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The fire resistance of precast prestressed concrete floor systems is heavily influenced by the end connections and the stiffness of the surrounding structure, both of which must be considered in any analysis. Analysing floor slabs with beam or shell elements whose end nodes share the nodes of supporting beams leads to a major problem for precast prestressed flooring systems where the steel tendons terminate at the end of the flooring units, because the approach of sharing nodes of the supporting beam and floor assumes that these tendons are anchored into the supporting beams. In order to solve this problem, a "multi-spring" connection element has been developed. Experimental data available from previous research work has been used to validate the finite element model. It is concluded that the inclusion of the multi-spring connection results in more accurate predictions of prestressed hollowcore slab behaviour in fire conditions.

This paper reviews the research carried on effects of fire on the mechanical and thermal properties on concrete. Fire in the structure causes higher temperature at the concrete surface, which causes a reduction in compressive strength, modulus of elasticity of concrete. Though concrete is a poorer conductor than steel, sustained high temperature at the surface leads to progressive heating of the inner layers of concrete. This leads to exposing reinforcing bars to higher temperature; which causes a reduction in the yield stress, ductility and tensile strength of steel. This paper also focuses on the concrete cover, the reinforcement bars in a concrete structure are protected against fire only by the concrete cover layer thus higher is the cover more is the resistance and vice a versa. Effects of temperature on the thermal conductivity of concrete is also discussed in detail.

This research investigated the fire performance and failure behaviour of timber-concrete composite floor systems currently under development in New Zealand, resulting in a design method for evaluating the fire resistance of these floors with different types of connections. Furnace tests were performed on two full-size floor specimens at the Building Research Association of New Zealand (BRANZ). Both floor specimens were 4 m long and 3 m wide, consisting of 65 mm concrete topping on plywood formwork, connected to double LVL (laminated veneer lumber) floor joists. They were tested over a 4 m span, subjected to a nominal design live load of 2.5 kPa. Both floors were subjected to the ISO 834 test fire for over 60 minutes. Two separate connection types were tested; concrete notches cut into the timber beams with an incorporated shear key, and metal toothed plates pressed between the double beams.

It was found that the reduction in section of the timber beams due to the fire governed the failure mode of the floors. The test data and visual observations aided in the development of an analytical model for evaluating the fire resistance of timber-concrete composite floors. This was implemented into a spreadsheet that is able to predict the expected fire resistance of these floors, taking into account some major time dependent variable properties that can have an effect on the overall performance. Load-span tables have been produced to give the estimated fire resistance of floors with differing dimensions, span lengths and applied loads.

This paper describes numerical modelling to predict the fire resistance of engineered timber-concrete composite floor systems. The paper describes 3D numerical modelling of the floor systems using finite element software, carried out as a sequential thermo-mechanical analysis. Experimental testing of these floor assemblies has also been undertaken to validate the models, with multiple full scale tests conducted to determine the failure mechanisms and assess fire damage to the system components. The final outcome of this research is the development of simplified design methods for calculating the fire resistance of a wide range of engineered timber floor systems, as part of a larger research project on multi-storey timber buildings.

The fire resistance evaluation of a timber member is an important and complex problem of structural design. In order to solve this problem, it is crucial to have reliable information on the temperature distribution within a timber cross-section exposed to fire, and to develop a numerical model for the prediction of such a quantity. The paper reports the experimental-numerical comparisons in terms of temperature distribution within a timber member made from radiata pine LVL (laminated veneer lumber) exposed to fire. The experimental tests were performed at the University of Canterbury and BRANZ (New Zealand) on 146×60, 300×105 and 360×133 mm LVL members. The temperature distribution was monitored using several thermocouples. The numerical results were obtained using the Abaqus FE code with different conductive models. The Eurocode 5 and Frangi's proposals led to similar results characterized by acceptable approximation close to the surface. Since the accuracy reduced for deeper fibres, a new proposal based on a different variation of the conductivity with the temperature was made. The proposal led to acceptable approximation throughout the tested cross-sections.

The milk supply of our country, in one form or another, has been the subject of discussion year after year at Congress meetings. Its importance is an admitted fact, but, notwithstanding, I again venture to call attention to the matter. On this occasion, however, I do not propose to touch much of the ground already covered by former papers, but to consider the results of experiments and observations made while dealing with milk supply under the Sale of Food and Drugs Acts. For many years dairy regulations have been in force throughout the country which deal with the construction of floors and walls, and with lighting and ventilation. The owners of dairy farms in many parts of Scotland have spent large sums of money in improving their farms. Indeed, some enthusiasts have gone the length of introducing a system of heating and mechanical means of ventilation. It is only reasonable to pause and consider the practical results of these improvements, and to discover who are reaping the benefits from a milk supply standpoint. Do the owners of dairy farms receive anything like a fair return for their capital outlay? No. It is a well‐known fact that rents are on the down grade. Is the farmer of to‐day in a better financial position than formerly? No. He will tell you that the working of a “modern dairy” is more expensive than in the old steading, and that there is less flow of milk from the cows in the large airy byre than in the small old “biggin.” The price of milk is considerably less than it was fifteen or twenty years ago. At that time it ranged from 10d. to 1s. per gallon, and it is well known to you that hundreds of gallons of milk are now sent into our large cities for at least a distance of 100 miles, carriage paid, at 7½d. per gallon. In some cases the price is 9d. per gallon during the winter and 7½d. in summer. A farmer I know has a contract with a dairyman to supply him with 20 gallons of sweet milk, 16 gallons of skim milk, and 4 gallons of cream every day at an average rate of 7½d. per gallon all the year round. I have proved, by having test samples taken of the sweet milk, that it contains an average fat of 4.89 per cent. in 16 gallons. Neither the owner nor occupier of the farm can be any better off so long as such small prices prevail. Does the profit then come to the consumer? It does not.

THIS is the time of the year when, with the strong opening of the Spring publishing season, librarians take a review of matters which definitely concern books. There is a cant saying amongst certain eager librarians that their colleagues are too concerned with technical matters and too little, if at all, concerned with books. There may have been isolated cases of this kind, but it is merely untrue to say that the average librarian is not concerned, deeply and continuously, with the literary activity of his day. It is well that men should live in their own time and be thoroughly interested in the work of new writers. There is danger that exclusive occupation with them may lead to an unbalanced view of the book world. If one judged from the criticisms that occasionally appear in our contemporaries, one would suppose that the only books that mattered were the authentic fiction of the day, and by authentic is meant the books which go beyond average contemporary thought and conventions. Librarianship, however, is concerned with all books of all subjects and of all time. This note is merely a prelude to a number of THE LIBRARY WORLD which deals mainly with literature and with reading. Here we return again to the perennial fiction question.

NEXT TO banking, we are informed, Business Consultancy is the most favoured profession for graduates in the United States and it is likely, as in so much else, that here in Britain the same trend will be followed. It follows, as the famous query in a one‐time quiz member put it, that ‘it all depends on what you mean by Business Consultancy’.

This review paper seeks to enhance knowledge of how pre-loading affects reinforced concrete (RC) beams under fire. It investigates key factors like deflection and load capacity to understand pre-loading's role in replicating RC beams' actual responses to fire, aiming to improve fire testing protocols and structural fire engineering design.

This review systematically aggregates data from existing literature on the fire response of RC beams, comparing scenarios with (WP) and without pre-loading (WOP). Through statistical tools like the two-tailed t-test and Mann–Whitney U-test, it assesses deflection extremes. The study further examines structural responses, including flexural and shear behavior, ultimate load capacity, post-yield behavior, stiffness degradation and failure modes. The approach concludes with a statistical forecast of ideal pre-load levels to elevate experimental precision and enhance fire safety standards.

The review concludes that pre-loading profoundly affects the fire response of RC beams, suggesting a 35%–65% structural capacity range for realistic simulations. The review also recommended the initial crack load as an alternative metric for determining the pre-loading impact. Crucially, it highlights that pre-loading not only influences the fire response but also significantly alters the overall structural behavior of the RC beams.

The review advances structural fire engineering with an in-depth analysis of pre-loading's impact on RC beams during fire exposure, establishing a validated pre-load range through thorough statistical analysis and examination of previous research. It refines experimental methodologies and structural design accuracy, ultimately bolstering fire safety protocols.

The preliminary figures for the production of fruit in the United States of America for the year 1930 issued by the Department of Commerce, Washington, are as follows:—Apples, 163,543,000 bushel; grapes, 2,368,557 tons; peaches, 53,286,000 bushel; pears, 25,703,000 bushel; strawberries, 59,996,000 quarts; cranberries, 570,000 barrels. Assuming the bushel to be equal to fifty pounds weight (Av.), the weights of apples, peaches and pears produced are 3,650,000 tons, 1,189,000 tons, 574,000 tons respectively. The Department of Commerce has no means of intimating the proportions of fruits used for the raw, canning and preserve markets. The production of canned fruits is, however, high in the United States, a much larger proportion of the total crop of fruit being used for this purpose than is the case in this country. In the United States the fruit that is preserved is marketed either as jam, the fruit for this purpose being more or less in the form of pulp; or as preserved fruit when the fruit is whole or unbroken; or as fruit butter, which is fruit juice and fruit pulp evaporated till they form a semi‐solid homogeneous mass with or without the addition of sugar, spices, or vinegar; or as fruit jelly, which is the juice or water extract of fruit concentrated to a suitable consistency with the addition of sugar. In 1929, according to the Bureau of Census figures, the total value of the four products above named amounted to $44,073,809, or in round figures about £9,000,000. It appears that some two hundred firms are mainly engaged in the manufacture of these, a small and unknown amount being made as a kind of side line by certain wholesale grocers. It may be observed that (1) the fruit used is home grown; (2) the product, whether it be preserved fruit, jam, fruit butter or fruit jelly, has to be made in accordance with Federal or State definitions of these products; (3) the label on the pot or tin must truly describe the contents as to nature, quality and quantity; (4) that misleading statements or designs on such labels are forbidden by law. At the request of the National Preservers' Association the Bureau of Foreign and Domestic Commerce recently completed a survey of the preserving industry. The results are incomplete, as many firms did not make returns, but the figures obtained would appear to cover about 40 per cent. of those relating to the industry for the year 1929. These figures are at least useful for comparative purposes, and multiplication by 2½ is probably justifiable under the circumstances as affording some guide to the total amount. Thus the actual figures obtained by the Department for production by “major classification” are as follows:—Preserves and jams, 62,490,389 lbs.; jellies, 32,301,654 lbs.; fruit butters, 40,019,560 lbs.; citrus marmalade, 1,849,104 lbs. Total, 136,660,707 lbs. This total when multiplied by 2½ shows that something over 150,000 tons, of 2,240 lbs. to the ton, of the products mentioned above were made in 1929. If the population of the United States be 125 millions, it is certainly near that figure, the output is low compared with the output in this country; for preserves and jams very low. The deficiency in this item is offset by the high percentage compared with our figures of fruit jelly (235), and of fruit butters (30) produced. Much fruit grown in the United States is, however, absorbed by the canning industry which has been long established and has reached enormous dimensions; and also in the production of fruit juices as beverages. Again, anything but a numerical comparison, even if that be directly permissible, is to our disadvantage. For while the fruit grower in the United States finds a ready market for his crops in the markets for jam and its associated products, our fruit growers would seem to receive no such measure of encouragement from our jam makers, who purchase large quantities of cheap imported fruit pulp of questionable wholesomeness in many cases. As to the quality of the material it is safe to say that much of the jam made in the country at the present time would be refused entry into the United States. As to the kind of jam and preserve made in the United States, there are three kinds: Standard, Compound, and Imitation. In round figures 75 per cent. of the jam is of standard grade, 19 per cent. is compound, and 6 per cent. imitation. For jellies the figures are: 45·45 per cent. standard, 27 per cent. pectin and apple base, imitation 27 per cent. As to the kinds of fruit used in making jam, strawberry jam heads the list with 39 per cent. of the total; raspberry with 19 per cent. No other percentages run into double figures. The next highest is peach 8·74 per cent., the lowest is gooseberry 0·13 per cent. 78·5 per cent. by weight of the strawberry jam is of standard quality, 19 per cent. compound, 2·3 imitation; 75·5 per cent. of the raspberry jam is standard, 21 per cent. compound, 1·6 imitation. The average invoice values of these jams are as follows:—Standard strawberry jam, 17.64 cents per lb., say 9d. per lb.; compound strawberry, 7d.; imitation strawberry, 5d. The corresponding figures for raspberry being 7½d., 6½d., 5¼d. These figures being about the average invoice prices for all kinds of jams of the three qualities named. From these figures it would appear that it is possible in the United States to market strawberry and raspberry jam of a nature conforming to Dr. Johnson's definition at a fairly low price. In the United States of America there are two laws which govern the purity of the food supply. One is the Federal Law of 30th June, 1906. The Federal Law applies to the Federal District of Columbia and to Inter‐State Commerce, that is to say to goods which may be sent from one State of the Union to another State of the Union. The other laws are the State laws which have been passed by the legislatures of the various States. Before these laws were passed, manufacturers of adulterated food products were at liberty to make and sell such products in their State. These State laws are applicable only to the particular States for which they have been passed. As a general rule they are founded on the Federal Law or follow the wording of this law closely as a matter of expediency, but the various States responsible for these enactments are not bound in any way by the wording of the Federal enactments. The State Laws, however, are complementary to the Federal Law. The power of a State to protect itself against the ill‐effects of unsatisfactory food products manufactured in another and imported within its boundaries is extremely limited. This is a matter for the Federal authorities in the enforcement of the Federal Law. On the other hand the Federal Law has no power over goods manufactured in any given State for sale in that State. It is only when such goods pass from one State to another and thus become part of Inter‐State Commerce that the Federal Law has authority. Nevertheless the Federal and State officials are in close co‐operation, and a network of protective legislation covers the United States, and the laws and regulations are administered by keen and experienced legal and technical officers.