Service loads

Service load conditions are those loadings encountered during construction and in the normal operation of nuclear power facilities. A suggested summary of the list of loads is given below. 

Dead load is vertical load due to the weight of all permanent structural and non-structural components of a building, such as walls, floors, roofs and fixed service equipment as specified by the relevant codes and standards such as BS6399. 

Live load is the load superimposed by the used and occupancy of the building not including the wind load, earthquake load and impact load as specified by the relevant codes and standards. 

The live load is to be assumed in the design of building and other structures shall be the largest loads that can be expected to be produced by the intended use or occupancy, but in no case shall be less than the minimum uniformly distributed unit loads specified by the relevant codes and standards such as BS6399-1 to 3 or EC2, EC3. 

Floors shall be designed to support safely a concentrated load simultaneously with the floor live loads. In European codes it is termed as knife edge loads. 

---

Stresses may be applied and/or residual. Examples of applied stresses are those arising from thermal expansion and contraction, pressure, and service loads. Applied stresses may be continuous or intermittent. Examples of residual stresses are those arising from welding, fabrication, and installation. The importance of residual stresses in SCC should not be underestimated. Residual stresses may... 

Virtually all design parameters such as tolerances, material properties and service loads exhibit some statistical variability and uncertainty that influence the adequacy of the design. A key requirement in the probabilistic approach is detailed knowledge... 

When formulating a system for optimum abrasion resistance, both the epoxy/resin hardener binder system and the filler blends used appear to have an influence. The simulation of abrasive service loads on industrial floor toppings in a laboratory is not simple, and numerous wear test machines have been devised. Correlation between different wear test machines is not always good, although most... 

Develop practical test program to demonstrate components ability to meet structural and performance criteria. Extent of such test program, if any, depends on economic value of component, number of units to be produced, consequences of failure, accuracy of structural analysis and design, margins of safety used in design, knowledge about service loads and environments, and difficulty of duplicating service loads and conditions in test... 

TES-based systems are usually economically justifiable when the annualized capital and operating costs are less than those for primary generating equipment supplying the same service loads and periods. TES is often installed to reduce initial costs of other plant components and operating costs. Lower initial equipment costs are usually obtained when large durations occur between periods of energy demand. Secondary capital costs may also be lower for TES-based systems. For example, the electrical service equipment size can sometimes be reduced when energy demand is lowered. 

Concret does not have well defined elastic and plastic regions due to its brittle nature. A maximum compressive stress value is reached at relatively low strains and is maintained for small deformations until crushing occurs. The stress-strain relationship for concrete is a nonlinear curve. Thus, the elastic modulus varies continuously with strain. The secant modulus at service load is normally used to define a single value for the modulus of elasticity. This procedure is given in most concrete texts. Masonry lias a stress-strain diagram similar to concrete but is typically of lower compressive strength and modulus of elasticity. 

Stiff silty clay, allowable bearing (service load) = 2500 psf 2 ft (120 kPa 0.6 m) Safety Factor = 2 (for conventional loads from soil report)... 

Artillery projectiles may be classified according to use as service (loaded with explosive, chemical or leaflets filler) and training (loaded with inert filler or no filler at all)... 

Monitoring service loading and performance against performance capacity... 

Sometimes, there is not enough memory to load all the files for Card and Socket Services. In the DOS world, the software for Card and Socket Services loads in conventional memory (or in UMBs if you so choose). With many such DOS drivers being loaded, you may run out of conventional memory and not be able to run some DOS programs. 

There are a variety of methods for supporting the inner shell within the outer shell and the cold transfer line within the outer line. Materials that have a high strength to thermal conductivity ratio are selected for these supports. Design of these supports for the inner shell must allow for shipping loads which may be several orders higher than in-service loads. Compression supports such as legs or pads may be used, but tension supports are more common. These may take the form of cables, welded straps, threaded bars, or a combination of these to provide restraint of the inner shell in several directions. 

Note that the service stress in any loaded machine or structure is the algebraic sum of the applied stress, due to the service load, and any residual stress that may have existed before the service load was applied. If the residual stress is not known, neither is the service stress. When the service stress reaches dangerous levels, failure occurs. Interest in residual stress stems mainly from the role it plays in three kinds of metal failure fatigue failure, brittle fractures in general, and stress-corrosion cracking. 

Note also that the x-ray method measures the existing stress, whether it be solely residual or the sum of residual and applied. It therefore has the capability of measuring the actual service stress in a machine or structure under a service load. 

Figure 3. Generalized design diagram used for structural ceramics showing minimum failure time os. applied structural load. Each curve represents a differed ratio of the proof test load to the service load.

Mission profile Proper prescription of projected service loading and environmental conditions, with due consideration of variations in actual service experience. 

The most obvious requirement is that the deck should not collapse under a certain reasonable weight (load). What is a reasonable weight though The code specihes it as service load and employs a fail term rather than collapse. The ICC requirement... 

The composition of the products of tribochemical reactions depends on the service load and velocity regimes of the metal-polymer friction joint and the origin of the contacting materials. As has been indicated earlier, the... 

Such conventional-size tires have a standard aspect ratio of 80. The initial step in designing a tire is determination of the required size. Size determination is governed by rim dimensions, wheel well envelope, service load, service speed, and inflation. For a metric heavy-duty truck tire these factors are related... 

---