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Drilled pile foundations in porous, pinnacled carbonate rock
Published in Barry F. Beck, Felicity M. Pearson, Karst Geohazards, 2018
At this project, Project #2, it was found in many drilled holes that small voids were present within a rock mass that otherwise was suitable for supporting the piles. The contractor attempted to grout several sockets with small voids 0.1 to 0.15 m (4 to 6 inches) wide. Because the grout was fluid, it tended to flow into the voids instead of filling the socket. To overcome these difficulties, the contractor used geotextile tubes or “socks” to bridge the voids (Figure 4). Specially fabricated tubes, available from several geotextile manufacturers, having a diameter equal or slightly larger than the rock socket diameter, were attached to the reinforcing steel bars. For each pile where a “sock” was used, a small amount of grout was placed at the bottom of the hole. The “sock” was clamped to the bottom of the reinforcing bar with a hose clamp. A grout tube was inserted into the top of the “sock” and the top also was clamped. After this assembly was inserted into the hole, with the bottom embedded in the grout at the bottom of the hole, grout was pumped into the “sock,” which contained the grout and prevented it from flowing into the void. After the “sock” was grouted, the space above the “sock” also was grouted.
Facility Grounding
Published in Jerry C. Whitaker, Electronic Systems Maintenance Handbook, 2017
All coax and waveguide lines must include grounding kits for bonding the transmission line at the antenna [9]. On conductive structures, this can be accomplished by bonding the tail of the grounding kit to the structure itself. Remove all nonconductive paint and corrosion before attachment. Do not drill holes, and do not loosen any existing tower member bolts. Antenna clamping hardware can be used, or an all-stainless-steel hose clamp of the appropriate size can be substituted. The location of the tower-top ground is not as critical as the bottom grounding kit.
Determination of Fluoride Content of the Atmosphere and Plant Tissues (Manual Methods)
Published in James P. Lodge, Methods of Air Sampling and Analysis, 2017
Dimensions of the column are not critical and many types, available from suppliers’ stocks, are usable. A column made of borosilicate glass tubing 10-mm ID and 16 cm long, having a fritted glass disc fused into the constricted base, and a reservoir of about 100 mL capacity at the top, is satisfactory. A short piece of polyvinyl chloride tubing attached to the bottom and closable with a screw hose clamp permits adjustment of flow rates and prevents complete drainage of liquid from the column.
Frost susceptibility of sub-base gravel used in Pearl-Chain Bridges: an experimental investigation
Published in International Journal of Pavement Engineering, 2018
M. S. M. Lund, K. K. Hansen, I. B. Andersen
The upper part of the specimen was removed so that its top surface aligned with the top of the mould, and the acrylic mould and spacer disc were removed from the steel mould. To copy the most vulnerable field conditions, the specimen was saturated with water prior to the freeze–thaw test. The approach used to saturate the specimen deviated from the approach described in the ASTM D5918-13 standard (ASTM Standard D5918-13 2013), since it was performed by water absorption where the bottom of the specimen was placed in water reaching 50 mm up the sides of the specimen. The spacer disc was removed, and then a fine mesh of 73 m and a coarser mesh of 10 mm were placed below the specimen. The coarse mesh was fastened to the sides of the specimen using a hose clamp. The fine mesh prevented any material from being washed out. The specimen was allowed to absorb water for three days, since preliminary tests had shown that the mass of the specimens with all types of gravel remained constant after three days.
Experimental characterization of the undrained instability and steady state of silty sand soils under monotonic loading conditions
Published in International Journal of Geotechnical Engineering, 2018
Abdellah Cherif Taiba, Youcef Mahmoudi, Mostefa Belkhatir, Abdelkader Kadri, Tom Schanz
Numerous studies have reported that behaviour of sand can be greatly influenced by samples reconstitution. Dry funnel deposition used in this study is one of the most important methods to evaluate the liquefaction resistance. All the samples have been reconstituted with the diameter of 100 mm and the height of 200 mm (H/D = 2). The height to diameter ratio of 2 was selected in order to minimise the effects due to end platens of the apparatus and to reduce the likelihood of buckling during testing Bayat and Bayat (2013). The samples were prepared with the help of a mould comprising of two semi-cylindrical shells. The two shells can easily be joined or embossed one with the other with the help of a hose clamp. In order to maintain the cuff made of latex along the partitions of the mould, four aspiration ducts are pierced in the conducted shells. These ducts communicate with the inside of the mould by rows of small holes. They were joined to flexible hoses that were assembled in a single tube. This last one can be connected to a vacuum pump. The mass of sand–silt mixture to be put inside the mould with a help of funnel was calculated referring to the initial relative density expressed by the following equation:
An investigation into wayside hot-box detector efficacy and optimization
Published in International Journal of Rail Transportation, 2020
Constantine Tarawneh, James Aranda, Veronica Hernandez, Stephen Crown, Joseph Montalvo
The bearing surface temperatures along the inboard and outboard raceways were measured using four K-type spring-loaded bayonet style thermocouples. To accommodate the bayonet thermocouple holders, each bearing adapter was drilled and tapped. The bearing surface temperature was also measured using seven standard K-type thermocouples equally spaced around the circumference of the bearing at the spacer ring location (see Figure 4). These thermocouples were held tightly in place using a hose clamp.