SUMMARYEvidence for threshold gradients is reviewed. The consolidation problem, with threshold gradient, is properly formulated and solved numerically. An approximate analytical solution is also developed. The influence of a threshold gradient on the time rate of settlement is examined, and it is shown that by modifying the definition of the degree of consolidation a good approximation to the threshold gradient problem can be obtained directly from the Terzaghi solution. It is also shown that threshold gradients will have no influence on odometer testing and their effect is, therefore, to reduce the primary compression below that predicted from standard tests.
A 2-D numerical finite-difference model has been developed t o calculate t h e thermal conductivity of a composite material. T h e method is general in that t h e distribution of components within the material can be ordered or random. Results from the calculations are compared with those based o n a geometric model in which the conductivity of the composite depends o n the volume fractions of t h e different components and with conductivities calculated using real-space renormalization group theory (RSRG) and t h e effective medium approximation (EMA). The results from t h e present work compare well with the geometric model and the EMA, whereas the RSRG results generally indicate lower conductivities. Possible reasons for the differences between the RSRG theory and t h e other methods are discussed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.