Category Archives: Concrete

What is Concrete and how is it placed?

Concrete is a mixture of two components: aggregates and paste. The aggregate component is normally composed of sand and gravel or crushed stone. The paste component is normally comprised of cement, water and admixtures.

Concrete is usually placed using either the form-and-pour or form-and-pump method. Both methods usually involve the design and construction of formwork around the repair section (or new construction application), in order to shape the final grade of the concrete section to be placed. Placing concrete into a horizontal concrete repair section would be the exception, wherein formwork is generally not required.

Indianapolis-Marion County Public Library, Indianapolis, IN

indianapolis-marion

The advent of personal computers, Internet access, e-books and other information technologies had stretched the original Indianapolis–Marion County Public Library, Central Branch to its limit. In response to the growth, a 350,000 ft2 addition was proposed. The completed project would boast a 350-seat auditorium, over 300 personal computers and meeting rooms that would accommodate between 40 and 80 people. The vision of a new library complex, which would incorporate the original 1917 Historic Paul Cret building, was delayed when consolidation issues in the column heads and beams of the new addition were discovered. Structural Group of Maryland Inc. was awarded the contract to repair the suspect areas. Structural Group contacted King Packaged Materials Company to assist in the repair strategy through the use of KING MS-S10 SCC. The flowable nature of the MS-S10 SCC allowed The Structural Group to overcome consolidation challenges which were compounded because of congested re-bar. MS-S10 SCC also met all of the stringent hardened property requirements that were outlined in the specification.

The plastic properties of MS-S10 SCC were tested at the Structural Group’s office in Chicago, where a full scale mock up of a column head, including formwork, reinforcing steel and post tension cables was constructed. MS-S10 SCC was pumped into the mock-up forms, completely encapsulating the reinforcing steel, post tension cables and form hardware. MS-S10 SCC pumped with ease and filled all voids during the demonstration. Extensive testing of the hardened properties included casting of test cylinders as well as the review of historical data collected from Kings in-house quality assurance program. A special test program was also developed to measure King’s ability to provide product consistency. Results of all tests were submitted to the project engineer, Construction Technology Laboratories, Inc.

Structural Group pumped MS-S10 SCC using a Whiteman Conspray SV-12 pump with a 3” discharge through a 3” hose for most of the large area repairs. They reduced down to a 2” hose for smaller repairs and experienced no trouble pumping.The Structural Group, Inc. and Construction Technology Laboratories, Inc. were pleased with KING’s dedication to product quality, involvement in the development process and performance of the material.