Drilling Into Post Tension Slab

Unbonded Monostrand Anchor, Post Tension Anchor, Prestressed Anchor manufacturer / supplier in China, offering Unbonded Monostrand Post Tension Anchor, Cnm Full Hydraulic Crawler Anchoring Drilling Rig, Cnm 150 to 200m Hydraulic Crawler Drilling Rig and so on. Unbonded post-tensioning strands in slab areas to control temperature and shrinkage cracks, also in bottom of beams for load-carrying capacity. I went into a garage during an inspection yesterday. GPRS of Arizona received a call from a local mechanical company to mobilize and scan a concrete slab to mark out post tension cables and conduit within the slab prior to core drilling. On the other hand, the banded and distributed tendons limit the potential forms of the slab. Flat Slab Post-Tensioning of High-Rise Building in Las Vegas using the DYWIDAG Monostrand System: Trump International Condo/Hotel Tower, Las Vegas, NV, USA 78 GEWI® Tendons reinforce roof structures: Construction of a new exhibition hall for the Giovannelli plant farm, Pietrasanta (LU), Italy. tension load should be provided across the joint, and the joint should be roughened. This work code does not cover diamond grinding, joint sealing, or epoxy overlays. Post Tension Slab Although concrete is a strong material for construction, it is not resistant to breakdown especially where longer concrete slabs are required like in a bridge or a length of a beam. Remove and replace individual concrete slabs. 1R-07) outlines post-tensioning anchor stitching as desirable to strengthen the fractured area. Many post-tensioned slabs will be stamped to alert the owner and any renovation contractors that the slab is post tensioned. The document has moved here. Unfortunately, when the plumber was cutting holes for the new plumbing, he hit a pair of post-tension tendons. During construction care should be exercised not to drill or shoot pins into post-tensioned slabs where tendons may be located. sleeve, that you use a hammer drill and a sharp masonry bit to drill down into the concrete, you tap this in place. In typical post-tensioned building construction in North America, the vertical elements (reinforced concrete columns and shear walls) and slab on ground are typically constructed with reinforced concrete, while the elevated horizontal elements (slabs and beams) are typically post- tensioned. Perimeter Treatment - The most common termite treatment which involves drilling attached slabs including the garage as well as trenching the soil along the foundation. The compost action is obtained by the application of studs on steel beams that extend into the slab voids that filled with hydraulic cement or polymer in later times. What does slab on grade mean? Information and translations of slab on grade in the most comprehensive dictionary definitions resource on the web. anchors can be post-tensioned off to limit upward movements; in this case, the top of the micropile is designed to be “unbonded” and the threadbar extends through the footing, grade beam or mat so that it can be tensioned and locked off to a specified load. At Vector Structural we provide responsible core drilling crews that understand structural concrete, thus minimising the risks associated with core drilling. A tendon-identifying, post-tensioned, elevated concrete slab, and method and form panel apparatus for constructing the same, provides a distinctively-patterned bottom side slab surface in which the slab has a full thickness dimension extending along each individual post-tensioning uniform and banded tendon embedded within the slab and a reduced-thickness dimension in the areas between each. Post-tensioning is often the desirable solution when a major portion of a member must be strengthened or when the cracks that have formed must be closed (Fig. Several methods exist for pre-stressing concrete, with post-tensioning being a very common one. Advantages of Post-Tensioned Slabs over conventional RCC slab: Among the advantages of this systems over unbounded Post - Tensioning are: Large reduction in traditional reinforcement requirements as tendons cannot distress in accidents. The best practice today is to make them as long as possible, terminating them in the concrete mat under the concrete foundation. An exchange for safety professionals on solving their safety issues. Bonded prestressing strand in the lower half of the double-tee stems, beams, and lobby or roof slabs only. Ditto for saw cutting of the slab, as another poster mentioned. If post-tensioning could be eliminated, the speed of installation could be improved. Introduction. Tendons can be easily “woven” allowing a more efficient design approach. ALIGN UPPER ARM OF POST W/REAR. I'll have 2 24 gun safes and I want to secure them to the concrete floor. From time to time even the post tension slab could crack or allow entry point for termites to get through, the floating slab has concrete meeting concrete and therefore has a crack where termites can make entry into the home. Optional casters enable you to move the lift or even roll the unit outside to wherever best suits your needs. Floor slab supported by beams is a major part of the horizontal stiffening member in framed structure. Demolition From selective demolition to cutting slabs and walls, we will effectively demo to your specifications. Once the base is in place, the bottom of the post slips right in. Each segment was set onto three screw jacks to be positioned and aligned with the previous match-cast piece. The only concern is to always remember not to cut or drill into post-tensioned concrete slabs, since once a tendon has been cut, it is very difficult to repair. Sugimura, Director for the use of post-tensioned concrete slabs and be no drilling into the. The bars may be equipped with hooks or heads on the cast-in end, but are by necessity straight on the post-installed end; b. Structural engineers and contractors in San Diego, Orange, and Los Angeles counties use post tension cables in residential concrete slabs to offset the effects of expansive soil conditions that exist in most of southern California. Ground Penetrating Radar is an excellent tool for locating buried pipe. Now that being said, you still need to take precautions, but post tension slabs are usually 10"+ thick. You core drill these holes. With newer multi-residential wood frame structure being built on podium slabs and using post tension concrete, drill and epoxy is not a favorable option because of the potential of drilling into a tension cable. We’re currently discussing options for concrete sport courts with a client. Many post-tensioned slabs will be stamped to alert the owner and any renovation contractors that the slab is post tensioned. Post-tension structures and/or structures with a significant amount of rebar also present an obstacle. 13—Post-tensioned tendon anchorage zones 18. In unbonded post tension concrete flat plate slab - Multi story building, in case MEP installation were a drill used in concrete slab make a penetration in bottom more than 3/4" (the min concrete. Post Tension Slabs versus Floating Slabs. Specimen CB2 drilling geometry and strands profile. The possibility of compounding scheduling delays will occur since certain tasks have to be completed before others can take place. It should be kept in mind that no cutting or drilling should be done to post-tensioned concrete slabs, because once a tendon is cut, it becomes complicated to repair. Now that being said, you still need to take precautions, but post tension slabs are usually 10"+ thick. What is Post-Tensioning: Post tensioning is a technique for reinforcing concrete. ASTM International is an open forum for the development of high-quality, market-relevant technical standards for materials, products, systems, and services used around the globe. In the course of DSI's long-time successful activities, DSI Canada has concentrated on the Geotechnical and Post-Tensioning fields and gained a position as the leading specialist for demanding Geotechnical and Post-Tensioning Systems. Any one know what I'm looking at here? Thank you. 7) Requirements for re-vibration. without the requirement for drilling of the slabs. One of these modifications was relocating some plumbing. The top slabs of the segments were transversely post-tensioned in the casting yard with two. So we dug into it and got some installed numbers. With fabrication facilities across the Nation, Suncoast has the resources to supply projects, small to large. While primary framing had been done for some time, he was wrapping up some modifications to the ground floor (a post-tension podium slab). The use of external post-tensioning for new structural systems have been developed in the past decade. Florida Foundation Repair We Will Put Your Foundation Back On Solid Ground – Guaranteed! “We found a crack on our foundation…Foundation Services owners, engineers, crews and staff worked as a team…competent, courteous and diligent…a true interest in our concerns…efficient and very neat…they relieved anxiety on our part…excellent work…we feel we were blessed to have Foundation. tension load should be provided across the joint, and the joint should be roughened. The structure consisted of precast units stressed together both lon­ gitudinally and transversely. Openings may be large, such as those required for a new stairway, or small core penetrations, such as those required for plumbing risers. The other end has a Push-Lock Fitting which requires no swagging or special tools. Contractors sometimes need to drill or cut into a post-tensioned slab for repair or renovation work. All slabs are designed with a 28-day compressive strength (f’c) of. Post-tensioned concrete means that the concrete is poured and then the tension is applied-but it is still stressed before the loads are applied so it is still prestressed. •Balance loads reduce the load on the columns and foundations. An approach slab thickness of 20 in. In the course of DSI's long-time successful activities, DSI Canada has concentrated on the Geotechnical and Post-Tensioning fields and gained a position as the leading specialist for demanding Geotechnical and Post-Tensioning Systems. MODULE 3 - BREACHING-BREAKING-CUTTING- BURNING SM 3 3 Types of concrete nPeople often misuse the word cement and concrete. How does the Hilti PS1000 work? The PS1000 uses ground penetrating radar (GPR) to image targets that are different than the concrete being scanned. Grind and polish your axle to get a nice needle point - it must be perfectly centered!I prefer to do this with the axle in a fast spinning drill on a fine grinder. Large penetrations for new stairs, elevators or air conditioning ducts will require an analysis of the floor system by an engineer, regardless of whether the floor is post-tensioned or not. The only concern is to always remember not to cut or drill into post-tensioned concrete slabs, since once a tendon has been cut, it is very difficult to repair. I wouldn't drill anything without someone's approval first. The Macalloy Post-Tension bar provides an ultimate yield strength of 1030 N/mm2. Surfaces can be stained or overlaid. Drilling into a post-tensioned slab Another popular myth with post-tensioned slabs is that it is very difficult to drill into an existing slab because of the unknown location of the tendons and anchors. Joint sealant At precast-to-precast joints and pour strip tooled joints. These are very common in high-rise construction in the last 20 years or so, because they allow for flat slabs (simplifying formwork and saving $$) and shallower slabs (allowing the developer to fit more units in the same height. •Post-Tensioned concrete is crack free. embedments such as existing steel reinforcement, utility ducts and post tensioning hardware. of reinforcing slabs again st shear failure h ave bee n developed. The Macalloy Post-Tension bar is available in diameters from 20mm Shear Connectors SRG Global offer a range of permanent movement shear connectors for both slab on grade. External post-tensioning. The bond between the post-tensioned CFRP plates and the downstand beam was achieved using Sikadur®-30 adhesive. The Fas-N-Fast Newel Mounting System is perfect for installing our solid wood newel posts, specifically for use with Cable Railing Systems. Provide labor, materials, necessary equipment and services to complete the post-tensioned concrete work, as indicated on the drawings and as specified. Floor Slab Cores at Column Capital. I'll have 2 24 gun safes and I want to secure them to the concrete floor. Section 03450 “Architectural Precast Concrete. Aug 29, 2012- Concrete foundations, retaining walls, structural concrete, helix piers by concrete contractors in the Santa Cruz Construction Guild. This page is your post tensioning one-stop source for the competitive prices and quality from sewing machine suppliers and manufacturers. 13' thick slab? I assume you mean 13", a perimeter beam could be 13' deep. Such anchors typically comprise tendons of high-tensile bundled steel strands or individual threaded bars. Suncoast offers a wide array of commercial, industrial and residential concrete services spanning from concrete curb cutting, diesel flat sawing, electric flat sawing and core drilling to the latest technology in scanning, 3D imaging and Ferro scanning. Grouting and Injection are important components of the modern era concrete construction industry. Special Inspections Checklist 2012 NC Building Code Section 1704 (check all boxes that apply) Page 4 of 7 Periodic Continuous Verification of in-situ concrete strength, prior to stressing of tendons in posttensioned concrete and prior to removal of shores and forms from beams and structural slabs. Marking Tendon Positions Post-tensioning strands are made from hard steel so it is difficult to damage them with a Tungsten Carbide (Masonry) drill bit if care is taken. Safe and fast: Flat Slab Post-Tensioning at the AQ 01 Gateway Tower at Abraj Quarter on The Pearl. But as long the tendons and the concrete in front of the anchors are not damaged, drilling into a post-tensioned slab is a fairly routine issue. Brittle fracture A sudden failure of a steel element in tension. Looking for post tensioning? You’ve come to the right place. Avoid hitting post tension cables before drilling into a post tension slab. It was built in 1953 and collapsed. The best way to determine post tension depth and cable location is with the latest ground penetrating radar (GPR) technology. WiseRail™ Legacy Cable Railing - Inside Run for Wood Posts has an Adjust-A-Body with hanger bolt tensioner allowing you to penetrate the screw directly into the inside of your wooden end post. This produces a smoother ride for forklifts. Heslin1, D. Our advanced hi-resolutionGPR systems can “see” those conduits, post-tension cables, rebar and mesh. The area immediately behind the anchorage should be free of sleeves, blockouts, large conduits, or other voids or congestion that could cause the concrete to fail in this high-stress zone. Back in the 1960 there was limited use in concrete foundations in residential construction, but very little. The impossibility comes from the unknown location of the tendons and anchors. Any idea how to drill through the back of a safe to secure it to the wall? I'm not talking about the $500 "safes" from Academy. Post-Tensioning bar systems are high strength bar systems with superior fatigue properties. There was also a city inspection sign off sheet next to this sign. GPR is completely safe and approved by the FCC. Post Tension Footing ? You mean Post Tention Slab, correct ? If you have PTS in your house, you should only score the slab and carefully break the slab avoiding buried cables. Once the base is in place, the bottom of the post slips right in. Strengthening of structures with post-tensioned CFRP plates ®-CarboStress is a system for strengthening by the post-tensioning of carbon fiber reinforced plastic (CFRP) plates. All openings are to be constructed by a contractor who is approved by the Manager of Construction Services. The Village at SouthPark Bulletin 2 Post Tension Slabs No Tenant, Tenant Contractor or Subcontractor is to attempt any drilling or core boring of the base building post tension slab structures. borescope—a device composed of a rigid or flexible tube with mirrors and lenses that is inserted into a small drill hole or other access channel to provide a visual image of internal conditions. In most post-tensioned residential buildings, there is a fair amount of coordination between the post-tensioning (PT) contractor and MEP trades. Steel plate bonding is a cumbersome process requiring extensive hacking & drilling in the existing section. Both rock and soil anchors are tensioned to the required force using an accurately calibrated hydraulic jack. The best way to determine post tension depth and cable location is with the latest ground penetrating radar (GPR) technology. In most post-tensioned residential buildings, there is a fair amount of coordination between the post-tensioning (PT) contractor and MEP trades. We have been receiving a large volume of requests from your network. supporting post tensioned structures after stressing the post tensioning tendons as described in the specifications and shown on the plans. The depth of the pilot hole should be approximately ¼-inch greater than the length of the masonry screw. The two options are a cast in place concrete slab or a post tensioned slab. City of Seattle Department of Planning and Development Diane M. walls of tanks fixed in the bottom slabs or post-tensioned slabs of vehicle scales, the tendons have been used in extremely thin floor slabs. I really do not want to be drilling into the concrete and risk hitting one of those cables, so what other options do I have?. Post tensioned special inspections (PTSI) were undertaken on numerous structures in the UK during the latter part of the 20 th century as a result of a number of catastrophic failures in structures world wide. To correct cracking of a beam or slab the American Concrete Institute (ACI 224. It keeps the structural integrity of surrounding areas intact. Florida Foundation Repair We Will Put Your Foundation Back On Solid Ground – Guaranteed! “We found a crack on our foundation…Foundation Services owners, engineers, crews and staff worked as a team…competent, courteous and diligent…a true interest in our concerns…efficient and very neat…they relieved anxiety on our part…excellent work…we feel we were blessed to have Foundation. slab and carried it into place on top of the underslung equipment. HAVEN can work on a variety of different floor types. Post Tension Footing ? You mean Post Tention Slab, correct ? If you have PTS in your house, you should only score the slab and carefully break the slab avoiding buried cables. can complete concrete inspections where we draft and produce as build documents detailing the depth, diameter, and dimensions of any embedded post tensioned system. drill & epoxy n20-300 starter bars central into bored pile 600mm into beam top and bottom. This is extremely dangerous. This page is your post tension one-stop source for the competitive prices and quality from sewing machine suppliers and manufacturers. 75-100 mm from soff saw-cut (both sides) Max. The glossary is a. Hi guys, in the next few weeks I'll be starting construction on my new house. The polishing in a simlilar way, but please do not try it with a cloth in your hand on a spinning axle!2. bored pile capping beam refer typical details. Drilling into a post-tensioned slab Another popular myth with post-tensioned slabs is that it is very difficult to drill into an existing slab because of the unknown location of the tendons and anchors. Deck removal and replacement projects can currently be completed in as little as two days. Perpendicular to the tendons, the banded tendons run with the columns. International expansion Concessions First proposal Entry into the Post-tensioning business Constitution of the company Constitution of the company Echeverria. 1 Definition of rebar Reinforcement anchorages or splices that are fixed into already cured concrete by Hilti HIT injection adhesives in drilled holes are called "Post-installed rebar connections" as opposed to normal, so called "cast-in" reinforcement. Penetrations into Floor Slabs for Fasteners. I'm not a fan of PT slabs at all. This will leave no visible fixings and will look like the post is set into the concrete. Although roughening of the slab surface improves adhesion and is advisable to improve. Other facets within the industry we do include specialty installation of post-tensioning cables. One or more such structures are also post-tensioned using cables passing through tube embedded in the cast concrete structure and, when a plurality of such structures are employed in a modular manner, such post-tensioning draws all such modules into a larger unitary composite wall foundation and floor slab structure. REAL BENEFITS Post-Tensioned Slabs 2 10. The best way to determine post tension depth and cable location is with the latest ground penetrating radar (GPR) technology. Less likely to hit reinforcing steel or post-tension cable in concrete n No wasted time or energy drilling deeper than necessary n Prevents anchor from dropping too far into. If SockFix assembly is over 1000mm (36”) in length it should be wet again once inserted. : 25 The tendons are not placed in direct contact with the concrete, but are encapsulated within a protective sleeve or duct which is either cast into the concrete structure or placed adjacent to it. Ground anchors are effectively restraining devices used in many different types of structures including retaining walls, dams, wharves, bridge abutments and foundations for buildings. One of the most economical slab edge details incorporates a 10- to 20-gauge cold-formed metal pour stop (edge form) welded to the spandrel beam in the field, during erection of the metal deck (Fig. Post-tension and pre-tensioned (PT) cables are commonly used in concrete construction to facilitate thinner slabs and greater span lengths between support columns. The cost of such mistakes can be prohibitive. He's talking post tensioned not pre tensioned. The drills robobore and the like use are water cooled and are about £500. Post tension slab is the foundation of choice around Texas with the exception of few enclaves and the older homes. Therefore, GTI is making available our glossary of post-tensioning terms. The only concern is to always remember not to cut or drill into post-tensioned concrete slabs, since once a tendon has been cut, it is very difficult to repair. Many post-tensioned slabs are often stamped to alert workers, as well as owners, in case any renovations take place in the future. curred in 1968 when a full scale post-ten-sioned slab was built and tested to destruc-tion. This will provide you with a non-invasive, cost-effective, and safe working environment and allow you to proceed with confidence in your cutting and drilling endeavors. Rehabilitation of the I-81 Bridges over Oneida Lake & Erie Canal Sam Anthony P. A tendon will have anchors on each end to transmit the forces into the structure. Does the slab contain post-tension cable? If so, this must be located first. Other factors affecting the decision to drill are the risk of hitting rebar or post-tensioning components. Comparing a house slab to a manufactured product doesn't take into account that the mix and materials used are different, or that the amount of water added to those mixes is carefully, and religiously controlled. The core drill before will do it (in a few weeks)!, concrete of this application is very hard. Cast-in-place anchors are the best solution for most. This project was nominated for the ASCE/FES Ridge Branch project of the year award in. The impossibility comes from the unknown location of the tendons and anchors. Kiner, Ohio Department of Transportation District 6 Rich Street Bridge Project The Scioto River gets a ribbon for Columbus’s 200th birthday The Rich Street Bridge was the perfect back-drop to Columbus’s famed Red, White, and Boom Fourth of July celebration. Perimeter Treatment - The most common termite treatment which involves drilling attached slabs including the garage as well as trenching the soil along the foundation. GLOSSARY OF POST-TENSIONING TERMS By Larry B. I confirmed with the builder it's a post tension slab. Post-Tensioned concrete was originally developed during the 1930's by a Frenchman, Eugene Freyssinet, who realized that placing concrete under compression greatly increased its strength. This work code does not cover diamond grinding, joint sealing, or epoxy overlays. After the concrete has cure per the engineering requirements, the cables will be tensioned and excess cable ends will be cut off. Flat Slab Post-Tensioning of High-Rise Building in Las Vegas using the DYWIDAG Monostrand System: Trump International Condo/Hotel Tower, Las Vegas, NV, USA 78 GEWI® Tendons reinforce roof structures: Construction of a new exhibition hall for the Giovannelli plant farm, Pietrasanta (LU), Italy. We have been receiving a large volume of requests from your network. My house has them & the plans indicate they are tensioned to 18,000 pounds. They have a number of outstanding advantages. feet of existing concrete, excavating 1100 cubic feet of the dirt below the slab prior to installation of the conduit, new steel, post-tensioned cables that will be in the new training area. There was also a city inspection sign off sheet next to this sign. The building had a glass and masonry veneer precast panel exterior envelope. GPR can accurately locate PT cables in concrete slab and even in a slab on grade. It consists of Anchor, Casting, Wedge and Bursting Reinforcement. Floor Slab Cores at Column Capital. Once a tendon has been cut, it is very difficult to repair. Located in the eastern and also in the western part of Canada, DSI can serve its customers all over Canada. But as long the tendons and the concrete in front of the anchors are not damaged, drilling into a post-tensioned slab is a fairly routine issue. Ground Penetrating Radar is able to map the path of subsurface piping and determine the approximate depth to the top of the pipe. Post Tension Slab Although concrete is a strong material for construction, it is not resistant to breakdown especially where longer concrete slabs are required like in a bridge or a length of a beam. Ideally, the installation screws will be drilled at least one inch into the subfloor. Even in the case of post tensioned slabs, a minimum of #3 reinforcing steel bars, at a spacing of 12" on center, should be utilized by drilling into the existing slab horizontally and epoxying the reinforcing steel bars to provide integrity. Making contact with post-tension tendons when drilling holes can cause catastrophic failure of overhead concrete panels. Perpendicular to the tendons, the banded tendons run with the columns. SDS-Plus Masonry 1 Piece. Only ICC approved structural thermal break – ICC-ES ESR 3799; All standard units come with 2 HR fire rating. Existing tendons can be located simply by the use of a pacometer (hand held metal. Once the slab cures, qualified personnel apply tension and grout the cables. Careless drilling through a concrete slab could result in injuries as well serious degradation of structural strength of the slab. GLOSSARY OF POST-TENSIONING TERMS By Larry B. Performance of HDPE Duct 1. The slab is now ready to be poured. This drilling CANNOT be done on a post tension slab. Very effective in limited spaces. To obtain maximum benefit from CCL Post-Tensioned Slabs it is recommended that they are incorporated. As with any repair, the extent and cause must be identified and addressed. Our certified concrete scanning technicians can help a coring crew navigate through a slab without damaging any structural elements such as conduit, rebar, or Post-Tensioned cables. DYWIDAG Strand Anchors. I went into a garage during an inspection yesterday. You drill into the concrete and insert concrete screws or anchors. Sorry for the interruption. The high movement joint is suitable for the expected large gaps associated with PT slabs. Rebar Locate - Park City, Utah Ground Penetrating Radar Systems was contacted by a general contractor to locate all of the rebar in multiple locations of a suspended slab. That said, the cost of drilling, along with the price of post-installed anchors, can make this method unappealing for larger projects. What would happen of you cut one of the cables in a post tensioned floor in a building? I am an electrician by trade and I do a lot of core drilling to penetrate floors between levels in a building. Slab depressions. To minimise. Concrete is a material with incredible compressive strength but limited tensile strength. As a structural element, the PT tendons/anchors take precedence over MEP sleeves, openings/penetrations, embeds and even rebar. Post-installed reinforcing bars are embedded in adhesive in a hole drilled in existing concrete on one side of the interface and are usually cast into new concrete on the other side of the interface (Figure 1). Many post-tensioned slabs will be stamped to alert the owner and any renovation contractors that the slab is post tensioned. The tradeoff for smaller diameter is a decrease in pressure tolerances. Your post was unclear if the holes were in the slab on grade or supported slab. If someone gave me a rotohammer on a post tension slab I would leave. This location is typically congested with tendons near the top of the slab and shooting pins may cause damage to.   Post tension cables are laid out in both directions. Post Tensioned Slabs Plate 60 ArmourMate™ is designed to be used on post tensioned (PT) slab projects. Generally, there are six main drilling techniques and their principles and range of application. The effect is a spring-loaded slab that is resistant to any movement and most cracks. 15—Design of anchorage zones for multistrand tendons 18. In today's engineering practices post tensioning is a critical element that defines the structural capabilities of concrete slabs, concrete decks, and concrete bridges. The glossary is a. Post-Tensioning bar systems are high strength bar systems with superior fatigue properties. The emphasis of the article is on repair and reinforcement options, including the use of scarf repairs, stainless steel flitch plates and the use of resins. MODULE 3 - BREACHING-BREAKING-CUTTING- BURNING SM 3 3 Types of concrete nPeople often misuse the word cement and concrete. There was also a city inspection sign off sheet next to this sign. , which form the concrete frame and structure including items to be post-tensioned Slabs. I can't remember how much tension those cables are under but I remember vividly what happens when they fail. The only concern is to always remember not to cut or drill into post-tensioned concrete slabs, since once a tendon has been cut, it is very difficult to repair. 1 SUMMARY A. Donald Illingworth Û A pioneer in post-tensioning slab-on-ground foundations, Illingworth was introduced to post-tensioning in 1971 while employed by Atlas Prestressing. (Overhead installations need not be blown clean. If you hit an especially hard piece of concrete, insert a masonry nail into the hole and hammer it in to break up the concrete. Tendon Repair: The most important thing to remember with a post-tensioned structure is not to cut or drill into a beam or slab with these tendons. This is extremely dangerous. In the case of pre-tensioned and post-tensioned concrete, the stress is maintained by a large nut on the end of the steel strands, whichi is embedded in the concrete, and forms a permanent connection. Concrete Services. Post Tension Slab (Cut Cable) My plumber hired a post-tension cable repair contractor who replaced one half of the cable, used a special coupling at the cut point to secure the new and old. Commonly used by plumbers and electricians to install conduit from one level of a residence or building into another below. Together, they cited information from 18 references. Strengthening system using post-tension tendon with an internal anchorage of concrete members Tatsuhiko Mimotoa,b, Takuya Sakakia, Takafumi Miharab, Isamu Yoshitakea,⇑ a Department of Civil and Environmental Engineering, Yamaguchi University, 2-16-1 Tokiwadai, Ube, Yamaguchi 755-8611, Japan. Once you have laid out the strands then you can. The idea behind post-tensioning is to balance or counteract a certain portion of the load imposed on the structure. We are doing scored and stained concrete so there is no issue with wood, tile, carpet, etc there. A slab scan helps to minimise risk and maximise the safety of structures, services and workers, this is our speciality. Concrete Scanning with Ground Penetrating Radar Technology With new build construction and renovation projects, the likelihood of needing to cut or core a concrete slab is high. The Project. Typical post- tension beams (ribs) are 12 inches wide versus 16 inches wide for conventional. Sand cushion was provided on the lower slab to minimize damage to the slab due to falling debris. Post Tension Slab Although concrete is a strong material for construction, it is not resistant to breakdown especially where longer concrete slabs are required like in a bridge or a length of a beam. I have built many 20 or so story condos in Florida with post tension cables. The concrete is then poured and left to reach sufficient strength then tension is applied to the strands by using a hydraulic jack at the live end. Donald Illingworth Û A pioneer in post-tensioning slab-on-ground foundations, Illingworth was introduced to post-tensioning in 1971 while employed by Atlas Prestressing. refer to typical slab to bored pier details. In general, as long the tendons and the concrete in front of the anchors are not damaged, drilling into a post-tensioned slab is a fairly routine issue. With new build construction and renovation projects, the likelihood of needing to cut or core a concrete slab is high. Other facets within the industry we do include specialty installation of post-tensioning cables. Although roughening of the slab surface improves adhesion and is advisable to improve. The possibility of compounding scheduling delays will occur since certain tasks have to be completed before others can take place. You have to have an engineer tell you where you can drill though. Any idea how to drill through the back of a safe to secure it to the wall? I'm not talking about the $500 "safes" from Academy. Post tension slabs must be marked or stamped with an identifier placard, as they cannot be drilled or cut into by a lay-person. diaphragms; even where this is not the case, the amount of reinforcement present makes drilling inadvisable. If the drywall is directly onto the concrete, drill into the concrete and use a shield and screw or there is a concrete screw called Tapcon that screws directly into the concrete without a shield. Contractors sometimes need to drill or cut into a post-tensioned slab for repair or renovation work. Before any cutting, sawing or drilling ensues, scanning concrete with such a tool a GPR can help determine the location of steel reinforcement, post-tensioning cables, electrical cables and conduits, etc. This can help to minimize cracking and differential settlement in adverse conditions. Movable and fixed anchors are. VSL post-tensioning systems utilized for this project include 5-19 longitudinal tendons as well as 6-4 transverse tendons. Apply epoxy into the reamed out cavity with a 2" paintbrush. This is expensive but reliable, (about $500. The document has moved here. The core drill before will do it (in a few weeks)!, concrete of this application is very hard. Hopper, and Carol Hayek D esigned by Maki and Associates and architect of record Gensler, the 185,000 ft2 (17,190 m2) Novartis Oncology Research Building reflects the fast-paced. post-tensioning tendons to remain. In 1965 the writer developed a complete, overall design system, later modified to con-. Post-tensioning Shrinkage-compensating concrete puts slabs into compression using chemical action. With nine plants from coast to coast. The journal welcomes submissions across a range of disciplines, and publishes both theoretical and practical studies. Other factors affecting the decision to drill are the risk of hitting rebar or post-tensioning components. Less likely to hit reinforcing steel or post-tension cable in concrete n No wasted time or energy drilling deeper than necessary n Prevents anchor from dropping too far into. The floor system for the Granby Tower consists of a two-way flat plate post tensioned slab designed in accordance with the 6th Edition Post-Tensioning Manual by the Post-Tensioning Institute and ACI 318-02. Whether it's for new or existing builds, from residential buildings to bridges, Hilti have a solution. DCX-138 3/8" Depth Charge Stop Drill 3/4" DCX-112 1/2" Depth Charge Stop Drill 1" Multi-Set II Depth Charge Bits SELECTION CHART n Shoulder prevents over drilling. Post-tensioned Concrete Floors PAGE ii Contents Development of Post-tensioned Floors Principles of Post-tensioned Floors Introduction In the UK, the use of post-tensioned (PT) concrete floors. My current shower is a prefabricated fiberglass unit. Post-tension structures and/or structures with a significant amount of rebar also present an obstacle when drilling. Provide labor, materials, necessary equipment and services to complete the post-tensioned concrete work, as indicated on the drawings and as specified. HOW TO USE POST-INSTALLED REBAR. ASCE, Erdman Anthony, Rochester, NY. Post-installed reinforcing bars are embedded in adhesive in a hole drilled in existing concrete on one side of the interface and are usually cast into new concrete on the other side of the interface (Figure 1). Located in the eastern and also in the western part of Canada, DSI can serve its customers all over Canada. Penhall Technologies scanned a condo unit to locate post tension cables at multiple locations prior to drilling into the ceiling. This can help to minimize cracking and differential settlement in adverse conditions. If you have one of these slabs, it should be marked "Post Tensioned Slab, Do Not Drill Cut or Core. All threaded inserts shall be Dayton Superior F-62 Flared Thin Slab Ferrule NC threaded insert or an approved equal having a minimum mechanical ultimate tensile strength of 8000 lbs. This is expensive but reliable, (about $500. The only concern is to always remember not to cut or drill into post-tensioned concrete slabs, since once a tendon has been cut, it is very difficult to repair. and, at times, their depths may vary. •Post-Tensioned concrete is crack free. Because of the brittle nature of shear failures, conservative design is necessary. Post-tensioning reinforced concrete floors have become an important factor for all types of commercial and residential projects, and floor systems. Stress Anchors (also commonly known as Live Anchors) is the most widely used form of anchors in prestressed concrete works. Experts please help. When drilling into PT slab, prevents user from drilling into post tension cable. Once the geometry of the bridge falsework has been obtained, prefabricated spacer frames are set into place. The reason for the warning sign is to alert the owner not to cut or drill into the concrete without having a professional contractor do the cutting or drilling – it’s a safety thing, because if one cuts a post tension cable, it may whip upward and injure the person. Post Tension Cable Location. But before you decide whether to use rebar or post-tensioning, I think you could benefit from knowing how the two systems work.