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Terminology Used for Standard Pavement and Associated Drainage Items

Posted by admin on 26/ 11/ 15

The purpose of this document is to show some standard designs for pavements and associated drainage items and to present the names of these in several languages. The diagrams contained within each section show the general layout only. No detail is included regarding the specifications of the materials or specific dimensions. Many of the figures in this Appendix have been adapted and simplified from drawings made available courtesy of the Highways Agency (Manual of Contract Documents for Highway Works, Volume 3 – Highway Construction Details, Section 1 “Carriageway and Other Details” (March 1998, updated with amendments including November 2005, May 2006 & November 2006))...

Stage 1: Selecting an Aggregate

Posted by admin on 26/ 11/ 15

Requirements for aggregates to be used in SMA are catalogued in Chapter 5. When differences among densities of aggregates used for composing an SMA aggregate

* 2.36 mm in the United States, 2.0 mm in Europe.

[30] NMAS stands for nominal maximum aggregate size—a sieve one size larger than the first sieve retaining more than 10% of the aggregate.

[31] Fill the container with aggregate up to one third of its height, level the surface of the poured aggregate using your fingers, and then tamp the layer down with 25 strokes of the tamping rod, taking care to evenly distribute the strokes over the surface and avoiding hitting the bottom of the container (Figure 7.7).

[32] Having completed the tamping of the first layer of aggregate, fill the container with a second layer of aggregate—this ti...

Afterword

Posted by admin on 26/ 11/ 15

A few years ago, at the beginning of the work on this book about SMA, I did not suppose it would take on such imposing proportions. Meanwhile, over the course of work on the publication, it turned out that the quantity of accessible materials on SMA was really spectacular, and the range of SMA-related subjects was enormous. While carrying out a survey on relevant publications, it became noticeable that SMA was still a fascinating asphalt mixture to many process engineers the world over.

All in all, it would be appropriate to finish briefly, in contrast to the content of the book, which might seem to be a bit verbose here and there. Nevertheless, I do hope that it will help its readers comprehend SMA and clear up any problems that might arise.

It is a matter of course that the examples quot...

Derivation of Water-Quality Constraints

Posted by admin on 26/ 11/ 15

In a WLA problem, one of the most essential requirements is the assurance of a minimum concentration of dissolved oxygen (DO) throughout the river system in an attempt to maintain desired levels of aquatic biota. The constraint relating the response of DO to the additional of in-stream waste generally is defined by the Streeter-Phelps equation (Eq. 8.60) or its variations (ReVelle et al., 1968; Bathala et al., 1979). To incorporate water-quality constraints into the model formulation, a number of control points are placed within each reach of the river system under investigation. By using the Streeter-Phelps equation, each control point and discharge location becomes a constraint in the LP model, providing a check on water-quality at that location...

Denmark

Posted by admin on 26/ 11/ 15

The Danish design system deals with seasonal variations by adjusting the expected bearing capacity (E-modulus) of each pavement layer. In the design software MMOPP (Mathematical Model of Pavement Performance) (Ullidtz, 1993) the user can choose an advanced design procedure, where the performance of the road is simulated over (for example) 40 years. The program is given constant E-modulus values as material parameters for each pavement layer. These moduli are then varied over the seasons as shown in Table A.1. The constant E-values given as input represent the summer values. In wet seasons the E-moduli of unbound layers are reduced. In frost seasons the values are increased.

Table A.1 Coefficient multiplied to the E-value dependent on season and layer

Season

No. of days/year

A...

About the Author

Posted by admin on 26/ 11/ 15

Jay Shafer is leading a movement that is changing the way America views housing. His revolutionary approach to house design has stirred international dialogue. In his, The Small House Book (self-published, 2000), Shafer explains why smaller dwellings make good sense and how superior design can be achieved with less space. He has continued to share his philosophy by creating Tumbleweed Tiny House Company through such venues as Fine Homebuilding,

The Wall Street Journal, The Oprah Winfrey Show, and at the University of Iowa’s School of Art, where he served as Adjunct Assistant Professor of Drawing for more than a decade. Professor Shafer currently lives in a 89 square foot home of his own creation.

Visit www. tumbleweedhouses. com for more about Jay and Tumbleweed Tiny House Compan...

FREESPANNING-STAIR BALUSTRADE

Posted by admin on 26/ 11/ 15

STAIRS

Handrails

Handrails provide stability and security for the young, the old, the blind, and the infirm. In addition, handrails are a safety feature for anyone who uses a stairway—one of the most likely and dangerous places for people to trip and fall.

In terms of safety, the most important design feature of a handrail is its ability to be grasped, especially in an emergency. The іУз-іп. to 2-in. round rail is the most effective in this regard, as it allows the thumb and fingers to curl around and under the rail. Other shapes are allowable by code, but are less graspable.

The height of the handrail is usually specified by code. Most codes fall within the range of 29 in. to 36 in. above the nosing of the stairs...

John Banta

Posted by admin on 26/ 11/ 15

My introduction to the downside of indoor air quality occurred along with my introduction to fatherhood in 1980. Like many first-time parents, my wife and I wanted to welcome our newborn by decorating the nursery. We painted and carpeted the room in anticipation of our new arrival. The room smelled of chemicals and I noticed that I did not feel well in there. But it wasn’t until our baby became ill that I realized what a serious problem we had created. By the time I made the connection between my daughter s medical condition and the toxins in the nursery, she had become sensitized to even minute amounts of toxic chemicals commonly found in the environment and was in severe distress. My wife and I decided to buy an old Victorian home that had not been remodeled in over 40 years...

Additional Tests of Asphalt Mixture Characteristics

Posted by admin on 26/ 11/ 15

The previous deliberations on FPC use a basic level applied to the standard EN 13108-21 regarding tests of the mixture composition. Meanwhile methods of testing other properties of an asphalt mixture are discussed in Annex D (and are very informative). Collected results should be declared and used to support the procedure of extended validation of type testing.

The SMA mixture characteristics that are tested include the following:

• Content of air voids in compacted samples (% v/v) according to EN 12697-8

• Properties of the binder of RAP (only in case of recycled asphalt in an SMA paving mixture) according to EN 12697-4 and EN 12697-3

• Penetration at 25°C according to EN 1426

• Ring and ball (R&B) softening point according to EN 1427

Sampling and testing additional physical pr...

. A STAIR LANDING

Posted by admin on 26/ 11/ 15

Подпись: NEWEL POST NEWEL POST

Surface Anchored

2 Alternatives

The advantage of the skirt over the housed stringer (see 217B) is the ease of construction. A disadvantage is the potential for minor opening of butt joints at the ends of treads and risers due to minor movement of the structure. A more involved hybrid strategy that limits this disadvantage is to install the risers first from wall to wall, cut out the stringers to fit to the risers, and finally install the treads tightly between the stringers.

Подпись: FiNiSH TREADS & RiSERS BUTT AGAiNST THE SKIRT & ARE GLUED & NAILED TO CARRIAGE ON WHiCH THEY ARE SUPPORTED. FOR TREAD & RISER SECTIONS, SEE 216. - Подпись: FiNiSH STRINGER FITS BEHIND cARRiAGE & IS APPLIED DIRECTLY To FiNiSH WALL. Подпись: SPACER NAILED TO STUDS . A STAIR LANDING

Подпись: The housed stringer is a more refined and complicated way than the skirt (see 217A) to provide a finish stringer at the side of a continuously supported stairway. The advantage of the housed stringer is that joints between treads, risers, and finish stringer will not open up with shrinkage or other minor movement of the structure. Disadvantages include the extra labor to build the housed stringer and the fact that it does not provide the framing for a temporary construction stair. Good- quality prefabricated stairs (see 213C) are also made with housed stringers.

дЬ FINISH STRINGER (SKIRT) AT FINISH WALL

structed between two walls. The skirt on the open side

. A STAIR LANDING

OPEN BALUSTRADE

With Curb

. A STAIR LANDING
дА OPEN BALUSTRADE

Подпись: . A STAIR LANDING Подпись: FRAMING TO STIFFEN BASE AS FOR NEWEL POST SEE 215B& C The closed balustrade is veiy economical to build because it involves the least finish work of any balustrade system...