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The Indiana Department of Transportation (INDOT) constructed four bridge decks utilizing internally cured, high performance concrete (IC HPC) during the summer of 2013. These decks implement research findings from the research presented in the FHWA/IN/JTRP‐2010/10 report where internal curing was proposed as one method to reduce the potential for shrinkage cracking, leading to improved durability. The objective of this research was to document the construction of the four IC HPC bridge decks that were constructed in Indiana during 2013 and quantify the properties and performance of these decks. This report contains documentation of the production and construction of IC HPC concrete for the four bridge decks in this study. In addition, samples of the IC HPC used in construction were compared with a reference high performance concrete (HPC) which did not utilize internal curing. These samples were transported to the laboratory where the mechanical properties, resistance to chloride migration, and potential for shrinkage and cracking was assessed. Using experimental results and mixture proportions, the diffusion based service life of the bridge decks was able to be estimated. Collectively, the results indicate that the IC HPC mixtures that were produced as a part of this study exhibit the potential to more than triple the service life of the typical bridge deck in Indiana while reducing the early age autogenous shrinkage by more than 80% compared to non‐internally cured concretes.

Internally cured (IC) concrete is frequently produced in North America using pre-wetted lightweight aggregate (LWA). One important aspect associated with the production of quality IC concrete is the accurate determination of the moisture content, including absorbed moisture and surface moisture of the LWA. Knowledge of the moisture content enables aggregate moisture corrections to be made for the concrete mixture, thereby enabling an accurate water-to-cement ratio to be maintained. Two methods for determining the moisture content of LWA include the specified ASTM C1761-13b “paper towel method” and a method that uses a centrifuge (Miller, Barrett, Zander, & Weiss, 2014). There are limited data available on the variability associated with either of these approaches when the test is performed by multiple users. In this study, the absorption of four commercially available LWAs was tested by a single operator in a single laboratory using the centrifuge method. In addition, the absorption of three commercially available LWAs was tested by 25 users performing both experimental methods. This article provides an estimation of precision associated with both a single operator and multiple operators performing both the paper towel method and the centrifuge method to find the absorption of pre-wetted lightweight fine aggregate.

Internally cured (IC) concrete is frequently produced using pre-wetted lightweight aggregate (LWA). One important aspect associated with preparing quality IC concrete is being able to determine the absorbed moisture and surface moisture associated with the LWA which enables aggregate moisture corrections to be made for the concrete mixture. ASTM 1761-13b specifies the use of the “paper towel method” to define a surface dry state for pre-wetted LWA; however, this can be time consuming and hard to perform at the batching plant. This paper proposes an alternative method for obtaining a surface dry state of the aggregate based on spinning the pre-wetted LWA in a centrifuge. It is shown that using a centrifuge (with bowl radius of 11.4 cm) for 3 min at 2000 rpm permits a surface dry state to be obtained consistently which enables surface and absorbed moisture to be determined accurately and rapidly. The moisture values obtained using the centrifuge correspond well with those obtained using the paper towel method.

The magnetic anisotropy and magnetostriction of single crystals and the magnetostriction of some polycrystalline specimens of several Fe rich Fe-Co- Al alloys has been experimentally determined. Specialized apparatus and procedures for alloy preparation, single crystal growth, crystal cutting, crystal orientation, magnetization and magnetostriction studies have been developed.

The lowest form of life is a cell, which is defined as a minute mass of protoplasm. Each individual cell is of sufficient importance to have a life history of its own. It has its origin from some pre-existing parent cell, grows, fulfils its mission, produces other cells, wastes away and dies. All action is attended with waste. There must be food supplied in proportion to this waste or existence would cease. If the supply is less than the waste existence may be prolonged but must finally terminate. If the food supply equals the waste, there will be no apparent change. If it exceed the waste, there will be increase in growth. To keep an animal in a perfect condition the quality and quantity of food should be such as will best supply the place of that which is worn out. In the development of the infant after birth nature