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Cement And Concrete | by Louis Carlton Sabin



That the use of cement has outstripped the literature on the subject is evidenced by the number and character of the inquiries addressed to technical journals concerning it. This volume is not designed to fill the proverbial "long felt want," for until within a few years the number of engineers using cement in large quantities was quite limited. These American pioneers in cement engineering, under one of whom the author received his first practical training in this line, needed no formal introduction to the use and properties of cement; their knowledge was born and nurtured through intimate association and careful observation.

TitleCement And Concrete
AuthorLouis Carlton Sabin
PublisherMcGraw Publishing Company
Year1907
Copyright1907, L. C. Sabin
AmazonCement and Concrete

By Louis Carlton Sabin, B. S., C. E., Assistant Engineer, Engineer Department, U. S. Army ; Member of the American Society of Civil Engineers.

-Preface
To-day the young engineer frequently finds a good working knowledge of cement one of the essentials of success, and the gaining of this knowledge by experience alone is likely to be too slow and expen...
-Part I. Cement. Classification And Manufacture. Chapter I. Definitions And Constituents. Art. 1. General Classification Of Hydraulic Products
1. The use of a cementitious substance for binding together fragments of stone is older than history, and it is known that the ancient Romans prepared a mortar which would set under water. So far as o...
-Art. 2. Lime. Common And Hydraulic
6. common lime is the product obtained by burning a pure, or nearly pure, carbonate of lime. On being treated with water it slakes rapidly, evolving much heat and increasing greatly in volume. It is n...
-Art. 3. Portland Cement
8. Definition Although questions may still arise as to whether a given product is entitled to the name Portland cement, yet ideas are now pretty well crystallized as to what shall be included under...
-Art. 3. Portland Cement. Continued
Expressing the above statement as a formula we shall have or, must not exceed one. The mean value of this ratio for twenty representative American brands is found to be .915. Values of .76 and ...
-Art. 4. Slag Cement
11. Slag cement is manufactured to a considerable extent in Europe and is beginning to assume some importance in the United States. It is a pozzolana cement in which the silica ingredient is supplied ...
-Art. 5. Natural Cement
13. Natural cement, as its name implies, is made from rock as it occurs in nature. Argillaceous limestones or argillo-magnesian limestones, having the proper proportion of clay, magnesia and lime, may...
-Chapter II. Manufacture. Art. 6. The Manufacture Of Portland Cement
15. Historical It is said that as early as 1810 a patent was obtained in England for the manufacture of an artificial product by calcining a mixture of carbonate of lime and clay. This, however, wa...
-Manufacture. Art. 6. The Manufacture Of Portland Cement. Part 2
Marl and clay.................. 14 Soft limestone and clay.............. 3 Hard limestone and clay.............. 28 18. General Description Of Processes The essentials of any method ...
-Manufacture. Art. 6. The Manufacture Of Portland Cement. Part 3
It may be remarked here that in the older form of the wet process, developed in England and formerly used here to some extent, the thin slurry was run into backs or shallow reservoirs to settle, the...
-22. Details Of The Manufacture. Preparation And Mixing Of The Raw Materials
The main points in the preparation of the raw material for burning are: First, the proper amount of each ingredient must enter the mixture; second, the materials must be reduced to an extremely fine s...
-Preparation And Mixing Of The Raw Materials. Part 2
23. Styles Of Kilns The various styles of kilns in use may be divided into four classes, namely: (1) common dome kilns, (2) Continuous kilns, (3) Chamber and ring kilns, and (4) Rotary kilns. The D...
-Preparation And Mixing Of The Raw Materials. Part 3
While until recently the ordinary length of a rotary kiln was 60 feet, it was realized that, especially for wet mixtures, a greater length was economical, and recently a much advertised plant has inst...
-Preparation And Mixing Of The Raw Materials. Part 4
28. Ball And Tube Mills The ball mill is perhaps in most common use for the first reduction. It consists of a short cylinder of large diameter partially filled with flint or steel balls. (See cut.)...
-Preparation And Mixing Of The Raw Materials. Part 5
30. Rolls Although rolls have not as yet been extensively employed for cement grinding, one mill has recently been equipped entirely with rolls for both coarse and fine grinding, and in other mills...
-Art. 7. Other Methods Of Manufacture, Of Portland Cement
34. Portland Cement From Blast Furnace Slag The preparation of a true Portland cement from blast furnace slag has been followed in Germany and elsewhere in Europe for several years, and recently ha...
-Art. 8. The Manufacture Of Slag Cement
36. Slag Cement Slag Cement is made by adding calcium hydrate to a granulated basic slag resulting from the manufacture of gray pig iron. The slag must be carefully selected as to its chemical comp...
-Art. 9. The Manufacture Of Natural Cement
38. History The American product called natural cement was first manufactured at Fayetteville, Onondaga County, N. Y., in 1818, and used in the construction of the Erie Canal. Other early dates of ...
-Art. 9. The Manufacture Of Natural Cement. Continued
There is little question that the cement rock used in most natural cement plants is capable of producing a much better and more uniform quality of product than is actually obtained. Many plants dep...
-Part II. The Properties Of Cement And Methods Of Testing. Chapter III. Introductory
43. In the tests of such structural materials as wood and steel it will not usually be difficult to determine the suitability of the material for the intended purpose, provided the test pieces truthfu...
-Chapter IV. Chemical Tests. Art. 10. Composition And Chemical Analysis
48. Value Of Chemical Tests The definite aid which chemical analysis may render in determining the quality of a cement is limited by the following considerations. It is not definitely known just wh...
-Chapter V. The Simpler Physical Tests. Art. 11. Microscopical Tests. Color
55. Microscopical examinations are of some interest and value to those who are thoroughly versed in the chemistry of the burning and hardening of cements, as an aid in determining the part played by e...
-Art. 12. Weight Per Cubic Foot Or Apparent Density
58. Significance Since a hard burned Portland cement will usually be heavier than a light burned one, a test of the weight per cubic foot was once thought to be of great value in judging of the deg...
-Art. 13. Specific Gravity Or True Density
62. The apparent density or weight per cubic foot is influenced to such an extent by the degree of fineness of the cement that this test has been almost superseded by the test for specific gravity. Al...
-Chapter VI. Sifting And Fine Grinding. Art. 14. Fineness
69. Importance Of Fineness The fineness of cement is always conceded to be one of its most important qualities, and the determination of fineness is omitted in none but the very crudest tests. Unfo...
-Sifting And Fine Grinding. Art. 14. Fineness. Continued
74. In Table 5 are given some of the results obtained by the writer which will serve to show what variations may exist in sieves which have been selected from a considerable number offered for use. ...
-Art. 15. Coarse Particles In Cement 80. The Effect Of Coarse Particles On The Weight Of Cement
To remove the coarse particles by sifting will reduce the specific gravity of a sample of Portland cement, as the un-ground particles are from the harder burned and denser portion of the clinker, and ...
-The Effect Of Coarse Particles On The Weight Of Cement. Part 2
It was found that in the case of Portland cement, neat, the highest result was obtained with the largest (40) per cent, of screenings, but with one and two parts sand, the strength steadily fell as la...
-The Effect Of Coarse Particles On The Weight Of Cement. Part 3
As to the sample composed of coarse particles reground, it must be considered that although this sample was passed through the No. 100 sieve, yet it was in reality much coarser than sample C, because ...
-Art. 16. Fine Grinding
89. Effect Of Fine Grinding On The Weight Of Cement Fine grinding will decrease the weight per cubic foot, the fine cement not packing as closely as the coarser product. In Cement for Users, by M...
-Art. 16. Fine Grinding. Continued
Reground samples of natural cement gain strength more rapidly than resifted samples, but eventually the strength attained is about the same. In Portland cements regrinding seems to be of greater value...
-Chapter VII. Time Of Setting And Soundness. Art. 17. Setting Of Cement
96. Process Of Setting When cement is gaged with sufficient water to bring it to a paste, and is then left undisturbed, it soon begins to lose its plasticity and finally reaches such a condition th...
-Time Of Setting And Soundness. Art. 17. Setting Of Cement. Part 2
103. An over-limed or highly limed cement is usually slower setting than an over-clayed one. Among natural cements, those of the aluminous variety are usually quick setting. Other things being equal, ...
-Time Of Setting And Soundness. Art. 17. Setting Of Cement. Part 3
108. The quantity of water used in gaging has a most important influence on the test for time of setting, an increased quantity of water retarding the setting. This may be seen from Table 20. Table...
-Time Of Setting And Soundness. Art. 17. Setting Of Cement. Part 4
116. Conclusions The purpose aimed at in the test for time of setting will, to a certain extent, regulate the method to be employed. The pressure of the finger nail will be sufficient to determine ...
-Art. 18. Constancy Of Volume
117. That a cement should not contain within itself elements which may lead to its destruction, is evidently a most important quality. It is probable that nearly all cements undergo a slight change in...
-123. The Warm Water Test
Mr. H. Faija was an early experimenter in accelerated tests for soundness, and about 1882 he began the use of a steamer, using a temperature of about 110 Fahr. After eleven years' use he still ...
-124. The Hot Water Test
The temperature to be userd in accelerated tests for soundness is a point which has received much attention and is still under discussion. In 1890 M. Deval described a series of experiments he had mad...
-126. Deval's Method
making tests of mortar briquets, which have been kept in hot water, seems, to be the most rational accelerated test for soundness. This method was used in Germany several years ago, when it was claime...
-130. M. H. Lechatelier's Method
The method recommended by M. H. LeChatelier for testing soundness requires the use of a cylindrical mold, about 1 1/4 inches in diameter and of about the same height, which is made of thin metal and s...
-130. M. H. Lechatelier's Method. Continued
Table 26. Cold And Hot Tests On Samples Of One Brand Of Portland Cement Cement. Parts. Sand Date Made. 1894. Age. Tensile Strength. ...
-137. Hot Tests For Natural Cements
All that has preceded concerning hot tests refers to their use for testing Portland cements. Very little is known concerning the value of hot tests for natural cements. There are comparatively few nat...
-Chapter VIII. Tests Of The Strength Of Cement In Compression, Adhesion, Etc
140. In testing the strength of cement the object is threefold : 1st, to obtain an idea of the strength that may be expected from the cement as used in the structure; 2d, to obtain a basis for compari...
-Art. 19. Tests In Compression And Shearing
141. Value Of Test In practically all forms of masonry construction, cement is called upon to resist compression. In consequence of this fact, the opinion is somewhat general that the greatest amou...
-Art. 20. Tests Of Transverse Strength
145. It is probable that the earliest rupture tests of cement were made by submitting rectangular prisms to a bending stress; but such tests have long held a place subordinate to trials of tensile str...
-Art. 21. Tests Of Adhesion And Abrasion
149. Adhesion The test for adhesion is also one of long standing, being used during that time when engineers were content with an approximate idea of what might be expected of an hydraulic product....
-Chapter IX. Tensile Tests Of Cohesion
158. The testing of cement by applying tensile stress to a previously prepared briquet, containing definite proportions of cement and water, or of cement, sand and water, is the strength test which is...
-Art. 22. Sand For Tests
159. Whether the tensile test should be applied to neat cement briquets or to those prepared from sand mortars has been a disputed point, but there are now but few authorities who recommend the use of...
-Art. 23. Making Briquets
163. Proportions The proportions of the ingredients should always be determined by weight rather than by measure. It will be found more convenient to use metric weights for the dry ingredients. The...
-Art. 23. Making Briquets. Continued
Table 29 shows similar results for mortars made with one, two and three parts sand. With one part sand the wet mortar made from Gn, 21 R, which gave but 22 pounds per square inch at seven days, gave 4...
-169. Temperature Of The Ingredients And Of The Air Where The Briquets Are Made
The temperature of the mortar and of the air in which the briquets are prepared is a matter of some moment. In 1877, Mr. Maclay 1 reported a series of experiments on Portland cements from which conclu...
-172. Gaging By Hand
The objects to be attained in gaging are to thoroughly incorporate the cement and sand, to evenly distribute the water throughout the mass, and, if possible, to give the mortar a certain tenacity rese...
-173. Hoe And Box Method
Mr. Alfred Noble used for many years a form of gaging apparatus, consisting of a box with sloping bottom, in which the mortar is worked by means of a hoe. The author has used an iron box made on this ...
-174. Machine For Mortar Mixing
As the mixing by hand is a rather slow and tedious method, and the hoe and box method are not very generally known, several machines have been devised to do the work. None of them, however, has given ...
-175. Steinbruch's Mortar Mixer
Steinbruch's Mortar Mixer is a German machine operating on a different principle. It consists of a circular shell having on its upper side and near its outer edge a circular groove, or trough, to rece...
-175. Steinbruch's Mortar Mixer. Continued
179. Form Of Briquet Suggested As a result of experiments which will be described under the head of Clips,1 (Art. 25) the following conclusions were drawn as to the desirable features for a briqu...
-187. Method Recommended
In making briquets by hand, the mortar may well be packed into the molds by the fingers, which should be protected by rubber tips. When the mold is filled and slightly heaped, the trowel should be pla...
-Art. 24. Storing Briquets
190. The Time In Air Before Immersion As soon as the briquets are molded they should be covered with a damp cloth until they are ready to be removed from the molds, when they should be transferred ...
-192. Water Of Immersion
When the briquets are ready to be immersed, i.e., usually, twenty-four hours after made, they are placed in a tank, containing water that is kept fresh by frequent renewals. The water in the tank shou...
-194. Stale Water
Some experiments made to compare the strength of briquets which were alike in all other respects, but were immersed in different tanks in which the water had not been frequently renewed, showed very c...
-197. Other Methods Of Storing Briquets
It has been thought that briquets, made to test cement that is to be used in air, should be hardened in the same medium in order that the tests should more nearly approach the conditions of use. Sever...
-Art. 25. Breaking The Briquets
198. The Testing Machine The function of the testing machine is simply to furnish a means of applying the tensile stress, and of measuring the amount of force required to break the briquet. Aside ...
-208. Strength Of Briquets That Develop Clip-Breaks
It was also found in breaking 277 briquets with two styles of clips without cushions that 129 of them that gave clip-breaks averaged 611 pounds per square inch, while 148 which did not develop clip-br...
-213. Effect Of Improper Adjustment
The effect of not properly adjusting the briquets in the clip was also investigated. In some cases the briquets were placed in the proper position as nearly as possible. In the other cases they were i...
-214. Conclusions Derived From Tests Of Several Styles Of Clips
From the tests described above,1 the following conclusions may be drawn: 1st When using the ordinary form of clips with metal gripping points, the briquets which break at the places of contact...
-220. Treatment Of The Results
The number of briquets which are made to test the strength of a given sample of cement will depend on the accuracy which it is desired to attain. If but two briquets are made, neither of the results m...
-Art. 26. The Interpretation Of Tensile Tests Of Cohesion
225. One of the problems presented in the inspection of cement is to foretell the ultimate relative strengths of two samples from the results of short time tests. Formulas have been presented ...
-226. Comparative Tests Of Portland Cements
In Table 40 are given the results of tests on four brands of Portland cement at seven days, twenty-eight days and two years. From the tests at two years it appears that T and U are the best cements, V...
-227. Comparative Tests Of Natural Cements
From the nature of natural cements a much greater variation in strength among different brands, and even among different samples of the same brand, is to be expected. With Portland cements made in acc...
-228. Several Samples Of One Brand
To show that short time tests do not always indicate the relative values of several samples of cement, even when all of the samples are of the same brand, Tables 42 and 43 are given. All of the result...
-Chapter X. The Reception Of Cement And Records Of Tests. Art. 27. Storing And Sampling
231. Storage The storage houses provided for the cement should be such as will effectually preserve it from dampness, the floor being dry and strongly built. A circulation of air under the floor ...
-Art. 28. Records Of Tests
235. Value Of Records In conducting work in which the use of cement enters as a prominent factor, it is not only necessary to know that the cement used is of a good quality, but also to be able to ...
-Art. 28. Records Of Tests. Continued
244. Acceptance Or Rejection If all of the tests on a given sample are satisfactory, the date of acceptance is placed in the proper column of the barrel book. It only remains then to mark the ...
-Part III. Preparation And Properties Of Mortar And Concrete. Chapter XI. Sand For Mortar
246. Mortar When cement is mixed with sand and water, the resulting paste is called mortar. The term neat cement mortar is sometimes used to designate a cement paste without sand, but when the ...
-Art. 29. Character Of The Sand
247. Various kinds of rock are capable of producing sand of good quality. The natural sands are usually siliceous in character, but calcareous sands are also met with and may give excellent results ...
-Art. 29. Character Of The Sand. Continued
252. Sand For Use In Sea Water It has been said that granitic sands when used in sea water do not give good results on account of the felspar of the granite being attacked by the cement when the ...
-Art. 30. Fineness Of Sand
253. The size and shape of the grains are important elements in the quality of sand. Considering grains of the same shape but differing in size, the larger grain will have a smaller surface area in ...
-Art. 31. Voids In Sand
256. Conditions Affecting Voids The voids present in a given mass of sand will depend upon the shape of the grains, the degree of uniformity in size of grains, the amount of moisture present, and ...
-Art. 31. Voids In Sand. Continued
Table 56. Varying The Granulometric Composition Of River Sand. Effect On Value Of, For Use In Cement Mortar Composition of Sand as to Fineness. Tensile Strength, Pounds per S...
-Art. 32. Impurities In Sand
264. The usual specification for sand is that it shall be clean, sharp and siliceous. We have shown that it need not be siliceous, and we have also noted that one authority considers that it need ...
-Art. 33. Conclusions. Weight. Cost
267. Requirements For Good Sand In conclusion, then, we may say that good sand may consist of grains of almost any moderately hard rock that is not liable to future alteration in the work. The ...
-Chapter XII. Mortar. Making And Cost. Art. 34. Proportions Of The Ingredients
270. Capacity Of Cement Barrels Since there is no standard size for cement barrels, the capacities vary considerably, Portland cement barrels ranging from 3.1 to 3.6 cu. ft., while natural cement ...
-272. Quantity Of Sand
The amount of sand to be used in mortar will depend entirely on the character of the work and the quality of the cement and sand. If it is merely a matter of strength to be developed, no special care ...
-274. Equivalent Proportions By Weight And Volume
As cement is now so frequently sold in sacks of one-fourth barrel each, in which the cement is not so compact as in a barrel, we have assumed the contents of a barrel to be 3.45 cu. ft. for Portland, ...
-276. Richness Of Mortar
Mortars containing small amounts of sand are often stronger than neat cement mortars. Especially is this true of most natural cements. Some of these will give as high strengths when mixed with two par...
-277. Effect Of Pebbles
If the sand contains pebbles, the proportions should be considered in a little different way. Suppose we make a one-to-three mortar with sand that contains ten per cent, of pebbles. We have in reality...
-278. Amount Of Water For Mortar
The amount of water required for mortar will vary with the proportion of sand to cement, the character and condition of the ingredients, the weather, and the purpose which the mortar is to serve. If t...
-Art. 35. Mixing The Mortar
281. Having decided upon the proportions of cement, sand and water, it remains to incorporate these into a plastic, homogeneous mass. The size of the batch should be so adjusted, if possible, that a ...
-282. Hand Mixing
For hand mixing, a water tight platform or shallow box should be used, of such a size that the given batch will not cover the bottom more than four inches deep. If the sand is measured, a bottomles...
-283. Machine Mixing
Where large quantities of mortar are required, machine mixers are sometimes used. A very complete plant for mortar-making was used in building the Titicus Dam.1 In this case machinery was used in meas...
-Art. 36. Cost Of Mortar
285. Ingredients Required For One Cubic Yard Of Mortar The character of the ingredients used in making cement mortar varies so much that it is difficult to accurately determine the quantities of ...
-287. Explanation Of Tables
The first section of Table 60 gives the amount of materials required for Portland cement mortar when the proportions are stated by weight; the second and third sections refer to proportions by volume ...
-288. Estimating Cost Of Mortar
With the data given in Tables 60 and 61 and a knowledge of unit prices of the materials used in the mortar, one may estimate the Cost of the materials in a given quantity of mortar. The cost of the mi...
-Chapter XIII. Concrete. Aggregate
291. Cement concrete is composed of a mixture of cement mortar and fragments of stone, brick or other moderately hard substances to which the mortar may adhere. Put in place while plastic, it soon ...
-Art. 37. Character Of Aggregate
292. Material For Aggregate Many of the points mentioned concerning the selection of a good sand are also applicable to broken stone. The latter may be produced from almost any moderately hard ...
-Art. 38. Size And Shape Of The Fragments And The Volume Of Voids
297. As in the case of sand, the shape of the fragments and the degree of uniformity in size have an important effect on the proportion of voids in the mass, and all of these elements affect the ...
-Art. 38. Size And Shape Of The Fragments And The Volume Of Voids. Continued
302. In determining the value of a certain material for aggregate, at least six characteristics are to be considered, the strength and durability of the stone, the size and shape of the fragments, ...
-Art. 39. Stone Crushing And Cost Of Aggregate
304. Breaking Stone By Hand When but a small quantity of concrete is to be made, and broken stone cannot be purchased in the vicinity, the stone for concrete may be broken by hand. This is an ...
-Chapter XIV. Concrete Making. Methods And Cost. Art. 40. Proportions Of The Ingredients
311. Concrete is simply a class of masonry in which the stones are small and of irregular shape. The strength of the concrete largely depends upon the strength of the mortar; in fact, this dependence ...
-Art. 41. Mixing Concrete By Hand
317. Necessity Of Thorough Mixing Too much stress can hardly be laid upon the necessity of thoroughly mixing the concrete if the best results are to be attained. It has already been shown that ...
-Art. 42. Concrete Mixing Machines
324. General Classification Concrete mixing machines may be divided into two general classes, batch mixers and continuous mixers. In the former, sufficient materials are proportioned to make a ...
-Art. 42. Concrete Mixing Machines. Continued
330. The Mckelvey Mixers2 The Mckelvey Mixers2 are made in two styles, continuous and batch. Both styles are cylinders revolving on friction rollers, and having, on the interior, deflecting blades ...
-Art. 43. Concrete Mixing Plants And Cost Of Machine Mixing
337. Coosa River Improvement The concrete plant used at Lock No. 31, Coosa River Improvement,2 was erected in a three-story shed. The top story served as a cement storage room and two hoppers were ...
-Art. 43. Concrete Mixing Plants And Cost Of Machine Mixing. Continued
341. Quebec Bridge The plant used in the construction of the Quebec Cantilever Bridge2 consists of a No. 5 rotary stone crusher, with a maximum capacity of thirty cubic yards per hour, discharging ...
-Art. 44. Cost Of Concrete
345. Quantities Of Ingredients In A Cubic Yard As has already been indicated, the rational method of proportioning concrete is to use just sufficient mortar to fill the voids in the stone, or ...
-Art. 44. Cost Of Concrete. Part 2
.9 bbl. cement at $2.46 (including $0.59 per bbl. storage)................. $2.214 .28 cu. yd. shell, at $0.45 per cu. yd.......128 .47 sand, at 0.12 ......056 .80 stone, at 2.95 ...
-Art. 44. Cost Of Concrete. Part 3
Items. Cost per Cu. Yd. of Concrete, Cents. Quarrying (exclusive of 8.3 cents for explosives) 8.2 19.2 Crushi...
-Chapter XV. The Tensile And Adhesive Strength Of Cement Mortars And The Effect Of Variations In Treatment. Art. 45. The Tensile Strength Of Mortars Of Various Compositions And Ages
354. The Proportion Of Sand The rate of change in the strength of mortars as the proportion of sand is increased varies greatly for different cements. The fineness and chemical composition of the ...
-Art. 46. Consistency Of Mortar And Aeration Of Cement
360. Effect Of Consistency Of Mortar On Tensile Strength The results in Table 73 are from briquets of Portland cement with two parts Standard crushed quartz. The consistency of the mortars ...
-Art. 47. Regaging Cement Mortar
364. The Effect Of Thorough Gaging The value of thorough gaging is a point frequently overlooked in the preparation of mortars and concretes. Table 78 gives a few of the results obtained in ...
-Art. 47. Regaging Cement Mortar. Continued
Table 82. Regaging Natural Cement Mortar Ref. Cement. Sand. Tensile Strength, Pounds per Square Inch, for Mortars Receiving Different Treatment. ...
-Art. 48. Mixture Of Cement With Lime, Etc
369. Mixture Of Portland And Natural Cements For certain uses mortar is sometimes made from a mixture of Portland and natural cement, with the idea of retaining some of the properties of the ...
-Art. 48. Mixture Of Cement With Lime, Etc. Part 2
Table 87. Slaked Lime In Portland Cement Mortars Ref. Lime in form of Proportions. Tensile Strength, Pounds per Square Inch., Sample Stored in ...
-Art. 48. Mixture Of Cement With Lime, Etc. Part 3
Table 92. Plaster Of Paris In Cement Mortars, Hardening In Dry Air. Effect On Different Samples, Portland And Natural Ref. Cement. Age Briquets. Tensile...
-Art. 49. Mixtures Of Clay And Other Materials With Cement
380. Effect Of Clay On Cement Mortar And Concrete Clay may occur in cement mortar or concrete due to the use of sand or aggregate that is not clean. As the plasticity of cement mortar is increased ...
-Art. 49. Mixtures Of Clay And Other Materials With Cement. Continued
Table 98. Effect Of Clay On The Tensile Strength Of One-To-Three Mortars Cement. Parts Sand to One Cement. Age of Briquets When Broken. Tensile St...
-Art. 50. The Use Of Cement Mortars In Freezing Weather
389. It is frequently desirable to use cement in freezing weather, but to ensure good work under these circumstances it is necessary to take certain precautions. If mortar is frozen immediately after ...
-Art. 50. The Use Of Cement Mortars In Freezing Weather. Part 2
a, briquets stored in water in laboratory, b to f, inclusive, briquets stored in open air after twenty-four hours in air of laboratory. a and 6, fresh water used for gaging mortar. c, d, e and f...
-Art. 50. The Use Of Cement Mortars In Freezing Weather. Part 3
e to h, stored in open air, January, Northern Michigan. water used: a and e, 10.4 per cent, fresh water. b and f, 11.9 per cent, fresh water. c and g, 13.3 per cent, fresh water. d and h, 11.9 pe...
-Art. 51. The Adhesion Of Cements
398. The Adhesion Between Portland And Natural Cements The question sometimes arises as to whether Portland cement will adhere to natural .cement already set, and whether fresh natural and ...
-Art. 51. The Adhesion Of Cements. Part 2
Materials a Hammered bar iron. b Potsdam sandstone, cleavage surface. c Drummond Id. limestone, cleavage surface. d Ground plate glass. e Kelleys Id. limestone, sawn surface. ...
-Art. 51. The Adhesion Of Cements. Part 3
409. Tensile tests were made of briquets from mortars similar to those used in the adhesive tests and stored in damp sand, and the results are used for comparison with the adhesive tests. The ...
-Art. 51. The Adhesion Of Cements. Part 4
Table 122. Adhesion Of Cement Mortar To Brick. Effect Of Lime Paste In Portland Cement Mortar Hardened in Cohesion or Adhesion. Tensile Strength, Pounds per ...
-Art. 51. The Adhesion Of Cements. Part 5
1 In computing adhesion, or shear, or pounds pull per square inch of area in contact, perimeter considered circumference of a circle of diameter equal to the distance between opposite edges of rod aft...
-Chapter XVI. The Compressive Strength And Modulus Of Elasticity Of Mortar And Concrete. Art. 52. Compressive Strength Of Mortar
418. The compressive strength of cement mortar is from five to ten times the tensile strength. As the result obtained in tests of either compression or tension depends upon the shape and size of the ...
-Art. 53. Compressive Strength Of Concrete With Various Proportions Of Ingredients
421. With the increasing use of concrete in arch bridges, in foundation piers and in columns of buildings, and especially in connection with steel in beams, etc., the compressive strength of the ...
-Concrete With Various Proportions Of Ingredients. Continued
426. Turning to the question of the amount of mortar, it is plainly shown that the concrete containing forty per cent, is but little better than that containing thirty-three per cent. This is in line ...
-Art. 54. Concretes With Various Kinds And Sizes Of Aggregates
429. It has already been stated that the character of the aggregates is second only to the quality of the mortar in its effect on the strength of concrete. The materials available for aggregate in ...
-Art. 55. Cinder Concrete, Etc
433. For such purposes as floors for buildings, cinders are used in concrete to a considerable extent on account of their light weight. Cinder concrete weighs only from two-thirds to three-fourths as ...
-Art. 56. The Modulus Of Elasticity Of Cement Mortar And Concrete
437. With the increasing use of concrete and steel in combination, the modulus of elasticity of cement mortar and concrete assumes a new importance, since the ratio of the stresses in the two ...
-Art. 56. The Modulus Of Elasticity Of Cement Mortar And Concrete. Continued
The modulus of elasticity of twelve-inch mortar cubes, one volume cement to one volume sand, was, for loads between five hundred and one thousand pounds per square inch, 3,461,000 at seven days and 5,...
-Chapter XVII. The Transverse Strength And Other Properties Of Mortar And Concrete. Art. 57. Transverse Strength
443. Tensile, Transverse And Compressive Strengths Of Mortar Compared The tests given in Tables 146 and 147 were designed to compare the strengths of cement mortars in tension, bending and ...
-Transverse Strength. Part 2
447. Variations In Richness Of Mortar In Table 148 several concretes made with mortars having different proportions of sand are compared, and the results of briquet tests on similar mortars are ...
-Transverse Strength. Part 3
452. Variations In Size Of Stone And Volume Of Voids The bars given in Table 153 were all made with mortar composed of three parts sand to one of Portland cement by weight. The stone for these ...
-Transverse Strength. Part 4
456. Deposition In Running Water A few tests were made to show the effect of depositing concrete in rapidly running water. The molds were placed in the stream and weighted down in twelve inches of ...
-Art. 58. Resistance To Shear And Abrasion
458. Shearing Strength The shearing strength of mortars and concretes is of importance not only because of its intimate relation to the compressive strength, but because of the shearing stresses ...
-Art. 59. The Expansion And Contraction Of Cement Mortar, And The Resistance Of Concrete To Fire
462. Change In Volume During Setting Cement mixtures shrink somewhat when hardened in air, while specimens stored in water expand a trifle during hardening. Although several experiments have been ...
-The Resistance Of Concrete To Fire. Continued
467. Behavior In Conflagrations As to the behavior of concrete-steel arches in an actual fire, a board of experts was appointed by the insurance companies to investigate the causes and extent of ...
-Art. 60. The Preservation Of Iron And Steel By Mortar And Concrete
471. The rusting of steel members in modern buildings and other engineering structures is one of the most serious menaces to their permanence. The introduction of concrete-steel construction has ...
-Art. 61. Porosity And Permeability. Efflorescence. Pointing. Use In Sea Water
478. The porosity and permeability of mortars have been thoroughly investigated by M. Paul Alexandre, who has published his results in Recherches Experimentales Sur Les Mortiers Hydrauliques.1 The ...
-Efflorescence. Pointing. Use In Sea Water. Part 2
All of the above conclusions indicate that a mortar may be quite porous, and yet so long as the voids are very minute, the percolation of water through it will be slow. This is especially shown by the...
-Efflorescence. Pointing. Use In Sea Water. Part 3
Mr. W. C. Hawley 3 employed a stock solution of two pounds caustic potash, five pounds powdered alum, and ten quarts water, and used in the finishing coat three quarts of this solution in each batch o...
-Efflorescence. Pointing. Use In Sea Water. Part 4
495. Cements In Sea Water The theory of the action of sea water upon cements is not fully understood. It is known that some cement structures exposed to the worst conditions have given most ...
-Part IV. Use Of Mortar And Concrete. Chapter XVIII. Concrete. Deposition
501. Concrete may be molded into blocks which are allowed to set and then are transported to the structure and laid as blocks of stone. This is the block system of construction. The adaptability of ...
-Art. 62. Timber Forms Or Molds
503. The construction, placing and removal of forms frequently represent a considerable percentage, from five to thirty per cent., of the total Cost of the concrete, and it is therefore evident that ...
-Art. 62. Timber Forms Or Molds. Continued
508. Joints And Corners If desired, triangular strips may be nailed to the inside of the forms in such a way as to block off the face to represent stone masonry, and in this way the marks of ...
-Art. 63. Deposition Of Concrete In Air
515. Transporting To Place Of Deposition In depositing the concrete in place,.care must be taken not to undo the work of mixing. If the concrete is allowed to fall freely a distance of several ...
-Art. 63. Deposition Of Concrete In Air. Part 2
521. Another class of rubble concrete differing from the above more in degree than in kind, is formed by placing large stones in the work, and filling the joints between them with a rather wet ...
-Art. 63. Deposition Of Concrete In Air. Part 3
527. A good finish may be obtained when the molds are smooth if the workmen will force the blade of a spade or shovel between the fresh concrete and the mold, and pull the handle away from the mold. ...
-Art. 63. Deposition Of Concrete In Air. Part 4
A somewhat similar method is employed in giving to concrete the appearance of cut stone. The materials used in the surfacing mortar are Portland cement and crushed rock, the character of the rock depe...
-Art. 64. Placing Concrete Under Water
537. In building a concrete structure under water where the site cannot be coffered, it must be expected that the expense of the work will be increased, and the quality of concrete poorer. The ...
-Art. 64. Placing Concrete Under Water. Part 2
1 Third Annual Report, Boston Transit Commission. 541. This principle was employed by Mr. Daniel W. Mead in placing concrete in a small shaft in ninety feet of water.1 An eight inch, wrought iron p...
-Art. 64. Placing Concrete Under Water. Part 3
547. Depositing Concrete In Bags The second method of depositing concrete under water, namely, by placing the freshly mixed concrete in coarse sacks and immediately lowering them to place, is very ...
-Art. 64. Placing Concrete Under Water. Part 4
1 From London Engineering, quoted in Engineering News, Vol. xxvii, p. 551. It is evident that this method of depositing concrete in large sacks is peculiarly suited to forming a foundation on a sof...
-Chapter XIX. Concrete, Steel
558. The ratio between the compressive and tensile strengths of steel is nearly unity. The same thing is approximately true of wood and some other materials of construction. In cement and concrete, ...
-Art. 65. Monier System
560. A much more picturesque beginning of the concrete-steel industry is furnished in the story, quite true, that about 1876, a French gardener, Jean Monier, used a wire netting as the nucleus about ...
-Art. 66. Wunsch, Melan, And Thacher Systems
564. Wunsch System This system, which was invented in 1884 by Robert Wunsch of Hungary, consists of two iron members of angle irons and plates imbedded in concrete, the lower member being arched ...
-Art. 67. Other Systems Of Concrete-Steel
571. The Hennebique System The rods are here arranged in pairs, one above the other, in a vertical plane. In girders, the bar in the tension side is straight, while the other one of the pair is ...
-Art. 68. The Strength Of Combinations Of Concrete And Steel
579. While we have in this country been somewhat slow in acknowledging the worth of concrete-steel construction, there is now a strong interest displayed in the subject; many experiments are being ...
-Art. 69. Concrete-Steel Beams With Single Reinforcement
584. Definitions In this discussion the word strain has its technical meaning, the relative change in length of a piece under stress. It is usually expressed as the ratio of the elongation (or ...
-Art. 69. Concrete-Steel Beams With Single Reinforcement. Part 2
Then if A B in Fig. 13 now represents fc and M S = fs, we have as before: The total stress on the concrete above the neutral axis is now represented by the area within the parabola, or (2/3)f...
-Art. 69. Concrete-Steel Beams With Single Reinforcement. Part 3
Solving, we have yl = 6 inches nearly, and y2 = 10 6 = 4 inches. From (4): Substituting values of yl, y2, fc, Ec and Es, we have fs = 6,667 lbs. per sq. in. From (5): And az ...
-Art. 69. Concrete-Steel Beams With Single Reinforcement. Part 4
Mod.Elas. Concrete 1,000,000. 2,000,000. 3,000,000. 4,000,000. Working Stress of Concrete in Compression. Moment E...
-Art. 70. Concrete-Steel Beams With Double Reinforcement
598. We have seen that when the depth of a beam is limited by structural considerations we may increase the normal load by excessive reinforcement, but that this method results in low stresses in the ...
-Art. 71. Shear In Concrete-Steel Beams
600. There are several methods of failure of concrete-steel beams other than those considered above, direct tension in the steel or direct compression in the concrete due to the bending moment. These ...
-604. Illustration
Let us consider a concrete-steel beam twelve inches wide, twelve inches deep and of ten foot span, supported at the ends; reinforcement, one square inch of metal properly distributed in a plane two in...
-605. Value Of Shear
The same total stress of 3,600 lbs. must be transferred through the concrete immediately above the bar. If the reinforcement is so distributed that the entire width of the beam has practically the sam...
-607. Resistance To Shear
When provision against shear is made by using small steel rods placed either vertical or inclined downward toward the center of the beam, as mentioned above, these rods may well be made in the form of...
-Chapter XX. Special Uses Of Concrete. Buildings, Walks, Floors And Pavements. Art. 72. Buildings
609. While the use of concrete and steel for the walls and floors of buildings is about fifty years old, yet it is only in comparatively recent years that its value has become generally known. It is ...
-619. Strength Of Columns
When a column reinforced with longitudinal bars is subjected to pressure, the concrete and steel must shorten together. The relative stresses in the two materials will then be proportional to their mo...
-621. Hooped Concrete
In extended experiments on what he has called hooped concrete, M. Considere 2 has shown that reinforcement is much more important and beneficial in a transverse or circumferential direction than if...
-624. Forms For Buildings
One of the most serious problems in the construction of concrete-steel buildings is the designing of the forms. They must be as light as is consistent with strength to facilitate handling. They should...
-628. New York Building Regulations
While city building regulations are not always criteria of good practice, yet the Regulations of the Bureau of Buildings of the Borough of Manhattan concerning the use of concrete-steel construction a...
-Art. 73. Concrete Walks
630. One of the most important uses of concrete is in the construction of street and. park walks. It has not only driven stone nagging almost out of use, but it is being employed to a large extent in ...
-633. Wearing Surface
The preparation and application of the wearing surface require much care if satisfactory results are to be obtained. The most evident service of this layer is to withstand wear, and it should therefor...
-634. The Construction Of The Walk
If the walk has not a considerable longitudinal slope, it should be given a transverse slope of about a quarter inch to the foot to provide for draining the surface. Stakes for grade and line havin...
-640. Cost Of Concrete Walk
The cost of concrete walks varies from ten cents to twenty-five cents per square foot. A fair price for a walk of average quality where there are no special difficulties is twelve to eighteen cents pe...
-Art. 74. Floors Of Basements, Stables And Factories
643. The principles governing the laying of walks apply also in a general way to the construction of floors that rest directly on the ground. For residences, basement floors may be laid with three ...
-Art. 75. Concrete In Pavements And Driveways
648. Pavement Foundations The principal use of concrete in connection with city pavements has been as a foundation, the wearing surface being of some other material, as brick, asphalt, cedar ...
-Art. 76. Curbs And Gutters
654. The use of concrete for curbs and gutters is rapidly increasing. Curbing is sometimes molded and afterward put in place like stone curbing, but the greatest advantages in the use of concrete for ...
-Art. 77. Street Railway Foundations
659. The heavy motor cars used on city and urban electric railways subject the track to very severe service. As the head of the rail must be practically flush with-the pavement on city streets, cross-...
-Chapter XXI. Special Uses Of Concrete (Continued). Sewers, Subways, And Reservoirs. Art. 78. Sewers
664. There seems to be no very good reason why concrete is not more generally employed in the construction of all large sewers. With sizes less than two or two and one-half feet in diameter the ...
-Special Uses Of Concrete (Continued). Sewers, Subways, And Reservoirs. Art. 78. Sewers. Continued
1 E. J. McCaustland, Trans. Assoc. C. E., Cornell University, 1902. 669. The bottom of the trench being cut to form, the concrete for the invert was laid directly on the sub-grade, tamped in layers...
-Art. 79. Concrete Subways And Tunnel Lining
677. The advantages of concrete in subway construction and in tunnel lining are now well established. In subways built in open cut, the side walls and invert are of concrete built in place, while the ...
-Art. 79. Concrete Subways And Tunnel Lining. Part 2
683. Tunnel Lining In Soft Ground For tunnels in soft ground requiring the use of a shield, some difficulties in using a concrete lining are apparent. The principal one of these lies in the fact ...
-Art. 79. Concrete Subways And Tunnel Lining. Part 3
689. Cascade Tunnel In the construction of the Cascade Tunnel of the Great Northern Railway a somewhat different arrangement was used.1 The working platform in the tunnel was erected five hundred ...
-Art. 80. Reservoirs. Linings And Roofs
697. Although the choice of the material with which to construct a reservoir may in some cases be varied by local conditions, it is found that under ordinary circumstances concrete offers the ...
-Art. 80. Reservoirs. Linings And Roofs. Part 2
The determination of the stresses in a groined arch roof is complicated not only by the peculiar form of the arch itself, but by the fact that the spandrels of the arches are filled with concrete over...
-Art. 80. Reservoirs. Linings And Roofs. Part 3
The floor consisted of six inches of concrete, 3/8 inch cement mortar, one coat liquid asphalt and one coat harder asphalt. The slope lining was of six inches concrete, one coat asphalt, one layer of ...
-Chapter XXII. Special Uses Of Concrete (Continued) Bridges, Dams, Locks, And Breakwaters. Art. 81. Bridge Piers And Abutments And Retaining Walls
718. The use of concrete in large bridge piers was at first confined to the hearting or backing of stone masonry shells. It was soon found, however, that in many cases the concrete was able to ...
-Special Uses Of Concrete (Continued) Bridges, Dams, Locks, And Breakwaters. Art. 81. Bridge Piers And Abutments And Retaining Walls. Continued
1 Trans. A. S. C. E., December, 1893. 725. Retaining Walls And Abutments Concrete is used very largely for constructing retaining walls and bridge abutments. The foundations of a retaining wall ...
-Art. 82. Concrete Piles
732. Piles may be made of concrete either with or without steel reinforcement. In the former case they are built in place, but where steel is used the piles are usually driven after they have been ...
-Art. 83. Arches
737. The use of concrete in the construction of arch bridges is becoming so extended and diversified that it would require a volume by itself to adequately cover the subject, and such a treatment of ...
-Art. 83. Arches. Part 2
1 Engineering News, Sept. 21, 1899. The beauty of a concrete arch may easily be marred by faulty design, and some very ugly, as well as some very beautiful, arches have been erected. 742. Stone ...
-Art. 83. Arches. Part 3
The division between adjacent voussoirs should be clearly marked on the face, and additional joints may be indicated if desired, by lines in a plane approximately perpendicular to the line of pressure...
-Art. 83. Arches. Part 4
752. Expansion joints were provided in the spandrel arches at the ends, two at each pier and one at each abutment, to allow some movement due to changes in temperature. The expansion joints were made ...
-Art. 84. Dams
758. Concrete Vs. Rubble Concrete has been employed to some extent in most of the important masonry dams of recent construction, and has formed the main portion of some of the largest dams yet ...
-Art. 85. Locks
767. The use of concrete in the construction of canal locks is comparatively recent, but it has met with much favor, and its use is extending. The requirements for a lock wall are that it shall be ...
-Art. 86. Breakwaters
776. The use of concrete in the construction of breakwaters in the United States was suggested as early as 1845. In recent years it has been employed quite extensively, especially for harbor ...
-Chapter XXIII. Concrete Building Blocks, Their Manufacture And Use
782. History Concrete building blocks are formed by molding plastic mortar or concrete into shapes resembling blocks of stone used in building construction. The blocks are usually hollow, but ...
-Art. 87. General Methods Of Manufacture
783. The apparatus used in making concrete blocks is called a machine, although in its essentials it is merely a mold, and becomes a machine only because of the appliances provided to facilitate the ...
-Art. 87. General Methods Of Manufacture. Continued
The block is now carried, either by hand or cart, to the curing shed, where it is laid on scantlings to admit the air on all sides equally. In case any accident happens to a block in course of manufac...
-Art. 88. Materials And Finish
790. Character Of Materials For Mortar And Concrete It is unnecessary to repeat here the requisites for proper materials for mortar and concrete. The cement required for concrete blocks is first-...
-Art. 89. Cost And Laying
795. Cost Of Blocks Concrete blocks are usually made to lay courses eight inches or nine inches high, and are for 8-inch, 10-inch, and 12-inch walls. The blocks themselves may be of any length, ...
-Art. 89. Cost And Laying. Part 2
The Cost of mixing concrete in large quantities is seldom less than 30 cents per cubic yard if allowance is made for plant. This is for mixing alone, not including placing. The Cost for hand mixing is...
-Art. 89. Cost And Laying. Part 3
1,400 brick at $9.00 per thousand.......... $12.60 Mortar to lay................... 3.10 Labor to lay 1,400 brick............... 7.00 Cost of 100 sq. ft. 8-inch brick wall.........$22.70 T...
-Art. 90. Strength Of Concrete Blocks, And Building Regulations
801 Strength The materials and proportions used in the manufacture of concrete blocks vary so widely that it is difficult to give any general statements concerning their strength. With a knowledge ...
-Art. 90. Strength Of Concrete Blocks, And Building Regulations. Part 2
9. Provided that no hollow concrete building blocks shall be used in the construction of any building in the city of Philadelphia, unless the maker of said blocks has submitted his product to the full...
-Art. 90. Strength Of Concrete Blocks, And Building Regulations. Part 3
No allowance should be made in figuring the modulus of rupture for the hollow spaces. 10. The compression test shall be made as follows: Samples must be cut from blocks so as to contain a full web ...
-Appendix I. Progress Report Of Committee On Uniform Tests Of Cement, American Society Of CIVIL Engineers
Presented at the Annual Meeting, January 21, 1903, and Amended at the Annual Meeting, January 20, 1904. Your Committee on Uniform Tests of Cement has devoted much time, and given very careful consi...
-Report Of Committee On Uniform Tests Of Cement. Part 2
14. (2) The whole quantity of the powder is introduced, and the level of the liquid rises to some division of the graduated neck. This reading plus 20 cu. cm. is the volume displaced by 64 gr. of the ...
-Report Of Committee On Uniform Tests Of Cement. Part 3
Time Of Setting 37. Significance The object of this test is to determine the time which elapsed from the moment water is added until the paste ceases to be fluid and plastic (called the initial...
-Report Of Committee On Uniform Tests Of Cement. Part 4
58. Method The material is weighed and placed on the mixing table, and a crater formed in the center, into which the proper percentage of clean water is poured; the material on the outer edge is tu...
-Appendix II. Report Of Committee On Standard Specifications For Cement, American Society For Testing Materials
Adopted by the Society, November 14th, 1904. General Observations 1. These remarks have been prepared with a view of pointing out the pertinent features of the various requirements and the preca...
-Appendix III. New York Section, Society For Chemical Industry
method Suggested for the Analysis of Limestones, Raw Mixtures, and Portland Cements by the Committee on Uniformity in Technical Analysis with the Advice of W. F. Hillebrand. Solution One-half gr...







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