Embedment

About: Embedment is a research topic. Over the lifetime, 2441 publications have been published within this topic receiving 31444 citations.

Performance of steel pipe pile-to-concrete bent cap connections subject to seismic or high transverse loading: phase ii

Abstract: The response of a concrete filled, steel pipe pile-to-concrete pile cap connection subjected to extreme lateral loads was experimentally and analytically investigated in this project This connection is part of a bridge support system used by the Montana Department of Transportation that consists of a linear array of piles connected at the top by a concrete pile cap Five 1/2 size models of this connection were tested to failure under monotonically increasing and/or cyclic lateral loads The primary attribute of the connection that was varied between tests was the amount and layout of the reinforcing steel in the pile cap The depth of embedment of the pipe pile in the cap was held constant The first tests were done on lightly reinforced pile cap cross-sections, and failure occurred in the pile caps due to tensile cracking of the concrete and yielding of the reinforcing steel adjacent to the pile In subsequent connections, the amount of reinforcing steel in the cap was increased, and its arrangement was modified, until a plastic hinge occurred in the pipe pile before failure of the cap occurred The behavior of each connection was analyzed using hand calculations, strut and tie models, and solid finite element models The hand calculations accurately predicted the nature of the failure mechanism for each connection, but only poorly predicted the magnitude of the failure load The strut and tie models used in this investigation were created and analyzed using conventional structural analysis software The resulting models offered significant detail relative the response throughout the pile cap, but were unable to fully represent yielding of the reinforcing steel and the attendant redistribution of stresses within the cap Sufficiently promising results were obtained relative to predicting the load and location at which inelastic behavior will initiate, that this analysis methodology possibly should be pursued further Finally, though finite element models were not successfully used to model the damage cycle through cyclic loads as originally hoped, they did prove useful for extracting 3D information leading up to a state of permanent damage They also show immediate promise for modeling responses to monotonic load conditions, particularly for analysis where concrete damage is not the controlling failure mechanism

Nonlinear numerical simulation of punching shear behavior of reinforced concrete flat slabs with shear-heads

Abstract: This paper examines the structural response of reinforced concrete flat slabs, provided with fully-embedded shear-heads, through detailed three-dimensional nonlinear numerical simulations and parametric assessments using concrete damage plasticity models. Validations of the adopted nonlinear finite element procedures are carried out against experimental results from three test series. After gaining confidence in the ability of the numerical models to predict closely the full inelastic response and failure modes, numerical investigations are carried out in order to examine the influence of key material and geometric parameters. The results of these numerical assessments enable the identification of three modes of failure as a function of the interaction between the shear-head and surrounding concrete. Based on the findings, coupled with results from previous studies, analytical models are proposed for predicting the rotational response as well as the ultimate strength of such slab systems. Practical recommendations are also provided for the design of shear-heads in RC slabs, including the embedment length and section size. The analytical expressions proposed in this paper, based on a wide-ranging parametric assessment, are shown to offer a more reliable design approach in comparison with existing methods for all types of shear-heads, and are suitable for direct practical application.

Analysis of the behaviour of propped diaphragm walls in a deep clay deposit

Abstract: Modern techniques of excavation, including the use of structural diaphragm walls and top-down construction, provide effective methods to minimize deformations in the surrounding soil. However, for deep excavations and walls embedded in deep layers of soft clays, it is difficult to control soil movements. In these situations, reliable predictions of deformations are an important consideration in the design of the earth support system. This paper describes results of numerical experiments, based on non-linear finite element analyses and incorporating an effective stress soil model which describes observed aspects of soft clay behaviour including small strain non-linearity and anisotropic stress-strain-strength. The analyses consider the undrained deformations around a braced diaphragm wall in a soft clay deposit. Principal parameters considered in the study are the wall embedment depth and support spacing. A simplified framework is developed to interpret wall deflections and ground movements with excavation depth. (A) For the covering abstract see IRRD 860485.

Soil interaction effects on sloshing response of the elevated tanks

Abstract: The aim of this paper is to investigate how the soil-structure interaction affects sloshing response of the elevated tanks. For this purpose, the elevated tanks with two different types of supporting systems which are built on six different soil profiles are analyzed for both embedded and surface foundation cases. Thus, considering these six different profiles described in well-known earthquake codes as supporting medium, a series of transient analysis have been performed to assess the effect of both fluid sloshing and soil-structure interaction (SSI). Fluid-Elevated Tank-Soil/Foundation systems are modeled with the finite element (FE) technique. In these models fluid-structure interaction is taken into account by implementing Lagrangian fluid FE approximation into the general purpose structural analysis computer code ANSYS. A 3-D FE model with viscous boundary is used in the analyses of elevated tanks-soil/foundation interaction. Formed models are analyzed for embedment and no embedment cases. Finally results from analyses showed that the soil-structure interaction and the structural properties of supporting system for the elevated tanks affected the sloshing response of the fluid inside the vessel.

Shear behavior of horizontal joints between precast panels

Abstract: The objective of this study is to investigate the shear resisting capacity of precast wall-to-wall horizontal connection system by dowel action and shear friction. Three types of connection systems, which have varying embedment length in the upper wall panels, were investigated. The specimens were subjected to displacement-controlled lateral loading. The parameters investigated were the load–deformation relationship, ultimate load carrying capacity, ductility and energy dissipation. The experimental values were compared with the theoretical values of ultimate shear resisting capacity calculated from the Von Mises yield criteria, ductile bending failure due to the formation of plastic hinges and the shear friction hypothesis.