At Sites 607 through 611, drilling on Leg 94 with the Hydraulic Piston Corer retrieved cores in upper sediment layers with large-scale CaCO 3 variations related to Pleistocene and late Pliocene glaciations over the last 2.5 m.y. The visually striking color-layering caused by these variations permitted detailed correlations between holes on a scale not possible with shipboard paleomagnetics and biostratigraphy. These correlations indicate that demonstrably continuous sections extending back to at least 2 Ma were retrieved at Sites 607 to 610. There appears to be a gap in record continuity at Site 611 in the upper Pleistocene. Making these correlations on site during Leg 94 enabled us to recore intervals where loss of continuity was known or suspected.

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This paper presents a case study of a residential house damaged by expansive soils. The field investigation revealed that the damage was most likely caused by excessive lawn watering and leaks of sewer pipe and/or stormwater pipe, which resulted in non-uniform soil moisture conditions. Three-dimensional back analysis of this distressed structure indicated that stresses were most critical at a re-entrant corner and that steel reinforcing bars in the beam in this area had yielded. The results of the back analysis also indicated that a stronger footing was required to limit differential deflection to an acceptable level and reduce stress in the footing.The case study has clearly shown that a leaking underground water pipe and/or excessive watering of a garden could cause more severe distortion to a single storey masonry veneer house than could be expected from seasonal moisture change and the deeper moisture redistribution caused by the imposition of the house on seasonally dry reactive soil. Moreover it has been demonstrated that it would be extremely costly to design a footing for extreme, or abnormal, moisture changes.

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This paper presents experimental results on the effect of matric suction on the resilient modulus of four recycled unbound granular materials. The recycled materials were prepared at moisture contents ranging between 70% and 90% of optimum moisture content (OMC) and tested in a repeated load triaxial test (RLTT) apparatus under various stress regimes. Soil-water characteristic curves (SWCC) were established for each material by preparing samples at various moisture contents and measuring matric suction with filter papers. To obtain the wet end of the SWCC, further samples were conditioned on a tension plate at suctions controlled by the hanging water column method. Some published models for prediction of resilient modulus were applied to the experimental data, but the correlations were unsatisfactory generally, and so an improved model was sought. Subsequently, a model with four terms and six constants was developed, which followed the general power law. A single set of material constants was found for all recycled materials to provide satisfactory predictions of resilient modulus (R2 = 0.88), over a wide range of stresses and moisture states.