Structural Foundation Slab - Essay Example

Introduction The base floor of the building is simply a cast-in-place concrete slab on grade and has in place limited design considerations used in structural support or environmental control considerations. It is also comprised of a structural foundation slab fully equipped with waterproofing as well as wearing slab with overall system designed to be able to carry structural hydrostatic pressure loads, in addition to maintaining a regulated environment. It takes not of the fact that floor slabs are in many instances, the source of leakage into building, with slab cracks of regular concrete materials being the main culprit. Additionally, there are issues of regulating soil gas emissions including radon. Description of the floor finishes Finish Floor Coverings The floor finish for all the floor do not include exposed concrete surfaces; rather, floor coverings including wood, vinyl floors and carpets are used in the floor finishes exposed region. Additionally, the adhesives used in application of floor coverings are sensitive to moisture requirement of use of a waterproof system or long drying durations where poly vapor retarders are used. The concrete floor slab comprise of a 4" to 6" thick concrete reinforced with a layer of welded wire fabric at mid-depth. The under slab vapor retarders include polyethylene, polyolefin, high density bonded polyethylene, and asphalt composite/polymer modified sheets. Poly sheets are 15 mils thick and have taped seams, edges, as well as penetrations. The vapor retarders were selected as per ASTM E 1745 and E 1993 and installation and inspection is to be based on ASTM E 1643. Fundamentals This section describes each floor and provides a schematic drawing of its structural Support, Environmental Controls, Finishes, and Distribution system in relation to the below grade enclosure floor slab elements. Exterior environment, to which the floor slab is subjected, includes environmental regulated loadings including thermal, moisture, insects, as well as any soil gases. The interior environment to which the floor slab is subjected to includes environmental control loads like thermal and moisture. Performance of floor slab system heavily depends on the slabs ability to control, regulate and moderate the environmental control loads on floor slab interior to desired levels. First Floor Floor Determination Poor bearing capacity of soils Condition of existing structure Design and code parameters Need : Light weight vertical addition Solution : Composite concrete & steel deck on steel structure 2nd floor 3rd floor The floor slab of below grade building enclosure is designed to carry downward vertical gravity loads as well as upward soil or hydrostatic pressure loads. The key objective was to avail a waterproof membrane/vapor retarder below floor slab. A vapor retarder can resist vapor migration in absence of hydrostatic pressure. Water-proofing helps in resisting both vapor migration and hydrostatic pressures. Generally, the vapor retarder is installed between granular drainage and floor slab. This layer also helps in minimizing shrinkage stresses as well as floor cracking as a result of reduction in shrinkage restraint. Finish Functions are simply concerned with interior space. This finish depends on interior use. As already mentioned, the finishes used in this case are adhered floors. Floor finish is an important part of interior finishes and the kind of materials used ultimately dictate the quality of finish and appearance of a room or the entire building. Floor is largest surface in a building exposed to high friction levels and hence vulnerable to excessive wear due to extensive usage (Brown, 2002). It is therefore important to focus on a floor finishes’ performance characteristics before looking at aesthetics. Common floor finish materials include carpets, stones, ceramic tiles, wood as well as resilient flooring materials such as vinyl tiles, linoleums, and corks. It is also important to take note of accessibility codes which limit height variation of adjacent flooring materials to half-inch; an important consideration at door thresholds and well as locations of material transition from one type to other (Tomio & Fiornio, 2009). A number of materials re used in floor finish for this building. Carpets Carpet floorings are proposed for used in several parts of the building. They are recommended due to their positive attributes which make the carpets; both broad-loom goods and carpet tiles, widely used in floor areas. The material has good acoustic properties, are easy to maintain, and are relatively inexpensive, in addition to offering, abundant aesthetic opportunities. Its choice is motivated its long-lasting characteristic and can last up to four years before a replacement is required. Dense carpets are appropriate and hence recommended. It has a minimum of 50% loop pile yarns, not light in color, and not very solid in appearance. Carpet tiles Use of carpet tiles has increasingly grown over the last ten years. The larger size measuring 36” x 36” size is proposed. This is meant to lower the number of seams without compromising possibility of replacement or repair when necessary. They will also offer raised access floor, and offer a plenum below for mechanical, electrical, as well as telecommunications services. The carpets tiles support greater flexibility due to use of access floor system. It will further offer tiles which “snap” on to raised floor instead of raising necessity for adhesives, despite the costs being slightly higher. This is also advantageous when looked at from the green production perspective. The tiles also offer an opportunity to introduce new design patterns and hence improve aesthetics. Further, installing tiles in ashlar/staggered pattern provides a brickwork effect, while combination of 18” and 36” tiles yields border and field effect. Limestone and marble Limestone is neutral in color while marble; a metamorphosed limestone has minerals which offer it all color possibilities. Due to the fact that marble and some limestone are hard, they can be polished to achieve a highly reflective sheen. This will be used in some of locations on the floor. Terrazzo Terrazzo is man-made and is a composite material consisting of stone aggregate mixed chips and set in a filler/binder, known as matrix. They take the form of a mosaic and hence aesthetics of the floor can be altered to take various colors forms, chip sizes, aggregate to matrix proportion as well as matrix color. Matrices use either, polyester resins or epoxy or even a combination of both. They will allow not just color control but also consistency which makes it an excellent material to create a multi-colored pattern and design. Its sections will be partitioned using divider strips which help in preventing cracks. When this flooring is installed, it is ground and polished rather than high sheen. They are chosen because they require low maintenance and are also durable. However, just like polished stone floors, they will require treatment using a slip-resistant sealant to set coefficient of friction to meet code requirement. Minimum slip coefficient of friction recommended is 0.5, and accessibility codes recommended are 0.6. Resilient flooring These are floors which repel liquids and dirt and are made from either, synthetic materials like vinyl or natural materials like linoleum and cork. They are affordable, durable, and easily to clean, let alone mention that they require low maintenance, and provide an opportunity for multiple design possibilities. They are mostly usable in places where liquids are present including staff lounges, activity rooms, technical services, as well as storage rooms. A base of vinyl is used. The vinyl tiles used are 12” x 12” square. They will allow attainment of interesting design and patterns and insertion of different colors and border options. Ceramic tiles The ceramic tiles are man-made fired clay tiles and are high appropriate for long wear-out floor surfaces in a library. They will mainly be used in the kitchens and commercial restrooms. The ceramic tiles can be installed, either thin-set (adhesives) or in thicker mortar-bed base with grout joints which range from 1/8” to 1/4”. This chosen due to its durability and ease of maintenance, in addition to the fact that is dimensionally consistent and stable. Other floor finishes to be used will include two natural resilient flooring materials, that is, linoleum and cork, and porcelain tiles which are hard, with some actually approaching granite hardness. There sizes are 24” x 24”, because they have porcelain material in base and therefore fired at a higher temperature in fusing the materials together. Hardwood flooring will also be used since it is fairly expensive and appropriate in special collections rooms as well as main reading rooms, where it gives a warm, welcoming, and rich appearance. Oak and maple will be alternated. Oak takes stain well and ranges from white-washed and clear finishes to medium to darker tones. Maple is a very condensed fine grain, fairly uniform in appearance, and also possesses less texture as compared to oak. It is light in coloration and, hard, and non-porous. References Brown, C. R. (2002). Interior Design, Drawing on Function and Appeal. Chicago: American Library Association Tomio, P. & Fiornio, F. (2009). The Porphyry Manual. Trento, Italy: Commissioned by E.s.po., Publistampa Arti Grafiche Read More