Construction joint

Leaks in various Periodic replacement of components system compo-. pressure test all lines nents, hoses, valves swivel insure proper materials of construction joints in arm, lance, etc. CCPS G-3 CCPS G-22 CCPS G-29... 

Source From AFS, Alternative Utilization of Foundry Waste Sand, final report (Phase I) for Illinois Department of Commerce and Community Affairs, American Foundrymen s Society, Des Plaines, IL, July 1991. Javed, S. and Lovell, C.W., Use of Foundry Sand in Highway Construction, Joint Highway Research Project No. C-36-50 N, Purdue University, West Lafayette, IN, July 1994. Javed, S., Lovell, C. W., and Wood, L.E., Waste Foundry Sand in Asphalt Concrete, in Transportation Research Record, No 1437, Transportation Research Board, Washington, DC, 1994. 

Javed, S. and Lovell, C.W., Use of Foundry Sand in Highway Construction, Joint Highway Research Project No. C-36-50N, Purdue University, West Lafayette, IN, July 1994. 

The response will be limited to the clastic range even though cracking will probably be caused by out-of-ptanc bending and by the construction joint at the base of the wail. Such pre-cracking is not reliable enough for a design basis unless special construction details are provided to ensure behavoir. 

If a pour is to be halted either by operational problems or by design, the last layer placed before the interruption can be further retarded by the use of larger dosages of the admixture. This can eliminate the necessity for construction joints. The heavily retarded concrete can be horizontal in the placing of layers or vertical when a sloping layer of concrete should be left. 

In large pours where construction joints can be reduced thus speeding up construction. 

To check for construction joint leakage, scan all joint areas from a distance of 6 in. at a speed of approximately 10 in./min. 

No construction joint leaks or intrusion through open doors should exceed 0.1% of the measured external concentration. See Tables 6 and 7. 

Underground tunnel construction joints and sections Attaching metal studs in concrete Bonding pancake lighting systems on airport runways Bonding traffic markers on roadways and road dividers... 

S-I loop is being constructed jointly by Commissariat a I Energie Atomique (CEA Section I), Sandia National Laboratory (SNL Section 11) and General Atomics (GA Section III). The three sections will be integrated for a bench-scale demonstration capable of delivering 200 to 1,000 1/h of H2 in 2008. °... 

Oil and solvent related environments Building and construction joints... 

Whereas epoxy crack injecting systems are applied in static cracks, polyurethane systems are suitable for cracks where some movement is anticipated. There are other applications where polymeric materials are considered as competitors to each other. For example, neutral cure silicone sealants and polyurethane sealants are both suitable for use in construction joints. The former type offers greater durability and ageing resistance. However, polyurethane sealants are widely used because of their cost-effectiveness. Furthermore, some products are preferred over their counterparts for environmental reasons. 

Sealants, for construction joints retention of movement capability high tear strength good recovery weathering resistance range of colours... 

Self-levelling polyurethane sealants are used to seal horizontal movement joints and construction joints in a variety of materials subject to light traffic such as concrete pavements (Figure 4.4), access roads, yards, parking areas, between rails and metal enclosures and around equipment and machinery. 

Silylated urethane polymers allow formulators to produce fast-cure construction joint sealants with superior performance properties. The sealant is composed of silylated urethane polymer, plasticiser (e.g. diisodecyl phthalate), fillers (calcium carbonates), fumed silica, adhesion promoter, dehydrating agent, and catalyst (dibutyltin dilaurate). 

A model sealant is reported to exhibit high elongation and good tensile and tear strength. The sealant finds suitability as a low-to-medium-modulus construction joint sealant. 

Construction joint A joint at a predetermined location where two successive placements of concrete meet. 

EN 28339 1990 Building construction jointing products. Sealants determination of tensile property. 

ISO 6927 1981 Building construction jointing - producing sealants vocabulary. 

ISO 7389 1987 Building construction jointing product - determination of elastic recovery. 

ISO 7390 1987 Building construction jointing products - determination of resistance to flow. 

Where the space between such fixed points is 3 feet or less-for instance, two pump bases-and there is little likelihood of temperatures cycling over 20° to 30°F, it is possible to dispense with an expansion joint between them. However, if there is a steam jet that can play on the floor, or the possibility of the spillage of very hot, possibly boiling, liquids, then an expansion joint should be installed even in that small a space. The rule to follow is, install an expansion joint over (1) all points of movement expansion, control or construction joints or moving cracks in the substrate, (2) around or between all fixed points, including changes in direction or elevation of trenches except drains. 

Topping was applied over an expansion Joint, construction joint, or other point of movement in the substrate. (An expansion joint in the topping is required in sucli areas.)... 

Figure 16.3 is a vehicular tunnel in Baltimore. Water is shown entering in small amounts through a construction joint in the concrete. The volume of water was insignificant, but tiles could not be placed over the wet zone. Grouting with chemicals successfully stopped the seepage. 

When seepage occurs through widely spaced cracks or construction joints on a smooth surface, it is feasible to treat each crack or joint separately, often directly at its exposed location. Such was the case in the following job description which was done by grouting within a concrete dam, part of an electric generating facility in New Jersey. 

Leaks occurring at several points in the three access ways were a continual annoyance to maintenance and inspection personnel. They were found mainly along construction joints in the concrete structure and to a lesser extent in honeycombed areas in the concrete. Water at 35°F flowed from these points in well-defined streams, in some cases at 2 to 3 gpm. 

Sealing isolated cracks and construction joints is more generally done by pumping grout through packers placed in drilled holes. The following excerpt from the engineer s report describes typical field procedures ... 

Drilling Holes I Placement of Packers—One-inch holes were drilled in the vicinity of the leaks to the point of intersection of the construction joints, 8 to 10 inches from the surface. An electric handheld diamond coring drill was used. Next, packers were inserted in the holes and tightened to provide a pressure-tight seal. 

Waterstop Rx. [Am. Colloid] Water-prodSng for construction joints. 

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