Laboratory concrete

Some ITRs will come from other parties, such as surveyors, laboratories, concrete batching plants and suppliers and will in each case have a format specific to the organization concerned. 

D. Whiting u. D. Stark, Cathodic Protection for Reinforced Concrete Bridge Decks B Field Evaluation, Final Report, Construction Technology Laboratories, Portland Cement Association, Skokie, Illinois, NCHRP 12-13A (1981). 

CP-1 was assembled in an approximately spherical shape with the purest graphite in the center. About 6 tons of luanium metal fuel was used, in addition to approximately 40.5 tons of uranium oxide fuel. The lowest point of the reactor rested on the floor and the periphery was supported on a wooden structure. The whole pile was surrounded by a tent of mbberized balloon fabric so that neutron absorbing air could be evacuated. About 75 layers of 10.48-cm (4.125-in.) graphite bricks would have been required to complete the 790-cm diameter sphere. However, criticality was achieved at layer 56 without the need to evacuate the air, and assembly was discontinued at layer 57. The core then had an ellipsoidal cross section, with a polar radius of 209 cm and an equatorial radius of309 cm [20]. CP-1 was operated at low power (0.5 W) for several days. Fortuitously, it was found that the nuclear chain reaction could be controlled with cadmium strips which were inserted into the reactor to absorb neutrons and hence reduce the value of k to considerably less than 1. The pile was then disassembled and rebuilt at what is now the site of Argonne National Laboratory, U.S.A, with a concrete biological shield. Designated CP-2, the pile eventually reached a power level of 100 kW [22]. 

FIGURE 12.39 (o) Vortex exhaust at a concrete element factory, h laboratory model of the vortex exhaust, and (c) stmpIKIed model of the exhaust. 

U. S. Army Engineer Waterways Experiment Station Concrete Technology Division, Structures Laboratory Vicksburg, MS 39180, USA... 

Brown and Fessler have conducted a laboratory evaluation of conductive mastics that can be brushed or sprayed onto the concrete surface to achieve the necessary thickness. However, the most extensive study on conductive paints for cathodic protection purposes has been undertaken by the Federal Highway AuthorityA total of nine commercially available resins were evaluated in this work. It was shown that neither thermal cycling, freeze thawing nor the application of cathodic protection currents... 

Except in the occasional introductions that students seldom read, science texts make little attempt to describe the sorts of problems that the professional may be asked to solve or to discuss the variety of techniques that experience has made available for their solution. Instead, these books exhibit, from the very start, concrete problem-solutions that the profession has come to accept as paradigms [as exemplars], and they then ask the student either with a pencil and paper or in the laboratory, to solve for himself problems very closely modelled in method and substance upon those through which the text has led him (italics Kuhn, 1963, p. 351). 

Chemistry is basically an experimental science, hence the contact, especially through the laboratory and practical work, with concrete examples of substances, their reactions and other properties, is an essential and integral part of chemical education. The laboratory is therefore the proper place for keeping chemistry tangible. 

FIGURE 26.40 Correlation coefficient between road test ratings on a wet concrete track and laboratory measurements on a wet blunt Alumina 180 disk. Left as function of log a- v and right as function of log a-rv and log V. 

Figure 26.42 compares the correlation coefficient between a road test on wet concrete and the laboratory side force measurements of the six compounds of Table 26.2 on blunt, wet Alumina 180 (a) with a log oxv-log v evaluation and (b) with a temperature-log v evaluation. It appears that the... 

FIGURE 26.42 Comparison of the correlation coefficients between laboratory side force measurements with the six compounds of Table 26.2 on wet, blunt Alumina 180 and a concrete road test track as function of log ajv and log v (left) with function of temperature and log v (right). 

Possible vibration sources outside the building, such as nearby railroad tracks, should be considered also. In a new testing laboratory, heavy truck traffic immediately outside caused periodic vibration problems, even though the building sat on a solid concrete slab. Had this laboratory been on an upper floor, the vibration would have been even more severe. 

The ease of access to utilities should also help determine the laboratory s location. Most laboratories will need hot and cold water, electric power, gas, and sewer connection. The cost of bringing these to a remote location may be high. The sewer is often the most problematic. Many a concrete slab has been tom up at considerable expense in order to install a laboratory sewer. A building professional should be consulted to give advice in such cases. 

Concrete, cement block, and wallboard are the most common w all materials found in laboratories. All can be painted after treatment with an approprite sealer or filler. The choice of paint is very important. Both durability and ease of cleaning must be carefully evaluated. Bargain paints are rarely a bargain in the long run, particularly when labor is such a large part of the cost. 

Asphalt concrete is properly proportioned to resist the potentially damaging effects in the road. Asphalt concrete paving mixtures should be evaluated for the following properties stability, flow, air voids, stripping resistance, resilient modulus, compacted density, and unit weight. Table 4.18 provides a list of standard laboratory tests that are presently used to evaluate the mix design or expected performance of fresh and hardened asphalt concrete. 

Unit weight, yield, and air content of concrete California Bearing Ratio (CBR) of laboratory-compactive soils Unconsolidated undrained compressive strength of cohesive soils in triaxial compression... 

The combination of kinetics, hydrodynamics and transport phenomena that provide the proper scale-up of bioreactors from laboratory to the industrial scale also has to be taken into account [4]. Different process solutions will be discussed within this chapter in detail, starting from concrete problem and illustrating possibilities to overcome this problem. 

Measurements reported herein were made in a first-floor laboratory room in a two-story classroom building having concrete floors and walls. Windows were not open and no artificial ventilation was used during the period of study. 

There were also less concrete considerations. In the early 1950s glycogenolysis was still believed to be completely reversible. UTP dependency and the glycogen synthase reactions had not yet been discovered nor had phosphofructokinase been shown to act irreversibly. The mechanism of protein synthesis was still a mystery. Laboratories studying proteolysis had shown that the peptide bond could be resynthesized by peptidases, although under very restricted conditions. Reversibility seemed to be an accepted property of the major metabolic pathways. 

North Carolina Department of Transportation Materials and Tests Unit (NC-DOT-MAT) (1993) A laboratory evaluation on crumb rubber on strength performance of concrete. Symposium proceedings Recovery and Effective Reuse of Discarded Materials and By-products for Construction of Highway Facilities. Federal Highway Administration, FHA, 34... 

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