When soil is compacted in layers by rollers, vibrating plates, or rammers, the horizontal earth pressures within the compacted soil mass are increased. Charts are presented that can be used to estimate compaction‐induced earth pressures quickly and reliably. These charts are developed using the hysteretic theory developed by Duncan and Seed, with a computer program called EPCOMP2. The charts offer the advantages of being easy to use, and providing very rapid results, while retaining most of the accuracy of the detailed computer analyses. Because earth pressures can be estimated quickly, it is easy to evaluate the effects of changes in the factors that influence the magnitudes of the compaction‐induced earth pressures. Comparisons of earth pressures calculated using these charts with the results of computer analyses indicate that the values calculated using the charts are sufficiently accurate for practical purposes. Field measurements of compaction‐induced earth pressures indicate that the horizontal earth pressures induced by compaction of sand do not change appreciably with time unless the wall on which they act moves toward or away from the backfill. In clay backfills, the high horizontal pressures induced by compaction tend to decrease over time to normal at‐rest values.

The device allows controlled transfer of the building loads to the foundation piles, such that the building neither settles nor emerges with respect to the surrounding ground, in areas where the subsoil is highly compressible, as is that of Mexico City. Additionally, the device dissipates energy when the building experiences rocking motion under the action of earthquake forces. The device is fixed to the head of each of the foundation piles, which pass freely through the building base slab. Also, the device is fixed to the base slab, such that it provides, by means of deformable elements that undergo a rolling‐bending motion, a variable length connection between foundation piles and building.

Results of a numerical study are presented on the kinematic response of groups of vertical floating piles connected through rigid massless caps and subjected to vertically propagating harmonic S‐waves. Pile‐soil and pile‐pile interaction effects are modeled rigorously. Parametric results for the “effective seismic pile‐cap motion,” normalized by the “free‐field” ground‐surface motion, are displayed in dimensionless form for a number of typical pile‐group configurations, in three idealized soil profiles: a homogeneous half‐space, a half‐space with modulus proportional to depth, and a two‐layered stratum. It is shown that, whereas the influence of the nature of the soil profile is profound at all frequencies, the effects of pile‐group configuration, number of piles in the group, and relative spacing between piles are usually insignificant for lateral displacements, but quite important for pile‐cap rotations. Pile‐head “fixity” conditions and the pile/soil modulus ratio are found to affect appreciably and in a similar way the seismic response of a single pile and of a pile group.

The ground behavior near circular tunnels in cohensionless soils, including the initial elastic response, the intermediate yielding, and the ultimate collapse, is explored in detail. Different modes of tunnel behavior are identified and the conditions for their occurrence are estimated using analytical solutions. The results compare well with those from finite‐element analyses, model tests, and field measurements. The ground convergence curve concept is applied as an analytical tool to interpret the response of the ground to tunneling. It is demonstrated that this method quantitatively relates the development of pressure on the lining to the tunnel wall displacement for the entire spectrum of the ground behavior, and thus provides an optimum design tool for lining pressure or ground‐displacement control. The validity and limitations of currently available lining design models are also addressed.

A new, simple, semi‐analytic technique for modeling contaminant migration through an unfractured clayey liner underlain by fractured soil (or rock) and an aquifer is described. The model is implemented on a microcomputer and allows consideration of advective‐diffusive‐dispersive transport through the liner (including sorption, where appropriate), advective‐dispersive transport through the fractures, matrix diffusion from the fractures into the adjacent soil, sorption on the fracture surface and in the soil matrix, and finite mass of contaminant in the landfill and dilution in the aquifer. The application of the model is illustrated by considering migration from a hypothetical landfill separated from an underlying aquifer by fractured till. Consideration is given to impact without a liner and with a reworked till as a compacted clay liner underlain by fractured till. The results obtained by modeling migration through the compacted liner and fractured till are compared with what would be obtained using approximate approaches that consider either the liner alone or consider the full thickness to be fractured.

Prediction of load‐carrying capacity of piles in cohesionless soils has been and is still one of the most challenging problems facing geotechnical engineers. The problem is complex and difficult due to the lack of understanding of the phenomena of soil‐pile interaction, and the limited quantity and inexact quality of subsurface soil information that can be provided for analysis. Current methods of estimating pile capacity have uncertainties that are not accounted for, including uncertainties in the method and in the data used to execute the method. Many of these uncertainties defy conventional quantification. The application of fuzzy‐set theory, which can assist in accounting for these uncertainties, is offered as a solution. A model based on the theory of fuzzy sets that estimates ultimate capacity of single piles in sand is presented. Uncertainties associated with both input data and predicting methods are accounted for. In particular, qualitative information and subjective judgment are incorporated in the computations. A computer program that adopts the proposed model yields improved prediction of ultimate capacity for the cases studied.

The fabric of a medium plastic clay soil has been characterized by the distribution of the sizes of the void spaces in the soil. The soil has been compacted in the field by static—and vibratory—segmented pad rollers with different energies and water contents. Laboratory compaction by impact and kneading procedures was also conducted with different energies and water contents. Pore-size distribution was determined by mercury-intrusion porosimetry for each of the various as-compacted conditions created. Differences in the distributions were said to infer differences in soil fabric. Different energy levels created different fabric at comparable water contents relative to optimum. Only on the wet side of optimum for standard proctor energy could the fabric of laboratory and field compaction be labelled similar. It was concluded that for all other conditions the fabric of field compacted soil should be considered different from that produced by laboratory compaction. No laboratory procedure appears capable of always reproducing the fabric of field-compacted soil. Thus, there appears to be no substitute, today, for testing the field-compacted soil when behavior parameters are being determined.

Many soft-clay deposits are overlain by a stiffer layer or crust. The stiff upper layer spreads the applied loads over a wide surface of the soft soil providing an effect similar to surcharge stress. The bearing capacity of the lower soft soil is estimated considering the load spread outside the footing width as a variable surcharge stress. Linear and exponential decreases and a triangular distribution of stresses are analyzed. The improvement in bearing capacity is obtained as a function of the extent and distribution of the surcharge stresses.

The mechanism and causes of the initial rotation error encountered in portable borehole deflectometers are described. The error is viewed as a systematic propagation of any discrepancy that affects the precise correlating of movements to the reference of measurement. A simple method, called reverse analysis, is proposed that helps rectify the measured movement profiles.