Water tanks are used to store water and are designed as crack free structures, to eliminate any leakage. In this paper design of two types of circular water tank resting on ground is presented. Both reinforced concrete (RC) and prestressed concrete (PSC) alternatives are considered in the design and are compared considering the total cost of the tank. These water tank are subjected to the same type of capacity and dimensions. As an objective function with the properties of tank that are tank capacity, width &length etc.
A computer program has been developed for solving numerical examples using the Indian std. Indian Standard Code 456-2000, IS-3370-I,II,III,IV & IS 1343-1980. The paper gives idea for safe design with minimum cost of the tank and give the designer the relationship curve between design variable thus design of tank can be more economical ,reliable and simple. The paper helps in understanding the design philosophy for the safe and economical design of water tank. What is stress corrosion of prestressing steel Stress corrosion cracking is a crystalline metals under tensile stresses in the presence of corrosive materials. Conditions of stress corrosion cracking occurs in the steel tensile stresses due to external loads or stress-induced internally (eg tendons). In addition, the presence of corrosive agents is essential to stress corrosion cracking start. A key feature is that the stress corrosion fracture of material with no damage observed from the outside. Therefore, stress corrosion cracking caused by the obvious warning signs.
The length of the steel work, if more than one wire or tape is the same, because all the cables / wires out at the same time?
If the child thread / individually highlighted in the same conduit, then these
stressed the wire / wire stand against the dull and the trap. Therefore, trapped in cable friction is high and is desirable.
What are the characteristics of the mortar inside the tendon ducts?
An oath is a pre serve the following purposes:(I) To protect the tendon against corrosion.
(Ii) improving the limited capacity of the tendon.
(Iii) the link between the structural and the tendon.
(Iv) In case of failure, the anchor is not subject to all the strain energy.
Because spalling confirmation is required for prestressing anchor is prevented?
Prestressed anchor blocks of work generally consists of balancing pop reinforcement reinforcement, reinforcement and erosion. Reinforcement of rupture is used when the tensile forces are induced during the operation of the preload and the maximum pressure occurs when the trajectories of the breakdown voltage are concave towards the line of action of the load. The reinforcement is needed to resist these lateral tensile forces. For the reinforcement of balance is necessary when there are several anchorages of prestressing loads are applied sequentially.
During the pre-load, the stresses generated in the chipping area behind the loading of the faces of the anchor blocks. In the area between two anchors, a volume surrounded by concrete compressive stress trajectories. The forces are induced in the opposite direction to the applied forces and forces the output of the concrete anchor. On the other hand, limitations of scale are in place thanks to the compatibility restriction on the effect of Poisson's ratio.
In such circumstances it is used by engineers to lift one end, and at both ends in the preload works?
During the operation of preload at one end, frictional losses occur and the prestressing force along the tendon decreases until it reaches the other end. These frictional losses include the friction due to a change of curvature of the tendon sheath and also wobble effect due to the difference in the alignment of the canal from the midline. Therefore, the prestressing force in the mid-range or at the other end will be significantly reduced in case of loss of friction is high. Therefore, the bias from both ends of a single span that is half preload tendon at one end, and the remaining half at the other end is made to ensure uniform distribution and to provide symmetry the prestressing force along the structure.
In fact, the stress at the other end is only possible to take advantage of low cost compared with the emphasis on both ends. Number of segments (for example, two blocks) and the irregular arc, lifting is usually done at the end of the longest period in order to obtain a position of force majeure claim the largest positive moment. On the contrary, hijacking the end of a shorter period would be, if the negative moment of the interim control preload on the force. If, however, the entire span is long enough to lift both ends should be considered.
What forces blood parasites? In isostatic structures, donors would be some concrete structures to fold up. Therefore precambering usually done to counteract this effect and make it more pleasing in appearance. But for the deformation of statically indeterminate structures of concrete members is hampered by restrictions, and the forces of parasites then developed by the leading force in addition to the bending moment generated by the eccentricity of tendons. The forces developed on the support modifies the response of concrete members subjected to external loads and produce secondary moments (or moments parasites) in the structure.
What are the major potential benefits in the form of use of precast girder bridge prestressed concrete slab above site? The potential benefits of using the bridge is prestressed precast beams supporting in situ concrete slab above are:
(I) For bridges built over rivers and roads, this form of bridge provides the platform for work by the precast beams so that construction of temporary structures is not necessary.
(Ii) that forms a bridge usually requires no cross beams or membranes (except for the location of the bridge supports), which reduces construction time and costs.
(Iii) It creates the potential for the simultaneous construction of taking several
Why kind of tension is better, preload preload internal or external? Different places the time interval (the third or fourth in points), the tendons are deviated from the correct profile of the concrete span preload external switches. Advantages of external prestressing are listed below:
(I) Due to the lack of connection between the tendon and its structure, exterior prestressing allows the removal and replacement of tendons or two at a time that the bridge could be adapted in case of damage and capacity could be increased easily. This is essential for bridges in urban areas where traffic problems is not desirable.
(Ii) it is usually easy access to anchor points and allows easy inspection.
(Iii) allows adjustment and control of the forces of the tendons.
(Iv) allows the designer more freedom in selecting the cross sectional shape of the bridges.
(V) web could be made thinner, so there is a reduction in dead load.
(Vi) is improved by reducing friction losses, as unintentionally as angular oscillation is eliminated. In addition, the use of polyethylene pipes external prestressing a coefficient of friction lower than the internal corrugated steel pipe prestressing.
(Vii) improvement of the concrete placement networks due to air channels.
A significant difference between the tendon internal and external post-tensioning steel is in the variation of eccentricity of the cable. Deflected shape of the external tendons is not exactly like the bars because of
moving the external tendons are controlled by evil. This is a second-order effect on the workload, and it is very important to the ultimate load.
Based on previous research, to include a small shallow (less than 3 m deep) with internal preload requires less steel reinforcement. However, deep cross section of the bridge, employment
Preload external results in a small amount of steel reinforcement.
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