B I B L I O G R A P H Y OF FOREIGN P U B L I C A T I O N S

Measurement of Longitudinal Deformations.* The continually increasing degree of uti l ization of the strength properties of the materials in the construction of members and structures, a reduction in the safety factor, and the el imination of l imitations on cross-sectional dimensions on the basis of construction considerations have led to the need for a rel iable and careful static analysis of the projected structures. The purpose of such an analysis is the exact determination of the stress state of the structure under the loads which may act during its operation. The methods of analysis based on the laws of the theory of elast ici ty or the theory of plast ici ty permit determining the stresses in a theoret ical way; however, pract ical analyses are frequently accompanied by mathemat ical difficulties.

In such cases, the results of stress or strain measurements constitute highly valuable auxiliary data as a means for reducing, simplifying, and facil i tat ing the analyt ical work. However, for an exper imental determination of the static behavior of members or structures, conforming to the required rel iabil i ty, it is necessary to have accurate measuring instruments and trained personnel. For a clear formulation of the measurement problem, the investigator should picture the distribution of forces in the structure being studied, and for an exact interpretation of the results of the measurements, he should be able to apply the principles of the theory of statics of structures.

The value of instrumental measurements in engineering practice is substantially enhanced when these results are carefully processed, especial ly if i t is possible to compare the measurement data with the results of approximate analyses made using simplified assumptions. Such processing and comparison of the measurement data el iminates superfluous investigations: an excessively large mass of experimental data causes the investigator to lose control so that their processing becomes extremely difficult; under unfavorable circumstances the convenience of carrying out the investigations may be questioned.

The book here reviewed answers the problem of securing improved results from the investigations in the above- mentioned formulation of their basic purpose- to obtain sufficiently re l iable measurement data for use in the solu- tion of pract ical engineering problems.

The content of the book is divided into the following 11 chapters.

1. Principles of the Theory of Strength (pages 1-57, 37 figures, 8 references). The authors discuss here the basic concepts relating to the stress state: plane stress, stresses and their components, principal stresses and their directions and graphical representation; general stress state. Strains and strain s t a t e - plane, general, principal strains, graphical representation of the strain field. Geometrical and physical equations - Hooke's law for plane and general stress state; basic stress equations and their solution, plates. The equation for the plane stress state and its analysis in polar coordinates.

2. Deformation Measurements (pages 58-75, 14 figures, 1 table, 6 references). Basic concepts, devices for measuring and calibrating deformations, conducting measurements, and processing their results. Sources of errors in deformation and measurements.

3. Nonelectric Devices for Measuring Deformations(pages 76-91, 21 figures, 6 references). Mechanical de- vices for direct measurement of deformations, lever-actuated devices, devices with meters, dynamic devices and their installation. Optical and pneumatic devices.

4. Stress Investigations by Lacquer Coatings (pages 92-106, 13 figures, 11 references). Quali tat ive evalua- tion of cracks in coatings, materials for lacquer coatings, types of coatings and methods of applying them, and quantitative evaluation of crack field.

5. Strain Gages (pages 107-201, 50 figures, 13 tables, 33 references). Since at the present t ime the measure- ment of deformations by means of strain gages had undergone great changes, special attention is devoted to it in the

* F. Thamm, Gy. Ludwig, I. Aus~az, and I. Santo, Dehnungsmessverfahren, 328 pages, figures, references, Akad4- miai Kiado (Academy of Sciences of the Hungarian People's Republic), Budapest (1971).

Translated from Gidrotekhnicheskoe Stroitel 'stvo, No. 4, 59-60, Apr i l 1973.

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BIBLIOGRAPHY OF FOREIGN PUBLICATIONS 403

book: the authors describe the basic types of strain gages; the factors which lower the accuracy of the measurements and the measures for counteracting their effects (hysteresis, creep, temperature sensitivity, resistance to insulation, heating of gages); preparations for the measurements (selection of measurement sites and types of gages, methods of fastening them, installation of conductors, protection against external action); measurement techniques (measure- ment of resistances, balanced and unbalanced bridges, potentiometers, control of measurements); and special meas- urements (measurement of large deformations, determination of internal stresses).

6. Inductive Ga~es (pages 202-212, 9 figures, 12 references). Measurement principles, connection schemes. and techniques for carrying out measurements by using inductive gages.

7. Electrical Meters and Recording Devices (pages 213-244, 12 figures, 9 tables, 41 references). Meters for static and dynamic measurements, cathode-ray and loop oscillographs, recording and magnetic devices, and statisti- cal processing of test results.

8. Wire-StrainGages (pages 245-255, 14 figures, 3 references). Measurement principles, construction forms of wires, distribution of measurement spots in the structures, and processing of test results.

9. Measurement of Deformations by the Grid Method (pages 256-270, 12 figures, 10 references). Determina- tion of plane stress state by means of grids installed on the surface of the investigated structure; determination of total principal stresses from variat ion of thickness in interference charts; and investigation of plates.

10. Measurement of Elongations by Using X Rays (pages 271-296, 17 figures, 16 references). Measurement principles and techniques for measuring deformations by means of x rays; measurement of linear displacements; de- termination of the stress state on the basis of classical principles, difficulties associated with them, and ways of overcoming these difficulties; and preparation of surfaces of structures for investigations.

11. Processing and Uti l izat ionof Measurement Results,Modeling Laws (pages 297-323, 13 figures, 2 tables, 4 references). Direct measurements on investigated structure; util ization of results of measurements carried out on models; enumeration of results of measurements at other load levels; and modeling laws (exact laws for measure- ment of elongations, approximate laws, and modeling laws for special types of loads). The book ends with a subject index.

I t might be well to point out the concise and laconic style of the subject matter, which is at the present-day level of knowledge in the field of deformation measurement, as well as the use of foreign experience and literature in the preparation of the book. The theoretical analyses included in the basic sections, in which the authors justify the basic measurement principles, discuss the possible errors and their causes, and examine ways of e l iminat ing them, make this an especial ly interesting book. Because of this conciseness, the book can be regarded as a manual. The technical l i terature on the theory and practice of engineering measurements does not abound in books so care- fully prepared and so profound in their content, yet of l imited size, as this one. For this reason, this Hungarian book will occupy a deserving place in the present-day scient i f ic- technical l i terature devoted to the investigation of struc- tures and construction elements.

Hydraulic Engineering (Budapest).* The issue No. 4, 1971 of these Proceedings includes the following articles of interest for the readers of our Journal (the articles have detailed summaries in Russian, English, French, and German):

K. Shtel'tser, "Determination of the characteristics of the motion of bed loads by applicat ion of the theory of probability" (pages 335-360, 9 figures, 6 tables. 10 references). The author presents a method of analysis of the function of distribution of the "virtual veloci ty" v b of bed loads, which is a function of the distribution of the lengths of the paths traversed by the sediment particles during the t ime T. It is shown that the complex relation involving the flow, the channel, and the bed load is uniquely expressed by the quantity v b. The distribution function of v b is determined in the following manner: a) the probable distributions of the lengths of the path traversed by the par- ticles in one jump are determined; b) the same distributions are determined for the part icle traveling during t ime T in n jumps; c) after knowing a) and b), taking into account al l the possible jumps made during t ime T, the distribu- tion function 0n is determined and, by dividing the obtained variable probabili ty by T, the required distribution function is obtained, which is the final result for v b. Laboratory and ful l -scale tests carried out by using radioactive tracing substances gave results which confirmed the data obtained by applying the relation derived by the author.

* Uiziigyi K0zlemdnyek, Proceedings of the Scientific-Research Institute for Water Management of Hungary [in Hungarian].

404 BIBLIOGRAPHY OF FOREIGN PUBLICATIONS

T. Gal and Sh. Kovach. "Intersection of old river channel during the construction of a levee" (pages 397-403, 10 figures). To remove thin layers of noncompacted silts lying along a levee, a narrow temporary dike was con- structed with a high specific pressure on the foundation; under the action of the loads, the silt was compressed on both sides of the dike. To accelerate the process, charges were detonated in holes along the foundations under the slopes of the dike; 9.4 hours after the blasts, the settlement of the dike was 1-1.2 m. Further sett lement of the dike was negligible. The levee withstood successfully the loads caused bythe high flood of 1970.

L. Mesarosh, "Measurement of density and water content of soil in the body of a dike by meam of radioactive isotopes" (pages 404-410, 5 figures, 7 references). The seepage regimen in a dam during the passage of a flood wave was studied by use of a series of observation welB, using radioactive indicators for measuring the density and water content of the soils in the body of the structure.

Hydraulic Engineering (Budapest), No. 1, 1972.

D. Bognar, "Hydraulic engineering and its construction industry" (pages 3-13). The author discusses the hy- draulic structures which are characteristic for water management development in Hungary: the work carried out in connection with the construction of these structures and the characteristic features of this work (levees and dams, erosion-control structures and elements, construction of unlined canals, linings for regulation structures, carrying out of hydraulic engineering work by the hydromechanization method, etc.); relation between hydraulic structures and the environment; and relation between construction work and local and c l imat ic conditions. These characteristics of hydraulic construction should be taken into account in the design and construction of the structures.

L. Nemeti, "Probabilistic methods of analysis of hydrologic phenomena" (pages 14-27, 3 figures 1 table, 5 references). The author describes a probabilistic method of carrying out hydrologic analyses and presents a detailed numerical example which can be used by specialists who have not had experience with such analyses, for determin- ing the basic hydrologic data required for water management planning.

I. Marko, "Design of heads of chutes" (pages 28-37, 9 figures, 5 references). In this article, the basic types of heads of chutes are considered (with frontal and lateral spillways; different shapes of the transition zone between the spillway and the chute) and the hydraulic conditions of operation of each type of head are discussed.

I. Chuka, "Use of network graphs in hydraulic construction" (pages 38-49, 5 figures, 9 tables). The author sets forth the basic concepts involved in the preparation of network graphs, as applied to the planning of hydraulic construction, and presents a simplified analysis of the corresponding algorithm.

I. Bogardi, "Protection capaci ty of flood-control dikes on rivers with wide flood plains" (pages 50-56, 4 figures, 7 references). The protection capacity is determined from an analysis of the possibility of the dike being destroyed, which is calculated on the basis of the probability of occurrence of the factors which are the most fre- quent causes of the destruction of dikes - high floods accompanied by wave action. The wave action depends upon the width of the flood plain, whose vegetation lessens the waves (for the case of forest belts, a relation is given which permits determining the reduction of the wave height). The method is applicable to analysis of structures and reservoir banks experiencing the action of waves under variable water levels, which are stat is t ical ly studied.

D. Shebeshten, F. Shtvertetski, A. Sabom, and A. Verda, "Investigation of cavitat ion in pumps by an indirect method" (pages 57-74, 15 figures). The authors describe a method for the quantitative evaluation of the develop- ment of cavitation in pumps in terms of the noise attending this phenomenon; they present a curve for the relation between the cavitation coefficient (in a new form proposed by the authors) and the measured noise. The end of the article is published in the issue No. 9., 1979., pages 19.4-144 of the Proceedings.

D. Illesh, "Data on water supply in the German Federal Republic" (pages 75-76, 2 figures, 2 tables). The author points out the substantial increase in the specific consumption of water (from 86 l i ters /day per capita in 1965 to 123 l i ters /day per capi ta in 1970). Among the sources of water supply, ground water predominates (53%), The water supply systems are developing in the direction of the construction of large purification plants serving extensive areas.

I. Marko, "Impervious membrane linings for reservoirs in earth" (pages 77-81, 4 figures, 1 reference). The author discusses the techniques for placing linings and describes the constructional characteristics of a membrane lining for the crest of a dike. An example of a reservoir with a membrane lining in Hungary is described.

BIBLIOGRAPHY OF FOREIGN PUBLICATIONS 405

L. Palosh, "Flow measurement by inductive methods" (pages 05-09, 3 figures. 1 table. 9 references). The author sets forth briefly the principles of the electromagnetic method of measuring flows, and mentions the fields in which it can be advantageously applied, depending upon the cost of the measurements (the characteristics of possible alternatives are presented in a table).

Proceedings of the Scientific-Research Institute for Reclamation (Bucharest), XXIV, 1072. The series on hy- draulic research contains five articles by A. Spfitaru, which cover different aspects of wave hydraulics: "Investiga- tious in the field of applicat ion of theoretical solutions of the wave-motion equations" (pages 5-20, 9 figures, 3 tables, 16 references); "Semiempir ical solution of wave equations for finite water depths" (pages 31-48, 8 figures, 1 reference); "Determination of the wave height in the diffraction zone" (pages 57-67, 6 figures, 5 references); "Method of determining the profile of an earth slope subjected to wave action" (pages 77-88, 8 figures, 1 reference); "Transformation of waves during their collision with structures" (pages 09-112, 10 figures, 3 tables, 4 references). The section devoted to lake science includes an article by R. Negru: "Unleveling of a lake under wind action" (pages 128-142, 6 figures, 5 references). The section devoted to the study of river mouths includes an art icle by A. Spfitaru: "The mouth of the Sulina Branch on the Black Sea" (pages 151-185, 29 figures, 2 tables, 10 references). Al l articles have detai led summaries in French, English, and Russian.