Abstract: An essentially non-dissipative, strap-free, continuously adjustable power unit inherently impervious to shorts and open circuits for powering repeaters in a T1 or similar telephone span line is disclosed. The unit uses a pulse-width modulated inverter in the converter input circuit to produce a variable-voltage D.C. output to the span line. The pulse width or duty cycle of the inverter is controlled by a control logic which senses the span line current and maintains it at a selectable predetermined level without any apreciable power dissipation.

Abstract: In a measuring device for integral values formed over a time span which is constantly up-dated, the system being one in which pulses represent a fixed quantity of the value being measured, the pulses are stored in a random access memory of a microcomputer with the central processing unit of the microcomputer sequentially addressing individual memory cells, in a repetitive manner after each sweep of the time span.

Abstract: This paper presents a comprehensive review on a case-study basis of concrete cable-stay bridges either completed, under construction or in design, with the intent of encouraging designers to consider the feasibility of this type of structure. Evolution of concrete cable-stay bridges is traced from Torroja's Tempul Aqueduct in Spain, completed in 1925, to present day design concepts. Particular attention is given to structure concept, geometric configuration, design considerations, structural details, and method of construction. As late as 1970, the practical span limit of steel cable-stay bridges was considered to be 300 m (1,000 ft). Recently, concrete cable-stayed bridges are considered technically feasible with spans approaching 500 m (1,600 ft). It has been projected that with an aerodynamically shaped composite concrete and steel deck a span of 700 m (2,300 ft) can be achieved. With today's technology of prefabrication, prestressing, and segmental cantilever construction, it is obvious that cable-stay bridges are extending the competitive span range of concrete construction to dimensions that had previously been considered impossible. The technological means exist, they only require implementation. /Author/

Abstract: A Growing-Reforming Procedure has been proposed in the previous paper. First, in this paper, some applications of the Growing-Reforming Procedure to beam structures are shown. The shapes with uniform strength are obtained by this procedure. Some applications are shown for (1) a cantilever beam loaded uniformly along the span, (2) a fixed-end beam loaded at the center, (3) a fixed-end beam loaded uniformly, (4) a spatially restricted beam with the same conditions as (3), (5) a fixed-end beam with an extended evaluation of shearing stress. Next, a modified method of forming arch structures is presented. This modified method is applied to some typical problems. Comaprison of beam structures with arch structures is made. The features of the obtained shapes are discussed.

Abstract: Systems construction techniques have recently been used in the widening and replacement of numerous substandard or deteriorated short-span bridges in Virginia. The techniques involve the mass production of precast concrete components to one or more standard dimensions. Standard designs have been used for precast slab superstructures in the 3.1-9.1 m (10-30 ft.) span range, and for precast, prestressed single T-beams in the 9.1-20.1 m (30-66 ft.) span range. A modular precast parapet has been developed to accommodate all span lengths. Other modular concrete components that have been used include the channel beam, box beam, I-beam, and permanent bridge deck form. Evaluations have shown that the use of these mass produced components can minimize bridge costs; the same forms can be used many times and costly on-site forming and form removal are eliminated. Also investigations have shown that the use of precast components enables a reduction in on-site construction time that provides motor vehicle fuel savings for construction personnel and the traveling public. The experience in Virginia suggests that systems construction is an economical and operationally efficient method for widening or replacing short-span bridges. /Author/

Abstract: PURPOSE:To provide an overhead traveling crane device advantageous for structural design and antivibration by shortening the span and reducing the weight of the crane.

Abstract: Analysis of the dynamic action of a moving bending moment on a single-span beam-type system showed that, with v=(0.2–0.8v10, taking account of the inertial forces of the load does not enter into the margin of strength of the construction, and these forces must be taken into consideration in dynamic calculations. The greatest deflections of the beam, when the mass of the load M=0.5ml, exceed the static deformations, taking account of the inertial forces of the load, by 2.5 times. The value of the velocity here is v=0.6v10.

Abstract: One of the few exact non-linear solutions applying to adhesive debonding is for the deformations in a pressurized thin plate strip of infinite length subjected over its span to externally applied pressure and temperature. For example, if the ends of the span are clamped (bonded) to a substratum leaving an unbonded span to be loaded by pressure or temperature, critical values of these latter quantities, at which debonding may occur, can be calculated using an energy balance criterion. To date, only the limiting cases of the general thin plate solution have been used to deduce these critical pressure or temperature loadings: (1) the plate thickness to span ratio is sufficiently large that nearly all the strain energy is in bending, i.e., the “thick plate” case, and (2) the opposite case wherein the ratio is sufficiently small that mainly stretching energy is involved, i.e., the “membrane”. This last case, for example, has applications to the adhesion of paints and coatings. The purpose of this pape...

Abstract: Forced vibration analysis of two dimensional bridge deck structures involves complex mathematical procedures and therefore analysis is often based on beam idealization of equivalent plates. This simplification yields close agreement only for long span bridges where plate action is relatively insignificant. However, such a concept of beam idealization cannot be successfully utilized in the case of short span bridges where plate action is predominant and where the determination of the distribution of dynamic deflections and amplification factors at critical sections of such plates is of prime concern. The principal objective of the present investigation is the forced vibration analysis of longitudinally stiffened, simply supported orthotropic bridge decks utilizing a new concept of interconnected beam idealization. The theoretical analysis deals with determination of amplification factors and dynamic deflections along critical sections of the plate treated as a series of interconnected beams. The aspect rat...

Abstract: This paper presents the seismic analysis of a typical aircraft hangar structure being constructed at Bombay for Indian Airlines Corporation. The main supporting structure has a very heavy mass at the roof level and a few large size columns of height to depth ratio ranging between 2.5 to 4.0. The main objective of this investigation is to study the effect, on the magnitude of seismic forces, of (i) large variation in masses at various floor levels and (ii) inclusion of shear deformation in columns and large moment of inertia of beams in the column region. The results obtained by modal analysis on the basis of recommendations of IS; 1893-1975, are compared for the two cases (a) considering the above referred two effects and (b) neglecting the two effects.