Evaluation of Gap-Graded Asphalt Concrete Mixtures Part II: Statistical Design and Analysis, HR-157, 1973

This report presents the results of a comparative laboratory study between well- and gap-graded aggregates used in asphalt concrete paving mixtures. A total of 424 batches of asphalt concrete mixtures and 3, 960 Marshall and Hveem specimens were examined. The main thrust of the statistical analysis conducted in this experiment was in the calibration study and in Part I of the experiment. In the former study, the compaction procedure between the Iowa State University Lab and the Iowa Highway Commission Lab was calibrated. By an analysis of the errors associated with the measurements we were able to separate the "preparation" and "determination" errors for both laboratories as well as develop the calibration curve which describes the relationship between the compaction procedures at the two labs. In Part I, the use of a fractional factorial design in a split plot experiment in measuring the effect of several factors on asphalt concrete strength and weight was exhibited. Also, the use of half normal plotting techniques for indicating significant factors and interactions and for estimating errors in experiments with only a limited number of observations was outlined,

Evaluation of Gap-Graded Asphalt Concrete Mixtures Vol. 3. Appendix, HR-157, Volume 3 (Part 3), 1972 (1973)

This report presents the results of a comparative laboratory study between well- and gap-graded aggregates used in asphalt concrete paving mixtures. A total of 424 batches of asphalt concrete mixtures and 3,960 Marshall and Hveem specimens were examined. There is strong evidence from this investigation that, with proper combinations of aggregates and asphalts, both continuous- and gap-graded aggregates can produce mixtures of high density and of qualities meeting current design criteria. There is also reason to believe that the unqualified acceptance of some supposedly desirable, constant, mathematical relationship between adjacent particle sizes of the form such as Fuller's curve p = 100 (d/D)n is not justified. It is recommended that. the aggregate grading limits be relaxed or eliminated and that the acceptance or rejection of an aggregate for use in asphalt pavement be based on individual mixture evaluation. Furthermore, because of the potential attractiveness of gap-graded asphalt concrete in cost, quality, and skid and wear resistance, selected gap-graded mixtures are recommended for further tests both in the laboratory and in the field, especially in regard to ease of compaction and skid and wear resistance.

Missouri riverfront parkway & scenic highway design study, 1973.

This report concerns a proposed Parkway and Scenic Highway along both sides of the Missouri River in Harrison, Pottawattamie and Mills County in Iowa and Washington, Douglas and Sarpy Counties in Nebraska. This Parkway will make the Missouri River valley accessible to the public, link existing and planned attractions and facilitate planned development while at the same time preserving for posterity the best of the natural attributes of the area.

Summary of Legislation: Iowa General Assembly, 1973

This summary of legislation enacted by the General Assembly has been prepared for the use of legislators and other interested parties. The summary of each legislative enactment has been assigned to a major subject category. This compilation provides interested persons with quick reference to legislation enacted in specific areas and generally informs persons of the contents and effective date of the legislation. NOTE: This is a large file and may take a few minutes to load.

Methods to Increase Durability of Reactive ("D" Cracking) Coarse Aggregate in Portland Cement Concrete, MLR-73-01, 1973

The coarse aggregates used for Portland Cement concrete in southwest Iowa have exhibited a poor serviceability. This early failure is attributed to a characteristic commonly referred as "D" cracking. "D" line cracking is a discolored area of concrete caused by many fine, parallel hairline cracks. "D" line cracking is primarily caused by the movement of water in and through coarse aggregate with a unique pore structure. The presence of the water in the aggregates at the time of freezing causes the "D" cracking to occur and early failure. By making the pore structure less permeable to moisture, it is thought the durability factor of the concrete should increase. By drying the aggregate before mixing and then mixing with the cement, the particles of cement should enter the outer pore structure, and upon hydration make the pore structure less permeable to moisture.

Iowa public library information, 1973.

This is the first in an annual series of in-depth surveys of the public library scene in Iowa. The report includes two main sections: an enlarged directory consisting of five separate smaller directories and an expanded library statistical survey.

[6 lettres autographes signées de Jules Barbier à Henri Heugel, 1897]

23 janvier 1897. Au sujet de ses droits d'auteurs. - 26 mars 1897. Demande une avance. - 1er avril 1897. A bien reçu son avance pour le mois de mai et redemande encore de l'argent à son éditeur. - 24 mai 1897. Demande à nouveau de l'argent. - 31 juillet 1897. Conteste une dette de 1700 francs qu'il aurait contractée avec Heugel. Lui demande de vérifier dans ses livres de caisse. - 29 octobre 1897. Papier bordé de noir. L'informe qu'il prononcera quelques mots à l'occasion de l'inauguration du monument d'Antonin Mercié

Puolueen vai herätysliikkeiden kirkkopolitiikkaa? : Keskustapuolueen kirkkopolitiikan kehitys vuosina 1973 ja 1974

Zusammenfassung: Kirchenpolitik einer Partei oder von Erweckungsbewegungen? : die Entwicklung der Kirchenpolitik der finnischen Zentrumspartei 1973 und 1974

[Album de 32 phot. de la ligne de chemin de fer de Voiron à Saint-Béron par Saint-Laurent-du-Pont, offert par le conseil d'administration du chemin de fer Voiron-Saint-Béron en 1897]

Donateur : Chemin de fer Voiron-Saint-Béron

El Centre d'Estudis Històrics de Llagostera (1966-1973)

Aquest treball pretén, en primer lloc, analitzar la història del Centre d’Estudis de Llagostera. Durant les dècades dels quaranta, cinquanta i seixanta a les comarques gironines es creen un seguit de centres d’estudis amb la missió de fer recerca del passat a través de l’arqueologia. En segon lloc, pretén saber quina consideració tenia l’arqueologia després dels primers anys del règim franquista. En tercer lloc, es pretén estudiar com va renéixer l’arqueologia al municipi de la mà d’uns pocs membres cultes de la societat civil, la qual cosa ens permet esbossar com neixen les inquietuds pel descobriment dels orígens de la vila. En quart lloc, es pretén, recuperar la memòria oral mitjançant entrevistes a aquells membres cultes van que encara viuen al poble. El contacte amb aquestes persones que van estar immerses en el desenvolupament del Centre d’Estudis ha permès compilar alguns documents gràfics que posseïen alguns d’ells a les seves biblioteques particulars