Reinforced concrete slab

Roads and Walkways The cost of roads and walkways in chemical plants is difficult to estimate, since these vaiy with type of construction and thickness of applied cover. Some typical unit costs for roads are as follows For 305-mm (12-in) gravel base covered with 76-mm (3-in) asphalt, the cost is 17.10 per square meter ( 14.30 per square yard) for a reinforced concrete slab with a 152-mm (6-in) subbase, the cost is from 28.40 to 35.10 per square meter ( 23.80 to 29.30 per square yard), depending on the thickness of concrete (for M S = 1000). 

CBARCS, CUARCS - Optimum Nonlinear Dynamic Design of Reinforced Concrete Slabs Under Blast Loading, Program No. 713-F3-R0056, US Army Corps of Engineers, Waterways Experiment Station, Vicksburg, MS, 1980... 

Another important item is to consider how the finite element output data would be used to confirm compliance with acceptance criteria. For example, using stress output data from plate or shell elements to evaluate a reinforced concrete slab is not... 

Walls - Unreinforced masonry wall spanning between foundation and roof (one-way). Roof - One-way reinforced concrete slab. 

Mats. In designing foundations for some structures in low-load-bearing soils the combined area of spread footings approaches that of the supported structure. It is then more practical to use one large reinforced concrete slab or mat under the entire structure. In Fig. 8-3a typical mat construction for support of walls, columns, and flat-bottomed storage tanks is illustrated. A ventilated concrete mat and vertical support foundation for high-temperature supported structures is shown in Fig. 8-36. 

Flat-slab Floors. A flat-slab floor is a reinforced-concrete slab built monolithically and using a top-spread column support without the aid of beams and girders. In Fig. 8-16 the second and third floors are flat-slab construction. It is ideal for industrial buildings with live loads of 100 psf and square panel spans of IS to 30 ft, but the flooring must be... 

Kodur, V. K. and D. Baingo (eds) (1998). Fire Resistance of FRP Reinforced Concrete Slabs. IRC Internal Report No. 758. Ottawa, National Research Council of Canada. 

If the bearing capacity of the surface soil layer is not sufficient to allow for interaction with the piles, or if the embankment to be constructed is too high, concrete deck (or also known as piled raft) may be built on the ground surface on top of the piles. Concrete deck or piled raft supported on pile is expansive but will not be as expansive as a flyover structure. Alternatively geosynthetics such as geogrids can be laid on top of the pile cap. Figure 13.6 shows typical cross sections of the pile embankment, i.e. for the case of a pile with RC (reinforced concrete) slab as concrete deck, and piles with individual caps and geosynthetic fabric. 

In an unreinforced concrete slab, the contraction joints are spaced approximately every 4 to 5 m, depending on the slab thickness and type of aggregate. In a jointed reinforced concrete slab, contraction joints are typically spaced every 20 to 25 m, depending on the amount of reinforcement. The designer is advised to strictly follow the instructions of the pavement methodology used with regard to the spacing of the contraction joints. 

Separation membrane (except for continuously reinforced concrete slabs)... 

The amount of reinforcement required in reinforced concrete slabs is best determined by the formula or procedure given in the pavement design methodology adopted. 

Thickness determination of unreinforced and jointed reinforced concrete slab... 

As for jointed reinforced pavement, the thickness of the reinforced concrete slab is determined by the following equation ... 

A detailed procedure for designing rigid concrete pavements with jointed or continuously reinforced concrete slabs can be found in the AASHTO manual (AASHTO 1993). However, in the following paragraphs, a brief description for determining the thickness of the concrete slab in all cases (unreinforced or reinforced slabs) and the required quantity of reinforcement are given for the benefit of the reader. 

This technique is applied to unreinforced or jointed reinforced concrete slabs that show no major surface distresses. 

Missile barriers have frequently been provided in nuclear power plants to absorb the energy of postulated missiles and to prevent their travel beyond the barrier. Usually missile barriers consist of reinforced concrete slabs or of steel plates. However, other means such as woven steel mats or missile deflectors could also be used. Generally the barrier should be placed at the source of the missiles, as stated in para. 2.40. 

Figure 23.62 Pioneer Center, Nunhead, London. Reinforced concrete slab trimmed with cfrp reinforcement prior to cutting new opening. Courtesy Tony Gee.

A steel-conerete composite slab is newly available in construetion, of which concrete is placed in a steel mold that eonsists of steel side plates, top reinforcing bars and transverse ribs, and stud-planted bottom steel plates. Configuration of one t) e slab is shown Fig. 13.21. Compared with a reinforced concrete slab, this slab is expeeted to bear a large load- capacity and to have good enduranee. Although these eharacteristics are favorable for bridge construction, visual inspection is very difficult in particular, for concrete and its interfaee with steel plate. As a result, effective inspee-tion techniques for steel-concrete eomposite slabs are in demand and under development. 

Intermediate floors within the building and the roof are reinforced concrete slabs supported by structural steel beams. 

Simple symmetry of equipment is practiced. A single reinforced concrete slab is laid under the reactor building. Other engineered practices used are ... 

Generic Safety Issue (GSI) B-05 in NUREG-0933 (Reference 1), identifies two concerns relating to containment design. First, that sufficient information is not available to predict the behavior of two-way reinforced concrete slabs and second, that the structural design of a steel containment vessel subjected to unsymmetrical dynamic loadings may be governed by the instability of the shell. 

The first concern was originally identified in NUREG-0471 (Reference 2) and involved concern over the lack of information related to the behavior of two-way reinforced concrete slabs loaded dynamically in biaxial membrane tension (resulting from in-plane loads), flexure, and shear. If structures (concrete slabs) were to fail (floor collapse or wall collapse) due to loading caused by a... 

The acceptance criterion for Concern 1 is that analysis methods used for two-way reinforced concrete slabs adequately address dynamic loading in biaxial membrane tension, flexure, and shear that occur due to a HELB or LOCA. 

The Mark 11 primary containment consists of a steel dome head and either a post-tensioned concrete wall or reinforced concrete wall standing on a base mat of reinforced concrete. The inner surface of the containment is lined with a steel plate that acts as a leak-tight membrane. The dr3rwell, in the form of a frustum of a cone or a truncated cone, is located directly above the suppression pool. The suppression chamber is cylindrical and separated from the dr3rwell by a reinforced concrete slab. The drywell is topped by an elliptical steel dome called a dr3rwell head. The drywell inerted atmosphere is vented into... 

Rice, H,S. and L.Y. Bahar Reel ion—Time Relationship and Structural Design of Reinforced Concrete Slabs and Shells for Aircraft Impact. 3rd International Conference on SMIRT, Paper J 5/3 London (1975)... 

As an example, reinforced concrete slabs are prepared for an experiment to compare effectiveness of arc-sprayed zinc and titanium anodes. All the slabs will be put under impressed current cathodic protection, and exposed to controlled applications of chloride to the concrete to promote corrosion of the reinforcing bar. Slabs are assigned randomly to be coated with either arc-sprayed zinc or titanium. In this case, randomization is a desirable precaution to control small inconsistencies due to mixing of the concrete, the chemical composition of the concrete, or the distribution of aggregate in the concrete. 

The influence of steel fibres on the behaviour of high performance concrete slabs subjected to high velocity impact of projectiles was tested for construction of shields in military applications. The reinforced concrete slabs exhibited smash failnre, while the slabs reinforced with high volumes of fibres (7% and 10% volnme, pre-placed in the moulds) remained only with minor radial cracks on both sides. The projectiles were either embedded in or rebound from the targets. Several experiments were performed on slabs and plates subjected to perforation by projectiles or falling weights by Luo et al. 

Cheng, M.-Y., Parra-Montesinos, G. J. (2007) Punching shear resistance and deformation capacity of fiber reinforced concrete slab-column connections subjected to monotonic and reversed cyclic displacements, in International Workshop HPPRCC 5 in Mainz, RILEM, Proc. S3, W. H. Reinhardt and A. E. Naaman eds pp. 489-96. 

Where there are significant gaps in the floor slab (e.g. service entry points) the probability of failure would be 1.0. This is particularly relevant in block and beam slabs where the service entry points are often poorly sealed. It is less of an issue in large building with in situ reinforced concrete slabs with cast in service entries. 

The results of the probabilistic analysis of a cast-iron columns indicate that when a reinforced concrete slab is applied and material properties of columns updated by testing are considered then the reliability index P is around y 3.5 which is a little lower than the target value indicated in ISO 13822 (2010) for common types of structures in the consequence class CC2. In case the material properties recommended in the CSN 73 0038 (2014) need to be considered then the resulting reliability is very low(j8= 1.5 only). 

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