对于DryStudy试述on试述Maximum试述Dry试述Density试述of试述Aeolian试述Sand试述for试述Roadbed

论文导读：tiontesttodeterminetheirrationalityinmaximumdrydensityofAeoliansand.Dryvibratingmethodcompactingtest,counterweight-addeddryvibratingmethodcompactingtest,andcounterweight-addedwater-saturatedvibratingmethodcompactingtestwererespectivelygiventosamplesofAeoliansand
Abstract: The analysis adopted the earthy conventional compaction test to determine the irrationality in maximum dry density of Aeolian sand. Dry vibrating method compacting test, counterweight-added dry vibrating method compacting test, and counterweight-added water-saturated vibrating method compacting test were respectively given to samples of Aeolian sand. With the analysis of test data, advantages, disadvantages and applicability of each test method were summarized. A conclusion was drawn that counterweight-added water-saturated vibrating method compacting test was applicable to determine maximum dry density of Aeolian sand.
Key words: roadbed construction; Aeolian sand; maximum dry density; vibration; water-saturated; counterweight-added


Vast deserts exist in Northwest China. With the development and construction of the West, road construction in desert regions has been in full swing. Road materials in desert regions are mainly Aeolian sand. There is no a complete set of standards facilitating the implementation for determination of maximum dry density of Aeolian sand in current specificatio源于：论文发表网www.7ctime.com
ns, so it becomes an issue puzzled the construction unit during the construction. Following are several test methods to determine maximum dry density of Aeolian sand. With reference to actual site construction conditions, a test method most suitable for use is selected.
1. Earthy standard compaction test not suitable for Aeolian sand
The standard compaction method is used to provide compaction test for the 3 groups of Aeolian sand samples. Fig. 1 shows test results.
Fig.1 Relation between Dry Density and Vibrating Time (Standard Compaction Method)
Much is obtained from analysis of above test results:
1)Whe论文导读：tomeetqualityrequirementsoffixedandevenshapewhichincreaseswiththeincreaseofreactivepower.2)Duringrepeatedparalleltests,discretenessoftestresultisratherhigh.Thereisnoastableunitqualityindex.3)Duringthechangeofwatercontent,twopealvaluesoccurindensi
n water content increases, spraying sand results in waste of reactive power due to liquefaction of sand sample surface. Several tests demonstrate its compaction curve fails to meet quality requirements of fixed and even shape which increases with the increase of reactive power.
2)During repeated parallel tests, discreteness of test result is rather high. There is no a stable unit quality index.
3)During the change of water content, two peal values occur in density. Dry peak value is greater than the peak value of water content and is completely different from earthy peak value. This shows properties of sand and earth differ. It also shows sand density is not in close relation to water content. Thus, it fails to meet requirements of density standard which is used as the standard reference and complies with engineering requirements.

2. Dry vibrating compacting test

It is common sense in production and living of the public in desert regions that Aeolian sand compacts due to the vibration inside the vessel. According to documents of Yulin Road Administration Bureau, resonance frequency of Aeolian sand is 25-55 Hz. The frequency increases as the density increases. A 1m × 1m concrete vibrating table is used in the test. Amplitude of vibrating table is adjusted to 0.3mm; vibrating frequency is 47.7 Hz. The vessel is a big barrel for standard compaction test. Its volume is 3,085 cm3.