FLATWORK/SLABS
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BY MIKE THOLEN
A Focus On Slabs Updates to CCS-1(10) Slabs-on-Ground from ACI’s Concrete Craftsman series.
The document covers: • Slab-on-Ground Planning—CCS1(10) Slabs-on-Ground discusses factors to consider when determining appropriate placement size, including variables in production rates, weather and operator experience. It explains he American Concrete Institute the way concrete quantities are (ACI) produces hundreds of doccalculated, details regarding ordering uments dedicated to improving concrete, and lays out requirements the design, construction, maintenance, for handling concrete delivery. and repair of concrete and masonry Discussion of crew size, required structures. ACI documents are develequipment, and procedures to follow oped in numerous types and formats, during preconstruction meetings including standards, handbooks and further help the manuals, certification reader understand the documents, and edufirst phase of concrete cation documents. slab placement. One group of ACI • Basic Concrete education documents Materials, Mixture that has been gaining Proportioning, and in popularity over the Testing—Chapter years is the Concrete 2 briefly explains Craftsman series, concrete materials, a useful guide and how they are training resource combined in mixture for craftsmen and proportioning to contractors, especially American Concrete Institute obtain fresh and those interested in hardened concrete properties, and how earning credentials by becoming ACI to measure those with control tests. certified. It is also of interest to persons • Preparation before Concrete who are peripherally involved with Placement—This section details how the concrete industry, such as material to prepare and compact the subgrade; supplier representatives or inexperienced accomplish elevation control; engineers who are looking to increase determine the placement sequence; set their knowledge of construction side forms, temporary bulkheads, and materials. Titles in the Concrete screed guides; install vapor retarders Craftsman series include Concrete and/or reinforcement (if required); Fundamentals, Slabs-on-Ground, lay out and mark joint locations on Shotcrete for the Craftsman, Supported forms, and a checklist of necessary Beams and Slabs and Placing and tools and materials. Finishing Decorative Concrete Flatwork. • Floor Flatness and Levelness—Floor CCS-1(10) Slabs-on-Ground was the flatness is important when wheeled first book issued in the ACI Concrete vehicles will operate on a slab and for Craftsman Series. The most recent floors where thin vinyl sheet goods edition was updated with information to or polishing will be installed. This include placing with laser-guided screeds section explains how to measure floor and finishing with walk-behind and flatness and levelness and addresses riding power equipment.
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areas of concern when constructing floors to tight requirements. • Placing and Finishing Equipment— Chapter 5 points out the importance of placing concrete without delays and without changing the concrete properties, in order to best facilitate proper concrete finishing. Methods discussed include direct placement from truck mixers as well as placement from manual or motorized buggies. For multistory buildings, crane and bucket placement, concrete conveyors and pumps are common placement methods defined. Tools used by laborers to complete placement and achieve finishing include spreading tools, consolidating or vibrating tools, and screeds. After placement, floats, trowels, and straightedges may be used for smoothing the concrete. Jointing and edging tools, as well as power saws, may be used to install contraction joints. A broad selection of such tools are pictured, and their use explained, in Chapter 6. Once readers are familiar with placing and finishing tools, CCS-1(10) Slabs-onGround details how the tools should be used, and in which applications. Considerations such as waiting periods and managing bleed water are included. • Jointing—Concrete slabs are jointed to control cracking associated with the material’s shrinkage as it dries. CCS-1(10) Slabs-on-Ground describes the basic types of joints used as well as how to install them. The benefits of joint filling, along with sealant types and installation steps, are also covered. • Concrete Curing and Protection— Curing refers to methods used to keep concrete moist and at the temperature needed to develop the required strength, wear resistance, and durability. Climate conditions— especially temperature—heavily
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