Editor: Chris Ramseyer

With the exception of #9, these Papers were presented at: ACI National Convention, Fall 2012 Toronto, Canada. In the Technical Session Shrinkage Compensating Concrete – Past, Present, and Future Part 1 and Part 2.

This publication is dedicated to Edward K. Rice

Ed Rice has been involved in Shrinkage Compensating Concrete from its inception. As co-founder and President of T.Y. Lin and Associates from 1952 through 1970 Ed Rice promoted the novel use of concrete and concrete systems. As early as 1956 T.Y. Lin and Ed Rice provided the necessary funding for fundamental research by Alex Klein on expansive cements. This research led to the development of the Chemically Prestressed Concrete (CPC) co that was primarily in the pipe and roof slab business. In 1965 under Ed Rice’s direction as Chairman of CPC, Ed licensed Kaiser to run the first full scale burn at their Cushenberry cement plant and commercially produce the first shrinkage compensating concrete clinker in the world.

In the fifty years since the first production run of shrinkage compensating cement Ed Rice has consistently worked to advance concrete cement technology. He holds 22 US patents in the field of concrete and building technology. For the last forty years Ed Rice has led CTS Cement Manufacturing Co., the largest producer of shrinkage compensating cement in North America. Often Ed Rice worked behind the scenes helping to promote shrinkage compensating concrete and the work of younger engineers. Ed Rice has been a consistent and steady advocate for both increased research on the behavior of shrinkage compensating cements; and increased use of shrinkage compensating concrete to produce stable and durable concrete structures.

Note: The individual papers are also available. Please click on the following link to view the papers available, or call 248.848.3800 to order. SP-307

In the modern transportation industry, nearly all bridge decks are constructed of concrete. Of the concrete bridge decks currently in service across the US, almost all contain large numbers of cracks. These cracks are the bane of deck longevity. They allow the ingress of salts that cause corrosion of the reinforcing steel, exacerbating concrete cracking and loss of structural capacity. A survey conducted several years ago by Folliard et al. (2004) for the FHWA found that more than 100,000 bridges suffered from early-age cracking. This paper presents a case study of bridge decks in Ohio and Michigan that are essentially crack-free. Some of these bridge decks are located on high volume highways/interstates and are up to 30 years of age. In addition, several of these bridges have adjacent standard Portland cement concrete sister bridges built at the same time, with identical spans and construction details handling traffic flowing in the opposite direction. Comparison of these bridges offers unique insight into a simple, effective solution for mitigation of bridge deck cracking.

Samples of Type K shrinkage-compensating cement from all 17 mills producing that cement in 1974 were obtained and evaluated for compliance with the specification that was proposed at that time for these types of cements. The cements were also evaluated for specific gravity, fineness, heat of hydration, and expansion and drying shrinkage in mortars. An X-ray diffraction analysis was also made for each cement in an attempt to compare cements to note significant differences in composition or relative amounts of constituents. A standard concrete mixture was also made with all the cements and evaluated for air content, slump, compressive strength, expansion, and drying shrinkage. The results from these evaluations are revisited. The application of the 1974 proposed specification called attention to several short-comings in that specification.

In order to be cost-effective, surface repairs carried out on concrete structures have to perform satisfactorily over a sufficient period of time. Among the factors that can affect the durability of concrete repairs, drying shrinkage is certainly one of the most significant. Shrinkage compensating concretes (ShCC’s) represent a very attractive alternative to prevent shrinkage cracking in repairs. This paper summarizes the results of a project devoted to repair ShCC’s made with an expansive component, more specifically their robustness as a function of selected parameters. The investigated expansive systems were either, a calcium sulfoaluminate-based (ASTM Type K cement or Type K component) or calcium oxide-based (ASTM Type G component). The assessment of robustness addressed the influence of the mixture design parameters (cement composition, type and dosage of expansive agent, w/cm ratio) and the curing conditions (moist curing conditions, temperature) upon the ShCC’s expansive behavior, the bond between ShCC repairs and an existing concrete substrate, and the chemical prestress generated through the bond. Overall, the results yielded in this study demonstrate the remarkable potential of ShCC’s as crack-resistant and durable repair materials.

Expansive component systems provide the possibility to control the effects of concrete drying shrinkage in civil engineering applications, promoting durability for new construction and repair alternatives. Drying shrinkage is a natural consequence of concrete upon water loss after hardening. When there are restrictions such as internal reinforcement, adjacent structural elements and subgrade friction, concrete drying shrinkage can lead to cracking if no provisions are considered on the mix design or on the construction procedure. Expansive component Type G reacts chemically with Portland cement and water in the concrete mix to produce calcium hydroxide platelet crystals, which after setting, produce a volume increase. Providing internal or external restrictions, a concrete, that contains an expansive component system, can induce compression stress in the concrete mass and tension stress in the reinforcement. Concrete cracking can be reduced because such induced compression stress counteracts the tensile stress in the concrete mass caused by drying shrinkage. This article comprises a variety of applications of concrete, including the expansive component Type G, in Mexico as a solution means of improved functionality and durability of modern construction.