Blog Archives

HOUSES

Posted by on 18/ 11/ 15

We’ve been dealing with commercial-type space, but let’s switch over to houses. There are times when plumbers are the ones who must figure the min­imum requirements for houses. This is especially true in very rural areas. Fig­ure 9.5 provides the information needed to compute the fixture requirements for a typical, single-family home. The same table can be used to figure the fix­ture requirements for an apartment building. Check back to Figure 9.2 for ex­planations of the numbers noted in the headings of the table. There is no big secret to this table. Each home is required to have a minimum of one toilet, one lavatory, one bathing unit, one kitchen sink, and one connection for a washing machine.

if you look at the table closely, you will see that the basic minimums are required for ea...

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Underlying Layer’s Maximum Temperature

Posted by on 18/ 11/ 15

The limitation of minimum temperatures of SMA laydown has been commonly understood and adopted; however, it is quite a different matter when laying down the SMA mixture on an underlying layer that has an excessive temperature, as in the following examples:

• On a recently placed intermediate course that has not yet cooled

• While hot recycling in situ (or in place) with the simultaneous placement of a new wearing course, so-called hot remix plus

• During the execution of the so-called Kompaktasphalt—the laydown and compaction of two courses (intermediate and wearing) at the same time with one passage of a paver (see Section 10.5).

As a general rule (see Section 10.4), rollers compacting an SMA layer operate directly behind the paver...

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A JIG FOR MARKING PLUMB CUTS IN RAFTERS

Posted by on 18/ 11/ 15

2. Then nail on a 1×2 fence.

1. Mark cut lines with a small rafter square.

A JIG FOR MARKING PLUMB CUTS IN RAFTERS

 

lx stock, the same width as rafters

 

A JIG FOR MARKING PLUMB CUTS IN RAFTERS

If you need to make a series of plumb cuts to match and align rafter tails along an eave, make a jig like the one shown here. Use a rafter square to mark the plumb-cut angle of tie roof (4-ІП-12 or 5-in-12) on a short length of 1×4 or 1×6, depending on the rafter size. Cut a parallelogram-shaped template with
identical plumb-cut angles, then nail a short 1×2 fence to the upper edge of the template. Once a chalkline has been snapped across all the rafter tails, use this template to mark the plumb cut on them so that they can be cut to length.

Подпись: over first board. Nail through miter joint, into end of truss.

MITERING FASCIA BOARDS

CUTTING AND NAILING GUIDELINES FOR GUT­TER AND FASCIA BOARDS...

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Loads

Posted by on 18/ 11/ 15

Introduction. Loads acting on buried structures include the dead load of the struc­ture itself, the dead load of the earth cover over the structure, the weight of the fluid within the structure, live loads from vehicles, and, under certain circumstances, exter­nal hydrostatic pressure from groundwater.

The structure dead load is only significant for rigid structures. Flexible structures are manufactured from plastic or metal. In each case, the weight of the material is insignificant when compared with the total load on the structure. For rigid structures, however, because the material is generally concrete and because the pipe wall thick­ness is considerable, the weight of the material should be included in the determination of the total load applied on the structure...

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Install step flashing at roof – wall intersections

Posted by on 18/ 11/ 15

Use metal step flashing to waterproof the inter­section where a roof butts into a wall. Usually made from aluminum or copper, metal step flashing is bent to form a series of elongated, L-shaped pieces that are lapped over each other in successive shingle courses as well as upward along the wall. The step flashing we used on this house is 10 in. by 6 in., and each leg is 3 in. wide.

Подпись:

Install step flashing at roof - wall intersections

The illustration on p. 144 shows how step flashing is installed on each course of shingles that runs into a wall. (It’s also used where shingles meet a chimney or a skylight curb.) Each time a regular shingle is laid down, a step shingle is placed under it—on the part of the regular shingle that will be covered. Lap step shingles by about 2 in., one on top of the other...

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Water and Soil Storage

Posted by on 18/ 11/ 15

As physico-chemical and biological reactions occur in the soil and the water, sam­pling periods of short duration are recommended. Some chemical variables should be measured in-situ in a sub-sample (temperature, pH, redox potential, and electrical conductivity) whereas the main water sample is preserved to prevent reduction or loss of target analytes, and transported to the laboratory without delay and kept cool until further treatment. Preservation stabilizes analyte concentrations for a limited period of time. Some samples have a very short holding time (from few hours to some days).

Each analytical method available will have its own requirements for specimen preparation. The most appropriate sampling method specifications for each para­meter can be found in many textbooks (e. g...

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RESTAURANTS

Posted by on 18/ 11/ 15

Подпись: ✓ fast code fact If you are a residential plumber, be aware that code requirements for commercial work can be very different from what you are accustomed to working with. Be sure that you are using the proper section of the code for the type of work that you are doing. There are a lot of restaurants in society. This is a common type of building for plumbers to work with. Finding the number of water closets and lavatories re­quired in a restaurant is no more difficult than the other examples that we’ve been working with. However, there are additional requirements for restaurants.

Essentially, you must check with your lo­cal code office and comply with minimum requirements that are established by the Board of Health.

Before we do a sizing example for a restaurant, let’s discuss two alternative op­tions. You will notice if you look at the headings in Figure 9.4, that the number 6 and the number 17 are next to the heading for restaurants...

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Make the Attic Accessible

Posted by on 18/ 11/ 15

CODE REQUIRES AN ACCESS HOLE

for the attic. This allows workers to get into the attic to install insulation and wiring. You may also want to get up there some day to check on a roof leak or just to see how the spi­ders are doing.

The standard attic access hole has a rough 2x frame that is 22/ in. wide by 31 in. long. This rectangular opening fits nicely between ceiling joists installed on 2-ft. centers. Usually, the hole is located in a closet or along a hallway. Once you select a spot for access to the attic, cut a pair of 2x$ to lit between the ceiling joists and nail them 31 in. apart. The bottom edges of the blocking should be flush with the bottom edges of the joists. Take the time to measure the hole diagonally to

make sure its square. After V*-in...

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STEP4 Secure the Trusses to the Interior Walls

Posted by on 18/ 11/ 15

On small houses, trusses are generally engi­neered to obtain their support from exterior walls without needing further support from interior walls. Still, its not uncommon for trusses to cross over and bear on interior walls. Inmost regions, these trusses can usually be nailed directly to the interior wall with two 16d toenails on one side and one on the opposite side. T his is not the case, however, if you live in a part of the country where the weather may be freezing one day and boiling the next. In areas with extreme temperature fluctuations, trusses must be able to expand and contract freely. Otherwise, drvwall ceilings

nailed to these trusses tend to crack. Check with your building department for the code requirements in your town or city...

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Some One-Dimensional Numerical Integration Formulas

Posted by on 18/ 11/ 15
Подпись: I = Подпись: b f (x) dx a Подпись: (4A.1)

This appendix summarizes some commonly used numerical formulas for eval­uating the following integral:

Detailed descriptions of these and other numerical integration procedures can be found in any numerical analysis textbook.

4A.1 Trapezoidal rule

For a closed integral, Eq. (4A.1) can be approximated as

1 = hif 1 + 2 Щ fi + (4A.2a)

where h is a constant space increment for discretization, n is the number of discretization points over the interval (a, b), including the two end points, and fi is the function values at discretized point, xi.

For open and semiopen integrals, Eq. (4A.1) can be computed numerically as

1 = h (эf2 + 2£ fi + 3fn-1^ (4A.2b)

4A.2 Simpson’s rule

For closed integrals, one has

h

1 = 3 [ f 1 + 4( f 2 + f 4 + f 6 + ■ ■ •) + 2( f 3 + f 5 + f 7 + •• •) + f...

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