Unconventional Construction Research Articles

Handheld Double Packer Equipment for Water Sampling and Hydraulic Measurements in Deep Boreholes

AbstractThe need 10 characterize deep and shallow bedrock hydrogeologic conditions in remote terrain encouraged the development of an inexpensive, last, and easily transporrable double packer sampler. The principal objective was to combine water sampling and hydraulic measurement with the same equipment. Unconventional construction that does not create any large hydraulic pressure differences in the equipment allows light and inexpensive standard materials and components to be used. The low cost, lightweight equipment can thus be operated by a single person.The equipment is based on the principle of using soft, hydraulically expandable packers that isolate the required section of the borehole. The inflation and deflation of the packers is controlled by a single tube, through which the water sample is also withdrawn. The uppermost part of the tube branches into two tubes; the pumping action is generated by cyclic pressure pulses applied to one of these tubes.The equipment has mainly been used in narrow 1,8‐inch (46 mm) diameter boreholes down to a depth of about 3280 feet (1000 m); versions capable of operating in larger boreholes and with higher pump capacity have also been constructed. At one sampling site, the chemical composition of water from an isolated fracture zone was compared with open hole water at the same depth. The water from the fracture had a different chemical composition compared with the mixed water sample from the open hole. To collect representative ground water samples, double packers and long pumping limes are required.The equipment characterizes both the hydraulically conductive bedrock structures and the chemical compositions of bedrock ground water. Through comparison to K‐values and chemical constituents in other portions of the borehole, the collected data can be used to estimate transport pathways, aquifer yield, travel times, and ground water evolution. The range of hydraulic conductivity measured with the equipment in association with this research was 10‐10 to 10‐7 m/s.

Ultimate capacity of blast loaded structures common to chemical plants

AbstractThere has been a great deal of investment in development of design criteria and design and construction of heavily reinforced, blast‐resistant control rooms. This remains the best option for protective construction against severe blast loading experienced close in to a vapor cloud or other explosion hazard. However, most structures encountered at chemical plants and contemplated for future construction are conventional steel frame, metal clad buildings. In this paper we look closely at the response of such buildings to explosion loads and their ability to undergo large deformations without structural failure. The types of structural elements evaluated include metal decking of various gauge and shape along with a variety of girt and purlin sections. Building frames or bents are also evaluated, although the date base for these is much more limited. The work is based on observations made during investigations of large explosion accidents along with analytical predictions and test measurements. To conclude, we offer specific design criteria and connection recommendations for enhancing the overall strength of a building through the use of conventional components in unconventional construction.

Circulating Water Tunnel Under Lake Ontario

This paper describes the engineering and construction features of the Circulating Water System (CWS) at the 643 MW Somerset Station located on the south shore of Lake Ontario, approximately 45.06 km (28 miles) northeast of Buffalo, New York. The paper discusses the aspects of the CWS that are unique to Somerset Station (including fish deterrent/fish return system, staged diffuser, intake velocity cap, etc.), and the provisions made in the design to satisfy the stringent licensing requirements of regulatory agencies having jurisdiction over the project such as the New York State Department of Environmental Conservation and the U.S. Army Corps of Engineers. Finally, the unconventional construction techniques which were used to enable the system to be built within the framework of a tight construction schedule and environmental constraints are discussed.

Torsion-bar spring and damping systems of tracked vehicles

The purpose of this paper is to present a descriptive outline of the features of torsion-bar spring and damping systems as they relate to suspension system performance for armoured and non-armoured military tracked vehicles. Special emphasis is given to less well known and unconventional constructions, which are often found in vehicles of historical interest, such as those employed between the First and Second World Wars.

Design of a Harpischord Soundboard and Bridge

A harpsichord built largely of fiberglass-reinforced polyester and epoxy has been designed with a soundboard and bridge of unconventional construction inspired by the classical flat-top guitar. The harpsichord strings terminate on the bridge instead of passing over it to a hitchpin rail on the frame. The “split-level” soundboard of glass-epoxy printed circuit board material is attached to the top of the bridge at the rear and to the bottom at the front. A prototype instrument was characterized by reasonably good tone quality but inadequate loudness. A series of simple experiments on samples of various soundboard materials interpreted with the aid of some bending-wave theory showed in what directions to change the soundboard and bridge parameters. The resulting instrument is considerably louder than the prototype and is judged to have better tone as well.

Using thyristors and diodes to improve commutation

Machines employing thyristor- and diode-assisted commutation (TAC and DAC) offer numerous advantages over conventional dc machines in applications where commutation is a problem. It is anticipated that the first practical developments will involve adaptations of present systems, followed at a later date by the introduction of more unconventional construction techniques.

Theoretical and Experimental Investigation of Indoor Flying Models

SummaryThe development of a special model aeroplane technique is reviewed which renders possible easy and illustrative experimenting In the Reynolds number regime from 1 to 5000. The models are built in extremely light-weight construction; with wing span from 0·1 to 1 metre and all-up weights from 0·01 to 2 grammes, flight velocities between 0·1 and 1 m/ sec are reached. The requirement of extremely low wing loading, together with the special air flow characteristics in this region, leads to rather unconventional construction principles with the materials balsa wood, nichrome wire and cellulose film. These principles are reviewed briefly. The problem of optimum propulsion for such model aeroplanes is treated analytically. Some results are given for flight performance optimisation. By combining theory and experiment there has been evolved, e.g. the Schwebeleistungs method (power required for horizontal flight) for optimising the duration of indoor model aeroplanes without exact knowledge of their aerodynamic characteristics. Flight characteristics with some elasticity of the structure present formidable problems and are reviewed in some examples. Finally, some problems of hangar meteorology are mentioned.