This Major Research Instrumentation grant is for the acquisition of a 500 kN (110,000 lbs.) capacity servo-hydraulic tension/compression test machine with the ability to apply cyclic loading. The test machine will have a cross-head mounted actuator for maximum flexibility in the types of samples which can be tested. The open space between the load cell and the base is three meters, allowing for testing of long specimens. In addition to inputs for the load and stroke, there are additional channels with two universal conditioners and six channels of preconditioned (DC) input; all channels can be used as feedback control or even a combination of signals. The primary uses for the test machine will be for senior projects and research for Master's theses. The PIs have specific ongoing or proposed research in the following areas in which the intellectual merit of the work would benefit by the unique capabilities of the new test machine: (1) effect of failure localization on compressive stress-strain behavior of concrete, (2) quantification of the initiation and growth of cracks in reinforced concrete members (3) determination of the resilient modulus of paving materials, (4) fatigue and strength testing of mechanical joints, and (5) compression tests of filament wound composite tube struts. The test machine being acquired fills a gap in the testing ability for the entire College of Engineering at the California Polytechnic State University at San Luis Obispo. The PI and co-PIs represent three different Departments within the College of Engineering. Civil and Environmental Engineering already has test machines with greater and lesser load capacity; however, none of the test machines have the ability to apply cyclic loads or control brittle fracture of specimens using feedback signals. Aerospace and Mechanical Engineering Departments both have servo-hydraulic test machines with cyclic tension/compression abilities and closed-loop feedback control; however, the largest capacity machine in each department is 100 kN (22,000 lbs.). The proposed test machine will also have greater clear space between loading surfaces than any of the current testing facilities. The students and the local community will both be beneficiaries of the broader impact of acquiring the test machine. Cal Poly has one of the largest non-PhD granting engineering colleges in the country with undergraduate enrollments exceeding 4500 and a growing master's program. Coupling Cal Poly's requirement that every student must complete a senior project and its "hands-on" philosophy, the new instrument will be a valuable asset in helping numerous students understand what state-of-the-art test equipment is capable of and helping them better understand the mechanical behavior of materials. Furthermore, much of the research conducted at Cal Poly is of a practical nature, serving the needs of industry and public agencies within the state. Attracting funding also helps the local community which is isolated from major metropolitan areas and has little industry other than the University. The test machine will be located in the new Paving Materials and Advanced CE Materials Lab. This laboratory will be operated under the joint supervision of the PI and one of the co-PIs. This laboratory is housed in Building 13 on the Cal Poly campus. Building 13 is the primary location for the Civil, Mechanical, and Aerospace Engineering Departments; their Department offices, laboratories, and faculty are mostly contained within this building providing easy access to the equipment. The PI has extensive research experience with closed-loop testing at other institutions; he has developed unique closed-loop test techniques which allow for measurements which would not otherwise be obtainable. The PI will be the primary operator and will provide training to those using the equipment so the full capabilities of the machine will be utilized. The Civil and Environmental Engineering Department will the responsible party for regular maintenance and calibration of the test machine.
