Abstract: Results of small-scale laboratory model tests to determine the ultimate bearing capacity of a strip foundation supported by sand with multiple layers of geogrid reinforcement are presented. Tests were conducted with only one type of geogrid and a sand compacted to one relative density. The embedment ratio of the foundation was varied from zero to 0.6. It is found that, for the given reinforcement-depth ratio, the bearing capacity ratio with respect to ultimate load increases with embedment. The relationship between the bearing capacity ratio at ultimate load and at limited levels of settlement (less than or equal to 5% of foundation width) is also presented. The bearing capacity ratio at limited levels of settlement is smaller than the value at ultimate load.

Abstract: Technical Engineering and Design Guides, as adapted from the U.S. Army Corps of Engineers, No. 15 From foundation exploration and testing procedures to analysis techniques and allowable criteria, this comprehensive guide provides information on the selection, design, and installation of sheet pile walls based upon the current state of the technology for sheet pile–soil–structure interaction behavior. Topics include: open channel hydraulic theory; system loads including surcharge and water loads; system stability and design for rotational stability; nonlinear soil springs; nonlinear anchor springs; corrosion; liquefaction potential during driving; and settlement.

Abstract: The dynamic response of Morrow Point Dam to Taft ground motion is presented for a wide range of properties of the dam, foundation rock, impounded water, and reservoir boundary materials. Based on t...

Abstract: General means for evaluating the vibration behaviour of turbogenerator installations where the foundation has natural frequencies in the operating range have not been satisfactorily developed because one does not normally have access to an accurate foundation model and modal testing of the foundation is suspect owing to the already installed rotor. Hence, various techniques have been proposed to devise equivalent foundations which produce the same system dynamic response over the speed range of interest. The approach in this paper is to represent foundations in terms of their modal parameters. The unbalance responses are evaluated at selected speeds. By minimising an objective function derived from these responses, the foundation is approximated via modal parameters to give a so-called equivalent foundation, the adequacy of which is tested by comparing the vibration behaviour of the actual system with that using the simplified foundation. Provided measurement accuracy to three significant digits can be achieved, natural frequency and unbalance response comparisons showed good agreement.

Abstract: A procedure is presented for the analysis of the stability and propagation of cracks in arch dams based on linear elastic fracture mechanics and three-dimensional boundary element modeling. A simplified crack propagation criterion is employed and the crack trajectories are obtained by multistep extension. The first upstream cracking which occurred in the Kolnbrein arch dam is studied in detail under various conditions concerning the foundation interface, location of crack initiation, reservoir water level and load combinations. Crack trajectories close to the observed one are obtained with water level at 1,850–1,860 m, which agrees with the prototype experience. It is found that the hydrostatic load and associated uplift pressure on the crack surfaces are the key factors for causing an initial crack at the dam base to propagate to the upstream face. It is also noted that the bonded condition at the interface between the dam and the upstream elevated foundation is responsible for producing the distinctive ...

Abstract: A simplified ground heat loss calculation method for slab-on-grade floors and basements is developed. The method is based on the results from the ITPE method and is suitable for seasonal heat loss calculation. The simplified method consists of a set of equations for estimating the monthly total heat flow between a building and the ground as a function of a wide range of variables such as building dimensions, insulation configurations, and soil thermal properties. The equations are designed to accept continuously variable input values. The simplified method predictions are tested against Mitalas`s and ITPE results. The agreement between the correlations and the ITPE method is found to be within 10% for the annual mean, amplitude, and phase angle of total building heat loss.

Abstract: Laboratory model test results are presented for the cyclic load-induced settlement of a strip foundation supported by a saturated clayey soil. In performing the tests, the foundation was initially subjected to an allowable static load, after which a cyclic load with a frequency of one cycle per second was superimposed on it. The magnitudes of the static load and the amplitude of the cyclic load were varied. Based on the model test results, relationships for the foundation settlement and intensities of the static and cyclic loads are presented.

Abstract: A system and method for preventing the accumulation of water below and about a building and soil surrounding the building, the building having a foundation built on disturbed soil, which is in turn surrounded by undisturbed soil and the foundation extending to a depth. The system includes at least one trench section about the foundation, the trench being at least as deep as the disturbed soil about foundation and having sides and a bottom. At least one side of the trench being bounded by undisturbed soil. The trench section also includes a first end and a second end, the trench bottom having a slope between the first end and the second end, the second end terminating in a sump pit. An impermeable liner over the sides and bottom of the trench and extending into the sump pit. The impermeable liner is inserted into and held against the undisturbed soil that forms a side of the trench by a substantially rigid edging material, so that water filtering through the disturbed soil about the building foundation will reach undisturbed soil and flow over the undisturbed soil, where it will flow over the rigid edging material and into the lined trench, and then into the sump pit, so that water in the disturbed soil is collected in the sump pit before accumulating under and about the building foundation.

Abstract: In this paper, the seismic response analysis of concrete gravity dams is presented using the concept of Continuum Damage Mechanics. The analysis is performed using the finite element technique and a proper material degradation/damage model. The damage criterion used here is a second order tensor model based on elastic-brittle characterization and on a power function of the principal tensile stress. The methodology employed is shown to be computationally efficient and consistent in its treatment of both damage growth and propagation. Other important features considered in the analysis are: (1) dam-foundation interaction (2) appropriate modelling of joined rock mass using continuum damage mechanics, and (3) proper modelling of unbounded domain of foundation rock. The infinite media representation of the foundation material has been achieved by using doubly asymptotic approximation. The results of the analysis indicate that the seismic response of a damaged concrete dam could be significantly different from that of an undamaged one. In particular, the analysis shows that during a seismic event, the microstructure of a damaged zone can significantly change due to growth and propagation of microcracks.

Abstract: It is at least intuitively evident that variability in soil properties will have a significant effect on total and differential settlement of structural foundations. By modeling soils as spatially random media, whose properties follow certain distributions and spatial correlation structures, estimates of the reliability of foundations against serviceability limit state failure, in the form of excessive differential settlements, can in principle be made. The soil’s property of interest is it’s elastic modulus, , which is represented here using a lognormal marginal distribution and an isotropic correlation structure. Prediction of settlement below a foundation can then be made using the finite element method given a realization of the elastic modulus field underlying the foundation. By generating and analyzing multiple realizations, the statistics and density functions of total and differential settlements can be estimated. This paper estimates probabilistic measures of total settlement under a single spread footing and of differential settlement under a pair of spread footings using a twodimensional model combined with a Monte Carlo simulation. For the cases considered, total settlement is found to be well represented by a lognormal distribution and simple relationships are proposed allowing the approximation of the settlement distribution parameters for a footing founded on a spatially random soil of constant depth and fixed Poisson’s ratio. A one-parameter exponential distribution is fitted to differential settlements and found to give reasonable probability estimates, particularly towards the tail of the distribution. A method of predicting the single parameter is given in terms of statistics of the elastic modulus field and local averages over the field. An example is presented to illustrate the proposed methodology for a single footing.

Abstract: A thermal insulated concrete forming system for casting a concrete slab and a foundation wall of a building simultaneously is disclosed. The concrete forming system is designed for use with a pre-existing standard concrete footing that is constructed about the periphery of a concrete slab to be poured. The concrete forming system consists of a plurality of elongated, rectangular panels which are arranged in parallel, vertically opposed relation. The panels are fabricated from thermal-insulating materials having exceptional insulating characteristics capable of being expressed as a specific R value in accordance with commercial specifications. The thermal-insulated panels are interconnected by a plurality of brace members extending therebetween and being spaced at predetermined intervals so as to provide a form work for concrete to be cast therein. The thermal-insulated panels are assembled in a predetermined relationship to control the vertical elevation and thickness of a concrete slab and a foundation wall which are simultaneously cast therein the concrete forming system is disposed on a top surface of a standard concrete footing and remains in place to provide peripheral insulation of the slab and foundation wall to reduce the heating and cooling load on the building so constructed. The concrete forming system can be pre-assembled in accordance with appropriate dimensions in a workshop in preparation for pouring a concrete slab on a remote job site.

Abstract: A discussion of a paper with the aforementioned title by Hsu, Fu, and Schelling, published in this journal (Volume 121, Number 3, March 1995), is presented. Discussers Cortinez and Piovan report that the EBEF method for the distortional analysis of box girder bridges proposed by the authors is more versatile than the traditional beam on elastic foundation (BEF) analysis because it can be applied with great simplicity to more complex problems, such as varied sections and multispan beams. Cortinez and Piovan present an alternative finite-element (FE) formulation, based on exact solution, that is more convenient, for some situations, than the authors' approach. Discussion is followed by closure from the authors.

Abstract: This paper reviews the main issues to be addressed in the design of shallow and deep foundations which may be subject to earthquake loading. Information is presented on the soil properties required as well as the various design analysis techniques with a view to assessing the current state-of-the-art and highlighting areas in which further techniques need to be developed. The paper sets out, by way of an overview, a sequence of steps that a designer may follow in developing a foundation system. It is concluded that, at present, the greatest deficiencies lie in the areas of most potential use to designers. A secondary aim of the paper is to enhance communication between geotechnical and structural engineers on aseismic foundation design.

Abstract: This unavoidable disconnection between each chapter and the accompanying footnotes may be part of the reason why I have found this book uncomfortable to read. It is not that the topics are excessively technical or esoteric; they are not. Nor is it that frequent allusions are made to a wide range of ethicists whom I seldom read. Hauerwas in fact makes it easy to grasp the heart of what his authors say. It is rather that he is at home in a mixture of styles academic and popular, ecc1esial and political,literary and bordering on the vulgar, intellectual and homiletic that I would prefer to distinguish more carefully.

Abstract: The paper discusses the application of reliability theory to offshore foundation piles. The theoretical risk of failure for piles is computed for a range of realistic soil and loading conditions. The reliability analyses are updated in the light of long term field experience and the results used to comment on reassessment procedures for foundations. It is concluded that, if standard design procedures are followed, the outcome is likely to be that, generally, piles in sand are more at risk of failure than piles in clay, and piles governed by the dead load condition more at risk than those for which the extreme environmental load governs.