, were less than the "critical" value of 0.010 of an inch at an applied steel stress of 24 kips per square inch. The anchor plate design utilizing shallower reinforcing steel embedment reduced the ductility of the system, at stress levels exceeding yield stresses, by limiting the length of bar available for plastic elongation after the occurrence of bond breakdown. The use of an anchorage device on bars with short embedment lengths served to increase ultimate strength capability to that of a fully embedded, unanchored bar. Visible concrete crack patterns were not influenced by the use of anchor plates. Group-action test results indicated greater slip values at values at given stress levels when compared with single bar tests. Multiple bar pullout tests need to be performed on unanchored bars before the group-action phenomenon can be better evaluated. /FHWA/

11 citations


PatentDOI
04 Feb 1974
TL;DR: A propellant-actuated direct embedment anchor which utilizes simplified structural shapes and provides a rapid keying feature which allows the most efficient use of penetration energy is presented in this paper.
Abstract: A propellant-actuated direct embedment anchor which utilizes simplified structural shapes and provides a rapid keying feature which allows the most efficient use of penetration energy. The anchor system has two major parts; a launch vehicle and a projectile which include a piston and fluke. Two different fluke designs are provided to satisfy the realm of anticipated seafloor conditions (sand, clay, and rock). The flukes designed for said and clay are similarly configured plate-like projectiles which only differ in length. The fluke designed for rock anchoring is a three-fin, arrowhead-shaped projectile, specially configured to penetrate rock and resist a specified pull-out load. The launch vehicle consists of a launching system, a reaction vessel and a firing mechanism. The firing mechanism is comprised of a weighted touch-down rod with a square base pad and a safe-and-arm device. The sand and clay flukes use a quick-keying design to maximize efficiency and holding power after embedment.

8 citations


Book ChapterDOI
01 Jan 1974
TL;DR: In this article, the area of sediment property determination for direct embedment anchor design is considered specifically and two examples are given of possible uses of laboratory testing for sample disturbance correction and triaxial testing to investigate shear strength variation with sub-bottom depth and drainage.
Abstract: Engineering properties are needed primarily for engineering activities such as the design of foundations or anchors. They may be evaluated either through direct in situ testing or laboratory testing of samples. Laboratory testing provides a degree of flexibility, control, and economy not usually achieved with in situ testing and is, therefore, given primary attention in this paper. The area of sediment property determination for direct embedment anchor design is considered specifically and two examples are given of possible uses of laboratory testing. The first deals with quantitatively correcting laboratory strength results for sample disturbance. The procedure is evaluated using in situ and laboratory vane shear and residual pore pressure measurements. The second example deals with using triaxial testing to investigate shear strength variation with sub-bottom depth and drainage. Results of tests performed on “red” clay are given. The two examples given provide information for predicting the holding capacity of an embedment anchor. The examples are followed by a discussion of suggested additional research.

5 citations


Journal ArticleDOI
TL;DR: In this paper, a number of field load tests for piles in cohesionless soils are analyzed using the finite element method, and a modification in the formula is suggested to account for the reduction in bearing capacity with length of embedment.

4 citations


Patent
11 Apr 1974
TL;DR: A filamentary coiled electrode for a fluorescent lamp has a glass embedment at each end thereof to prevent coil entangling during lamp manufacture as discussed by the authors, which has been used to prevent lamp coil entanglement.
Abstract: A filamentary coiled electrode for a fluorescent lamp has a glass embedment at each end thereof to prevent coil entangling during lamp manufacture.

Patent
14 Mar 1974
TL;DR: In this article, a sheet of thermoplastic material is drawn to form a number of regularly spaced, transverse grooves along its whole length, with different sized sized grooves near each end on the same face and with flat grooves at intervals along that face.
Abstract: A sheet of thermoplastic material, is deep drawn to form a number of regularly spaced, transverse grooves along its whole length, with different sized grooves near each end on the same face and with a number of flat grooves at intervals along that face. The sheet is then cut into strips and these used as clamps for the parallel runs of looped electrical heater wire. The end grooves are used to clip lengths together and the flat grooves for width spaces. The whole can be rolled up for storage and layer in place for subsequent embedment.

Journal ArticleDOI
TL;DR: In this paper, the curvilinear nature of the relation S = f(P) was established for all cases of embedment of the plate and for loads substantially smaller than the limiting loads.
Abstract: 1. For the first time, the methods of the theory of elasticity and the theory of limiting equilibrium have been used for establishing the curvilinear nature of the relations S=f(P), which corresponds to the nature of this relation observed in tests with trial loads. 2. For all cases of embedment of the plate and for loads substantially smaller than the limiting loads, the contact pressure diagrams are similar to those obtained by the theory of elasticity, but do not exhibit any special characteristics under the edges. This agrees with the results of experimental investigations carried out in order to determine the contact pressures. 3. The plate displacements, for all other conditions being equal, and also for loads exceeding 0.3 MPa, depend substantially on the relative embedment of the plate in the soil or on the soil cohesion. 4. For practical analyses, the relation S=f(P) obtained by solution of the elastoplastic problem can be approximated by a hyperbola.