The civil engineering facilities at the University of Colorado at Boulder are well established, and include state-of-the-art software and computing centers as well as instructional- and research-oriented laboratories. General computer access is available through the Computer Aided Design (CAD) laboratory, the Bechtel Laboratory, as well as the M.Y. Leung Computational Laboratory. The CAD laboratory consists of 40 networked state-of-the-art PCs for undergraduate and graduate instruction. The Bechtel and Leung laboratories contain both advanced PCs as well as a network of high-performance Sun workstations with a central server and advanced graphics capabilities. Advanced engineering software available for geotechnical-related projects such as Abaqus, GeoStudio 2007 (Temp/W, SEEP/W, VADOSE/W, etc.), Plaxis, FEAP, SAP, among other software developed at the university. Graduate level research in analytical and computational modeling in geotechnical engineering is conducted in the M.Y. Leung Computational Laboratory for Soils and Structures.
The Geotechnical Engineering and Geomechanics facility at the University of Colorado Boulder consists of several laboratories used for instructional purposes, characterization of the fundamental mechanical, hydraulic, and thermal properties of soils on an element scale, and centrifuge-scale modeling of the performance of geotechnical systems (slopes, retaining walls, foundations, levees, dams, etc.).
The instructional geotechnical laboratory is used to conduct instructional sessions that are part of the coursework for undergraduate classes. The lab consists of five triaxial cell setups which can also be used for conventional triaxial tests (CU, CD, UU) as well as consolidation tests, a direct shear apparatus, constant head and falling head permeability setups, and a mechanical sieve shaker. Equipment is also available for standard soil classification tests.
The advanced geotechnical and geomechanics (graduate) laboratory includes a cluster of advanced testing equipment suitable for characterization of the element-scale properties of soils and geosynthetic reinforcements under static, cyclic, and dynamic loading. The laboratory includes 6 cubical cells of different sizes and load capacities which can be used to control the complete principal stress state in cubical soil, rock, or concrete specimens, with proportional or non-proportional loading under static or cyclic conditions. The largest cubical cell (18 cm side length) has been adapted to evaluate thermally induced water flow and volume change in unsaturated soils under different states of stress. The laboratory also includes specialized devices to characterize the thermal properties of soils, concrete, and rock, including an oedometer with temperature control to measure thermal-induced consolidation of soils, a triaxial cell incorporating a thermal-needle to measure thermal conductivity as a function of void ratio, and a 3 Hoek cells for rock characterization constructed from high strength aluminum which can be placed within an environmental chamber. The laboratory also contains a large-scale directional shear apparatus for evaluating anisotropy effects on soil strength, equipment designed for triaxial testing at low confining pressures, a cyclic triaxial cell with local strain measurement capabilities, two resonant column devices with flow pump suction-saturation control for small-strain shear modulus measurement for unsaturated soils, and bender elements for shear-wave velocity measurement.
A state-of-the-art flow processes laboratory is equipped with custom-made testing equipment used for studying flow phenomena in soils. Three flow pumps for precisely controlling flow rates are connected to modified triaxial cells in which various tests with saturated, unsaturated, and multiphase flow are performed. Typical tests performed in this laboratory include hydraulic conductivity of saturated and unsaturated soils, seepage-induced consolidation of soft soils, and multi-phase flow experiments. This laboratory is also equipped with conventional unsaturated soils testing equipment for determination of the soil water retention curve (rigid and flexible wall pressure chamber outflow devices and hanging column devices).
The University of Colorado Boulder’s Geotechnical Engineering and Geomechanics facility includes three state of the art centrifuges used for research, industry design, and instructional purposes. The largest of these centrifuges is a 400 g-ton Wyle centrifuge. In terms of g-ton capacity, this centrifuge is one of the most powerful in the world. It is capable of accelerating an 1815 kg payload to a maximum of 200 g in 14 minutes. The centrifuge is used for numerous research projects investigating the static and seismic performance of retaining structures and slopes, seepage mechanisms, contaminant transport, and offshore foundation structures. The 6 m radius of the centrifuge arm permits an essentially uniform g-level to be applied to the full height of the centrifuge model. The swinging-basket type centrifuge platform can support a container footprint of 1.2 m by 1.2 m. This platform can accommodate payloads with a height of 0.91 m, with a maximum headroom of 1.35 m for offset actuators and loading devices. One of the payloads is a loading frame which can be used to evaluate soil-foundation interaction. The centrifuge can be used to simulate earthquake motions in flight by utilizing a servo-hydraulic shake-table. The data acquisition system for the 400 g-ton centrifuge includes a NI PXI data acquisition system combined with a 12-slot SCXI chassis, with modules suitable for signal conditioning for LVDTs, strain-gauge-type sensors, accelerometers, and capacitance-type differential pressure transducers. Voltage control capabilities are also possible to operate solenoid and electronic flow valves. The 400 g-ton centrifuge includes 2 hydraulic rotary union lines which can be used to supply pressurized fluid to the centrifuge platform.
The second centrifuge is a 15 g-ton Genisco model 1230 centrifuge, which has a symmetrical arm comprised of aluminum sections carrying swing-baskets at each end. The 15 g-ton centrifuge accommodates experimental payloads up to 0.45 x 0.42 x 0.60 m and will accelerate a payload of 140 kg up to 200 g. This centrifuge has been converted for use as a centrifuge permeameter to investigate infiltration and drainage flow processes in unsaturated soils.
The third centrifuge is the instructional geotechnical centrifuge. Although this centrifuge has been in operation since 1996, it was completely refurbished using a grant from NSF during the summer of 2004 to accommodate symmetrical swinging baskets, video data acquisition system, and a high performance AC drive motor. This centrifuge is primarily used as an instructional tool in undergraduate geotechnical engineering labs to introduce simple concepts of slope stability, active and passive earth pressure conditions, and bearing capacity taught in undergraduate classes.
Specialized equipment in the Geotechnical Engineering and Geomechanics laboratories include: