Thursday, 20 December 2018

Loess & Society: the Indus Valley civilizations ~3000 BCE - 1500 BCE.

The Chinese society grew, developed and flourished in the loess regions associated with the eastern parts of High Asia. This was/is the most impressive and longest lasting of the ancient civilizations and it can be argued that it owes much of its success to its firm foundation in the loess lands. There were/are loess lands associated with the western end of High Asia; not so spectacular and amazing as the Chinese occurrences but significant and deserving of appreciation. The Central Asian loess has been studied and investigated but the loess now in India and Pakistan has been neglected and its societal influence has not been fully appreciated. The Indus Valley was the home for well developed societies in the period of around 3000-1500 BCE; two centres are identified: Harappa and Mohenjo Daro and they both appear to have interesting loessic connections. Here were well developed societies with brick buildings, built with fired bricks, and an alphabet or writing system, which still needs to be significantly translated.

Some of these symbols appear to have geomorphological significance. There are four major rivers in the Punjab- the Jhelum, Chenab, Ravi & Sutlej dominate the region, and are closely associated with the Harappan society. The better known Mohenjo Daro situation is located further down the Indus Valley. The loess deposits in the Indus Valley are not well demarcated; there has not been much mapping activity, but the two deposits indicated by S.Z.Rozycki correspond nicely with the two sites of ancient societies

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Region 7 on the High Asia diagram is where we find the Indus Valley civilizations; region 1 is the Central Asian loess region; the two rivers indicated are the Amu-Darya and the Syr-Darya. Regions 3 & 4 contain the Chinese loess deposits.

S.Z.Rozycki  1991.  Loess and Loess-like Deposits. Ossolinium Wroclaw. On p.117 in the section on Local Loesses of Southern Asia - one of the very few maps of loess in India region. SZR has made the picture rather too complex but he manages to show the two loess regions: NE of the Thar desert and W of the Thar desert; the locations of the Harappan and Mohenjo-Daro civilizations.

 Bricks. Thoughts about bricks. The Indus Valley people built with fired bricks; and they built extensively- there was a lot of brick construction in Harappa and Mohenjo Daro. So they must have had good access to large deposits of suitable brickearth- the sort of brickearth that encouraged the making of fired bricks. It has been suggested that the location of early brick buildings in England was to some extent controlled by access to loessic brickearth- for the construction of suitable bricks. Similar constraints could apply in the Indus Valley; city location may depend on the provision of material for making bricks. In the case of Mohenjo Daro the city appears to be placed exactly on the loess region demarcated by Rozycki. A large patch of suitable loess providing building material for a substantial city. And there must have been plenty of wood available; we see the bricks being fired in clamps with wood as the fuel. A lot of bricks requires a lot of wood.

The bricks were made to a 4:2:1 ratio; the sizes were 10 x 20 x 40cms or 7 x 14 x 28 cms. These are large bricks; the smaller bricks appear to been used in houses and the larger bricks in public buildings. They were well laid and many of the constructions have lasted remarkably well.


The question of the big brick.
Reports suggest that fired bricks were used to construct the buildings at Harappa and Mohenjo Daro. Also it is suggested that some of these were very large- the big bricks 10 x 20 x 40 cms; far too large to be conveniently handled. The normal European brick in the 21st Century has dimensions of about 6 x 10 x 21 cm. It is designed to fit the hand of the bricklayer, and also be of a weight which he or she can lift and manipulate.
To be able to produce, to move, and to construct with these large bricks suggests a very well organised and efficient society. The number of bricks used in Harappa and Mohenjo Daro is enormous- so vast brickearth resources were required, and large amounts of fuel for firing. But it is the size of the large brick which causes questions. It is too big; it requires two people to handle it- particularly in the unfired state; great skill and dexterity would have been required. And to get satisfactory firing.. difficult.


Are the reports perhaps mistaken? The reported smaller Indus Valley brick at 7 x 14 x 28 cm is not that much larger than the standard European brick and would seem to have been a logical size for normal use. We need a brick measuring expedition to the Indus Valley to measure the bricks, and try
to locate the regions where they were produced.

Tuesday, 4 December 2018

Four Soviet Loess Laboratories

The Soviet Union was dismantled in 1990 and a widespread network of loess investigation and loess research vanished with it. In 1988, very close to the end of the Soviet period M.Yu.Abelev, a senior investigator, addressed a conference in Beijing, on loess in the USSR. He described the world of loess geotechnology, probably unaware that the end-times were so close. He recorded that 30,000 people in the USSR were concerned with the problems of research into the properties of loess and the development of methods of construction on loess soils. This seems like an incredibly large number but, back in 1988, there was a large amount of loess territory under Soviet control.

Abelev listed some interesting geography: loess soils constituted more than 14% of the total territory of the USSR. Such soils were widely spread over the territory of the whole Soviet Union to the south of the 60N latitude. They occupied more than 80% of the territory of many of the union republics such as the Uzbek SSR, Tadzhik SSR, Kirghiz SSR, Ukrainian SSR, Moldovian SSR and Azerbaijan SSR. Loess soils were also encountered in the Georgian SSR, Kazakh SSR and in quite a few regions of the RSFSR. A great many residential buildings in cities and towns and big industrial enterprises were being erected on loess. In many buildings and structures erected in the 1920s and 1930s deformations developed and failures sometimes occurred. Post- 1930 in the USSR under the supervision of Professor Yu.M.Abelev (1897-1971; father of M.Yu.Abelev) special research laboratories and production institutes were founded which were concerned with the research and development into reliable methods of construction of industrial and civil structures on loess ground.
New laboratories concerned with investigations into the properties of loess were set up in Kiev, Tashkent, Baku and Dnepropetrovsk; the four Soviet Loess Laboratories. Now, 30 years after Abelev delivered his paper, the quondam-loess of the USSR is in separate new countries and the all union loess network is broken.

2 references
Abelev, Yu.M. ,Abelev, M.Yu. 1968.  Fundamentals of design and construction on collapsible marcoporous ground.  Izdatel'stvo Literatury po Stroitel'stvu, Moscow 2nd.ed (this 2nd edition is probably better than the 1979 3rd edition- certainly cartographically).
Abelev, M.Yu.  1988/1989.  Loess and its engineering problems in the USSR. in Engineering Problems of Regional Soils (International Conference Beijing 1988) ed.CCES, Pergamon Press, Oxford, pp.3-6

Some additional material from V.I.Krutov:
[Krutov, V.I.  1987.  Foundation construction on collapsible soils. Soil Mechanics & Foundation Engineering 24, 219-223.]

Collapsible soils ~10% USSR territory; recent (1989) construction 30%- in the regions intense construction activity.  Problems arose in the 1920s with irrigation systems in Central Asia and the North Caucasus, and oil industry construction at Grozny.  Then the first 5 year plans, large metallurgical and machine manufacturing plants in Zaporozhe, Nikopol, Dneproptetrovsk, Zhadanov, Kherson and Kuznetsk, also irrigation systems and hydraulic structures in Central Asia, the N. Caucasus, & Transcaucasia.

Post-war years: largest industrial structuresd: VAZ, KamAZ, Atommash, KZTE etc.  Residential and industrial construction in Ukraine, the Rostov region, Siberia & Central Asia,

First solutions to foundation problems by Yu.M. Abelev (1931). Later contributions from M.Yu. Abelev, V.P. Anan'ev, Kh.A. Askarov, L.G. Balaev, Ya.D. Gil'man, V.N. Golubkov, M.N. Goldstein, A.A. Grigoriyan, N.Ya. Denisov, S.N. Klepikov, A.A. Kirilov, N.I. Kriger, A.K. Larionov, I.M. Litvinov, G.M. Lomize, G.A. Mavlyanov, A.A. Musaelyan, A.A. Mustafaev, N.A. Ostashev, A.L. Rubinshtein, E.M. Sergeev, V.E. Sokolovich, R.A. Tokar' & N.A. Tsytovich.

afterword from Osipov & Sokolov
[Osipov, V.I., Sokolov, V.N. 1995.  Factors & mechanism of loess collapse. in Genesis & Properties of Collapsible Soils. ed. E.Derbyshire, T.Dijkstra & I.J.Smalley. NATO ASI series 468, Kluwer]

55 cities & towns in Russian regions affected by loess collapse; 3.5 million km2 in area. They list 6 relevant books:

Anan'ev, V.P. 1964. Mineralogical composition and loessial soils properties. RGU Rostov-on-Don 218p.

Balaev, L.G., Tsaryev, P.V. 1964.  Loessial soils of Central & Eastern Pre-Caucasus area. Nauka Moscow 248p.

Kriger, N.I.  1965.  Loess, its properties & relation to the geohgraphical environment.  Nauka Moscow 296p.

Krutov, V.I. 1982.  Bases and foundations on collapsible soils. Budivel'nik Kiev.

Larionov, A.K. 1971.  Research methods of soil structures.  Nedra Moscow 168p.

Sergeev, E.M., Larionov, A.N., Komissarova, N.N. eds.  1986.  Loess in the USSR.