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COMMERCIAL BUILDINGS OF MULTIPLE TENANTS

Posted by on 18/ 11/ 15

Commercial buildings of multiple tenants is our first topic of conversation (Fig. 9.1). This type of building can include a number of uses. Look at the table in Figure 9.1. You can see headings for water closets, lavatories, drink­ing fountains, and bathing fixtures. At first glance, the table seems simple enough, and it is not too difficult. But it can be confusing, so let’s go through some sizing examples.

Подпись: been there done that As a young plumber, I thought the codebook was easy to deal with. Once I started being held responsible for my own code decisions, I found that the presentation of the code was not as clear as I once thought it was. Take some time to work with your codebook before you need it. Learn how to use the information in the code to your best ad-vantage. This is best done with practice. Set yourself up with hypothetical circumstances and use your codebook to solve problems and answer questions. Check with a master plumber, when needed, to see if your solutions are correct. This will make your field work much easier as you come to rely on your code skills. I want you to assume that there will be 62 people rated for the building that we are sizing. How many fixtures of each type will the building require? Take a mo­ment to work the numbers, and then read the following results to see if you arrive at the same number that I do.

if you look under the heading for wa­ter closets, you will see that you need three for men and four for women...

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The science of fluids at Alexandria under the Roman domination Heron of Alexandria and the “pneumatic” machines

Posted by on 18/ 11/ 15

The contributions of Heron of Alexandria belong for the most part to the continuum of work of Ctesibios and Philon of Byzantium. It was believed for quite some time that he lived in the 1st century BC. Now, Heron, in his work Dioptra, describes how to estimate the distance between Rome and Alexandria through observation of a lunar eclipse – an eclipse that took place in 62 AD.[198] The work of Heron therefore must be dated from the second half of the 1st century AD. The importance of this detail will appear in Chapter 6 in the context of understanding Roman treatises on aqueducts. Like Ctesibios and Philon, Heron is the author of a treatise on Pneumatics. Acknowledging his debt to earlier authors, but claiming some of his own originality, he describes a number of machines...

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Damp Basement Solutions

Posted by on 18/ 11/ 15

To find the best cure for a damp basement, first determine whether the problem is caused by water outside migrating through foundation walls or by interior water vapor inside condens­ing on the walls. To determine which problem you have, duct tape a 2-ft.-long piece of alu­minum foil to the foundation, sealing the foil on all four sides. Remove the tape after 2 days. The wet side of the foil will provide your answer. Chapter 14 has more about mitigating moisture and mold.

CORRECTING CONDENSATION

If the problem is condensation, start by insulating cold-water pipes, air-conditioning ducts, and other cool surfaces on which water vapor might con­dense. Wrap pipes with preformed foam pipe insu­lation...

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Cubic Yards of Concrete in Slabs of Various Thicknesses* t

Posted by on 18/ 11/ 15

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Подпись: ^^^AREA (sq. ft.) 1.0 in. 1.5 in. 2.0 in. 2.5 in 3.0 in. 3.5in. 4.0 in. 4.5 in. 5.0 in. 5.5 in. 6.0 in 10 0.03 0.05 0.06 0.08 0.09 0.11 0.13 0.14 0.15 0.17 0.19 20 0.06 0.09 0.12 0.16 0.19 0.22 0.25 0.28 0.31 0.34 0.37 30 0.09 0.14 0.19 0.23 0.28 0.33 0.37 0.42 0.46 0.51 0.56 40 0.12 0.19 0.25 0.31 0.37 0.43 0.50 0.56 0.62 0.68 0.74 50 0.15 0.23 0.31 0.39 0.46 0.54 0.62 0.70 0.77 0.85 0.93 60 0.19 0.28 0.37 0.46 0.56 0.65 0.74 0.83 0.93 1.02 1.11 70 0.22 0.32 0.43 0.54 0.65 0.76 0.87 0.97 1.08 1.19 1.30 80 0.25 0.37 0.49 0.62 0.74 0.87 1.00 1.11 1.24 1.36 1.48 90 0.28 0.42 0.56 0.70 0.84 0.97 1.11 1.25 1.39 1.53 1.67 100 0.31 0.46 0.62 0.78 0.93 1.08 1.24 1.39 1.55 1.70 1.85 200 0.62 0.93 1.23 1.54 1.85 2.16 2.47 2.78 3.09 3.40 3.70 300 0.93 1.39 1.85 2.32 2.78 3.24 3.70 4.17 4.63 5.10 5.56 400 1.23 1.83 2.47 3.10 3.70 4.32 4.94 5.56 6.17 6.79 7.41 500 1.54 2.32 3.09 3.86 4.63 5.40 6.17 7.00 7.72 8.49 9.26 600 1.85 2.78 3.70 4.63 5.56 6.48 7.41 8.33 9.26 10.19 11.11 700 2.16 3.24 4.32 5.40 6.48 7.56 8.64 9.72 10.80 11.88 12.96 800 2.47 3.70 4.94 6.20 7.41 8.64 9.88 11.11 12.35 13.58 14.82 900 2.78 4.17 5.56 6.95 8.33 9.72 11.11 12.50 13.89 15.28 16.67 1,000 3.09 4.63 6.17 7.72 9.26 10.80 12.35 13.89 15.43 16.98 18.52
Подпись: This table can be used to estimate the cubic content of slabs larger than those shown. To find the cubic content of a slab measuring 1,000 sq. ft. and 8 in. thick, add the figures given for thicknesses of 6 in. and 2 in. for 1,000 sq. ft. f Courtesy of Bon Tool Company, © 2003, from Statistical Booklet: Contractors, Tradesmen, Apprentices (see also www.bontool.com).

slabs consist of 4 in. of concrete poured over 4 in. of crushed rock, with a plastic moisture barrier between. In addition, garage floors are often reinforced with steel mesh or rebar to support greater loads and forestall cracking.

PREP STEPS

As with any concrete work, get plenty of help. Concrete weighs about 2 tons per cubic yard, so if your slab requires 10 cu. yd., you’ll need to move and smooth 40,000 lb. of concrete before it sets into a monolithic mass. Time is of the essence, so make sure all the prep work is done before the truck arrives: Tamp the crushed stone, spread the plastic barrier (minimum of 6 mil), and elevate the steel reinforcement (if any) on
dobie blocks or wire high chairs so it will ride in the middle of the poured slab...

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Size Determination for Culverts with Outlet Control

Posted by on 18/ 11/ 15

The headwater depth for a culvert operating under outlet control may be determined with the aid of the outlet control nomographs in HDS 5. An example of these nomo­graphs for box culverts is shown in Fig. 5.15. The following procedure may be used to determine the head H from the nomographs. The length L (ft), entrance coefficient ke, and design discharge must be known. Locate L on the appropriate ke curve, and connect this point with the proposed culvert size. Locate the design discharge and extend a line from that point through the turning point intersection of the previous line to read the

Size Determination for Culverts with Outlet Control

FIGURE 5.14 Flow nomograph for box culvert under inlet control. (From “Hydraulic Design of Highway Culverts," HDS 5, FHWA, with permission)

value of the head H (ft) on the right...

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Capping a Foundation

Posted by on 18/ 11/ 15

Capping an old foundation with new con­crete is relatively rare but is done when the existing foundation is in good condition and needs to be raised because the house’s framing is too close to the ground, allowing surface water to rot sills and siding.

To raise wood members sufficiently, the new cap must be 8 in. above grade. At the very least, that means shoring up the structure, removing the existing mudsill, shortening the pony-wall studs, drilling the old foundation, epoxying in rebar pins to tie the new concrete to the old, and pouring new concrete atop or around some part of the existing foundation. That’s a lot of work. So if the existing founda­tion is crumbling or lacks steel reinforcement, you should replace it altogether.

On the other hand, if the house lacks pony walls and th...

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CALCULATING MINIMUM PLUMBING FACILITIES

Posted by on 18/ 11/ 15

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Подпись:alculating minimum plumbing facilities is a common part of a master plumber’s job. Knowing and understanding what is required in a build­ing is not only a requirement for plumbers. Architects and engineers are often the people who determine the requirements for a new building. Local plumbing codes dictate minimum plumbing facilities. All plumbers have to do is understand the information provided for them in their codebooks. The in­formation given by the codes is fairly simple, but gaining a complete under­standing of it can be a bit intimidating. If the process is approached too lightly, mis­conceptions can cause mistakes. The peo­ple responsible for determining what plumbing will be included in a building cannot afford to make mistakes.

CALCULATING MINIMUM PLUMBING FACILITIESПодпись: ► sensible shortcutIt is common for plumbers to be pro­vid...

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Size Determination for Culverts with Inlet Control

Posted by on 18/ 11/ 15

Once the design discharge and allowable headwater are determined and the culvert alignment and slope decided upon, an efficient culvert size may be found through the use of nomographs as shown in “Hydraulic Design of Highway Culverts,” Hydraulic Design Series 5, FHWA.

An example of an inlet control nomograph is shown in Fig. 5.14. Since the structure size is not known, the design is an iterative process. To use the chart, the trial culvert size and inlet configuration, design discharge, allowable headwater depth, culvert length, and culvert slope must be known...

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Water Vapor Infiltration

Posted by on 18/ 11/ 15

The infiltration of water vapor as a soil gas is a common problem that may be due to several conditions, including high water tables, un­derground springs, or hardpan soils that cause excess water to remain at the surface. Certain soils hold moisture so that, instead of perco­lating through the soil, water vapor evaporates and travels upwards. Even with proper perim­eter drainage around the building, which will take care of flowing water, this residual water vapor maybe sufficient to cause damage.

Soil Gas Mitigation and Prevention

Foundation detailing and design affect the amount of soil gases that will accumulate in a building if they are present in the soil...

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Allowable Headwater Depth

Posted by on 18/ 11/ 15

The allowable headwater depth is the depth of ponded water permitted at the entrance to a culvert. Allowable headwater depths are generally classified as either physical controls or arbitrary controls.

Physical headwater controls are topographic features that should be protected against periodic inundation. They include the roadway pavement and upstream pro­ductive property or structures. Additionally, high points between adjacent watersheds should typically be used as physical headwater controls. The use of a watershed break elevation as a headwater control will protect against the unnecessary diversion of runoff from a watershed to an adjacent watershed.

Arbitrary headwater controls are typically used to ensure the efficient operation of the culvert while protecting the roadway embankme...

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