Of the 18 papers included in this volume, 9 were presented at the 75th Annual Meeting of the Transportation Research Board in four different sessions. The remaining nine papers were presented at the meetings of the respective sponsoring committees. The first nine papers provide information to practitioners and researchers interested in resilient modulus testing and evaluation of stabilized materials. The first four papers in this group were included in the session titled Resilient Modulus Testing of Stabilized Materials, organized by Roger K. Seals, Louisiana State University. Ping and Ge present the results of laboratory resilient modulus measurements on several cemented lime rock materials from in-service pavements in Florida and compare them with elastic moduli backcalculated from field plate bearing load tests. Little discusses the findings of Texas Department of Transportation research on lime-stabilized subgrades, indicating that on the basis of falling weight deflectometer and dynamic cone penetrometer results, they provide stiffness and strength characteristics similar to unbound aggregate base. Puppala et al. report on their investigation of resilient and strength behavior of lime-treated subgrade soil by resilient modulus, unconfined compression, and California bearing ratio tests, which lead to a regression model. The effectiveness of emulsified bases is assessed by resilient modulus tests by Farrar and Ksaibati, who emphasize that aging the samples significantly affects the test results. Chang et al. discuss the applicability of various sludge stabilization and solidification methods that use portland cement, gypsum, and other agents. Senadheera et al. describe the properties and uses of hydrated fly ash as a flexible base material. Hydrated fly ash is formed by dumping high-calcium fly ash into curing ponds and milling or crushing it after hardening to produce granular material. Kota et al. address sulfate-induced heave problems related to calcium-based stabilizers. They discuss the benefits of double lime applications and other methods of remediation. The next two papers were presented at the session titled Flowable Fills, organized by C. W. Lovell, Purdue University. Bhat and Lovell discuss the mix design considerations and testing of foundry sand, cement, and fly ash mixtures. Gandham et al. present results of their research on the technical and environmental feasibility of using phosphogypsum and high-calcium fly ash as a flowable fill. Load and resistance factor design (LRFD) has been used in the United States for bridge superstructure design, whereas the application of the approach for pier and abutment design is new and ensures integration in the design of the various structure components. Two papers included in this volume were presented at a session titled Load and Resistance Factor Design, organized by James L. Withiam, D’Appolonia. Goble illustrates and compares the design of a pile-supported structure using LRFD and AASHTO working stress design specifications. Phoon and Kulhawy discuss the development of reliability-based design criteria, which emphasize the importance of reliability assessment techniques and the compilation of geotechnical variabilities in determining the probability of failure and the target reliability level. Norris et al. discuss the behavior of the California Strong Motion Instrumentation Program instrumented wharf at Oakland Outer Harbor during the 1989 Loma Prieta earthquake. Chen and Kim describe a nondestructive test based on the dispersive wave propagation technique for assessing the in situ condition of timber piles. The paper by Ostendorf et al. was presented at the session titled Remediation of Contaminated Highway Rights-of-Way, organized by Steven M. Huddleson, Camp Dresser and McKee, Inc. Ostendorf et al. report their findings from a study of bacterial degradation of petroleum-contaminated soil in the highway right-of-way in Massachusetts. Khedr and Ahmed describe a new process of chemical grouting that reduces permeability of the treated material and eliminates the risk of environmental contamination. The last three papers discuss the effects of environment on pavement systems. Khogali and Anderson describe subgrade resilient characteristics of Alberta pavement layers by coupling falling weight deflectometer test results with those of temperature and moisture suction measurements. Eigenbrod and Kennepohl report the results of laboratory tests and field measurements of temperature conditions of ground below pavements leading to water accumulations that could cause premature failures. Clarke and Nevels present information on the relationship of drying shrinkage and moisture with suction in an alluvial clay deposit. (Author/publisher)
Samenvatting