To best comprehend Post-tensioning, it can be excellent to take into account the main difference between pre-stressed and reinforced concrete. Both reinforced and pre-stressed concretes make use of the structural capabilities of concrete and steel. Concrete is very strong in compression but quite weak in tension. Reinforced concrete beams supports loads towards the top but since it cannot resist the tension at the end, it easily cracks.
Steel bars in reinforcement are utilized to place in the tension zone to manage the cracking. Pre-stressed concrete entails the effective use of forces that have a tendency to bend and compress a concrete structure in counteractive bending that result from loading. The force applied will be the tensioning from the steel component in the look of wires, bars or high tensile strands. As being a typical practice, suppliers calibrate Stressing Equipments to complete post-tension installation successfully.
Multi Strand Jacks are being used in stressing all strands in unbonded tendons simultaneously. The main benefit of this is certainly its high-speed and precise stressing operation of the cables in just one trouble-free step.
Single Strand Mono Jacks are of three basic models; 10T mono jack is intended for that mining industry, and can be used overhead works. 17T mono jack is really a designated .5 strand in a lightweight steel model; it really is double acting and uses 3-piece reusable wedges. Lastly, the 25T mono jack that is capable of doing stressing 5mm wire up to 15.2mm strand with the easiness of exchanging two components with all the stokes of 6, 8, 12,18 and 24.
Grout Pumps are commonly employed for leveling concrete slabs, for filling cracks, for raising sunken concrete, sealing concrete holes, as well as for repairing tunnels, parking structures and bridges. The type of grout pump is dependant on the complexity in the job, either air-powered or manual according to what grout pump is essential.
Staple machines are no ordinary stapling machines. This can be utilized for attaching strands for prestressing concrete. Manually operated staple machines works extremely well in sites which are isolated sites to where high air pressure systems are certainly not accessible.
Onion Jacks are widely used to eliminate the application of anchor plates or wedges. It makes anchor point for prestressed tendons. The equipment forms an onion contour around the final of your cable by 61dexbpky of spreading and separating individual wires.
Swaging Jack is a type of Stressing Equipment that crushes or swages a barrel and wedge setting it on the end in the prestressing cable to create angle point. This jack is lightweight and power-driven by machine or a hand pump.
Inappropriate handling and good care of anchorage grip might occur to harm to property or perhaps physical injuries. Only qualified and well-trained personnel can operate the gear during use. Personnel doing the stressing plus the inspectors should always remain free from the tendons being stressed every one of the times. Jacks must be positioned on the strand to get stressed. It is far from better to adjust the positioning of the jack by striking or pushing after any load has become already applied. Do not rise above the intended capacities from the tendons or maybe the jacks being stressed, excess pressure might result to personal injury. To keep up jacks, it really is necessary to used only approved clean hydraulic fluid and alter it when needed. Jacks has to be cleaned immediately should it be subjected to air, rain as well as other corrosive environments after exposure. Usually do not stress any tendons which may have concrete slurry inside the anchor cavity, this will likely put off appropriate seating of the wedges.