14 publications from this institution
A numerical model, called CS3, is presented for one-dimensional, large strain consolidation of layered soils. The algorithm accounts for vertical strain, soil self-weight, conventional constitutive relationships, changing material properties during consolidation, unload/reload, time-dependent loading and boundary conditions, an externally applied hydraulic gradient, and multiple soil layers with different material properties. CS3 can accommodate equilibrium and nonequilibrium profiles for the initial void ratio as well as variable profiles for preconsolidation stress and applied stress increment. Verification checks show excellent agreement with available analytical and numerical solutions. Several numeric examples are used to illustrate the capabilities of CS3 and highlight errors that may occur when multilayer systems are modeled as a single layer with average properties. Finally, settlement estimates obtained using CS3 are in good agreement with field measurements for the Gloucester test fill.
This paper presents the results of field performance tests of 39 in-service corrugated steel highway culverts in Ohio. The culverts had span lengths varying from 3.23m(10.6ft)to7.04m(23.1ft) and backfill soil heights over the crown varying from 0.27m(0.9ft)to7.47m(24.5ft). Static and dynamic load tests were conducted by driving heavy trucks across the culverts. Static loads were applied at ten different locations above each culvert. Dynamic load tests were conducted at six truck speeds varying from 8km∕h(5mi∕h)to64km∕h(40mi∕h). A portable instrumentation frame was installed inside each test culvert to monitor deflections. Strains on the culvert walls were also measured at 14 locations using strain gauges. Effects of backfill height and loading conditions are investigated. According to the experimental results, a plot of maximum culvert deflection versus backfill height shows a nonlinear relationship. Maximum static load deflections were found to be consistently larger than the maximum dynamic deflections obtained using the same test truck. Deflections were nearly zero for deep culverts with backfill heights exceeding 4m(13ft). Maximum deflections correlate more closely to equivalent line loads than to total truck weight. The data also indicate that culvert behavior is more difficult to predict when backfill heights are shallow because other factors, such as culvert age and condition and soil type, likely play a significant role.
