Unconfined Compressive Strength Characteristics of Overboulder Asbuton and Zeolite Stabilized Soft Soil

Abstract

Soft soil was one of the most widely encountered problems in construction, especially for archipelago countries which most of its area was lowland with a high deposit of soft soil. To overcome this problem, soil stabilization was one of the most widely used as a solution. Soil stabilization in general uses chemical substances that are classified as pozzolan material. Pozzolan material uses its capability to strengthen the cohesion of soil grains. Mostly, pozzolan material consists of silica. Overboulder asbuton and zeolite were examples of natural pozzolan material in Indonesia. Both materials have a high silica content. Thus, the author interested to figure out the mechanical behavior of these two substances as a soil stabilizer. This research was a correlating study to the previous paper with the same author which discusses the overboulder asbuton as a soil stabilizer. Overboulder added to the mix is determined as 15%, with varied zeolite percentages applied to examine the differences. The UCT was conducted according to ASTM D-2166 as a parameter. As the standard remolding method, a standard proctor test was conducted to determine the optimum moisture content and the maximum density of each mix. While the UCT specimens were tested at the certain curing time for each composition. The curing time applied was 0, 7, 14, and 28 days. By this curing period, the effective pozzolanic reaction that occurs for each composition could be determined. The result shows that zeolite addition to overboulder asbuton could increase the soil density and increase its compressive strength. It is indicated that overboulder asbuton and zeolite mix could be a proper alternative as a soil stabilizer. Doi: 10.28991/cej-2021-03091635 Full Text: PDF

Effect of Specimens’ Height to Diameter Ratio on Unconfined Compressive Strength of Cohesive Soil

“…The strain rate of the unconfined compression testing was adopted according to earlier studies [1,16]. The strain rate was taken at 1% per minute as stated in the Japanese geotechnical standard [5] for all specimen heights to decrease the strain rate effect on the unconfined compression test result.…”

“…The H/D ratio of the unconfined compression soil test differs in different institutional manuals and design codes. According to the ASTM D2166 [4] standard, the H/D ratio of the cylindrical sample specimen is recommended to be between 2.00 and 2.50, with a diameter greater than 33 mm [5][6]. A British standard method of soil testing (BSI 1377-7) [7] employs an H/D ratio of 2.0, with a diameter ranging from 35 to 100 mm [8].…”

Experimental and Numerical Study on the Composite Column Behavior: Loess Soil Reinforced by Concrete-Stone Column

“…The reading of load cell and earth pressure gauges was taken through data-acquisition systems connected to the computer. A constant loading rate of 1 mm/minute was applied [32,33]. The loading was kept steady for half an hour until the settlement reached 30 mm.…”