During 11 May–October 2012 pours totaling 1,600 yd.
of SCC, the producer agreed to pre-load drum inspections and individual load sampling, typically by contractor and architect representatives, plus in-house technicians; one load only per truck per pour; and, provision of full back up fleet/plant redundancy, where 15 or more mixers were idled during each pour, but ready to load at a back up plant in the event of a main plant breakdown.
Bury also noted an ACI Certification Committee C610 feasibility study for an SCC Field Technician Certification program encompassing C1758, C1611, and C1712 methods.
ACI C610 and ASTM C09.47 members would benefit from a review of the mix acceptance protocol Breckenridge Material Co., Mc Carthy Building Cos. Louis Art Museum East Building, whose coffer beam ceilings—as this month’s cover shows—are a stellar example of exposed, cast-in-place SCC.
It has also found application in architectural concrete because of its ability to create smooth surfaces free of honeycombing when used with high-quality formwork.
Applications of self-consolidating concrete also include columns and beams, pumped concrete, foundations, and other applications where a flowing concrete will be beneficial to concrete placement.
In an “An Overview of ASTM Standards Related to Self-Consolidating Concrete,” BASF Construction Chemicals Product Manager Mark Bury discussed the emergence of ASTM Subcommittee C09.47 on Self-Consolidating Concrete amid rising, early 2000s adoption of SCC, especially among precast producers.
Further adoption for cast-in-place structures has confirmed the usefulness of four C09.47 products through 2012: C1758 Standard Practice for Fabricating Test Specimens with Self-Consolidating Concrete, addressing concerns that conventional concrete specimen methods do not necessarily suit SCC; C1611 Standard Test Method for Slump Flow of Self-Consolidating Concrete, monitoring the consistency and unconfined flow potential of fresh material in field or laboratory conditions; C1610 Standard Test Method for Static Segregation of Self-Consolidating Concrete Using Column Technique, measuring the coarse aggregate content in a cylindrical specimen’s top and bottom portions; and, C1712 Standard Test Method for Rapid Assessment of Static Segregation Resistance of Self-Consolidating Concrete Using Penetration Test, primarily gauging a mix’s segregation potential.
Improved consolidation around reinforcement and bond with reinforcement Improved pumpability.Louis Art Museum East Building, Breckenridge Material has set a new standard for SCC in architectural conditions.Self consolidating concrete (SCC), also known as self compacting concrete, is a highly flowable, non-segregating concrete that can spread into place, fill the formwork and encapsulate the reinforcement without any mechanical consolidation.Improved and more uniform architectural surface finish with little to no remedial surface work.Ease of filling restricted sections and hard-to-reach areas.The in-place cost savings, performance enhancements, or both, are the driving forces behind the use of self-consolidating concrete.It is often used where reinforcement is highly congested or in areas of complex formwork.The fifth North American Conference on the Design and Use of Self-Consolidating Concrete, or SCC 2013, offered strong market and technical perspectives on one of the industry’s best value propositions to the architectural/engineering/construction community of the past two decades.Presenters at the mid-May event in Chicago demonstrated how stakeholders have compelled American Concrete Institute and ASTM International committees to develop guidelines and standards indicating self-consolidating mixes’ quality in plastic and hardened states.The flowability of SCC is measured in terms of spread when using a modified version of the slump test (ASTM C 143).The spread (slump flow) of SCC typically ranges from 18 to 32 inches (455 to 810 mm) depending on the requirements for the project.