I M

1. Under what conditions can soils be chemically stabilized?

Stabilization of soils can be achieved by the addition of lime or cement. Cement is added to the soil to improve strength and durability. Because development of strength begins as soon as water and cement are mixed, construction with soil-cement must be done according to a carefully controlled schedule. Construction with soil-cement may be done by a batch process or a mix in place process. Lime is an effective stabilizing agent for fine soils with high plasticity. The addition of quicklime or hydrated lime results in both a cementing action and an alteration of the physical chemistry of the soil-water system. The calcium in the lime reacts with available silicas in the soil to produce cement, which increases strength.

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2. What errors can occur in density testing?

*Liquid volume measurement.

*Irregular solid volume.

*Temperature affects the density.

*The final source of error is measurement of mass.

Respond

3. What errors can occur in measuring percent compaction?

Soil compaction is process by which stresses are applied on soil which causes densification as air is displaced from the pores between soil grains.

The errors that occur in measuring percent compaction are dry unit weight of soil measurement, loss of moisture, wrong counting number of blows, maximum dry density of soil, digital balance used to weigh soil, and finally errors due to wind and pressure change. In addition, when zeroing the digital balance, a slight wind or pressure change may make the value change from zero.

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J R

2.

What errors can occur in density testing?

Precision and accuracy can be affected by the type of instruments used to measure liquid volume.

Irregular shapes of an object can be difficult to calculate.

Permeable objects can skew volume measurements.

Measurements of mass can vary with the type of scale being used. An uncertainty value can be considered to determine the reliability of the measurement.

Temperature changes can cause density errors.

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3. What errors can occur in measuring percent compaction?

Errors can occur when measuring the weights of the samples and/or the values were not read correctly.

A loss of moisture content when transported or stored.

Digital balances can affect the measurements.

Counting the wrong number of blows when compacting could cause errors.

Respond
 

4. What must a contractor do if soil is placed and cannot be compacted to required levels?

It can indicate there is an excess or lack of water, soil or elevation. If the soil is too wet, contractor must allow soil to be aerated or mixed with dryer materials or add water if too dry. Also, the need to perform density tests from the proctor to the soil being compacted. Identify the proper compaction equipment for the soil type he/she is compacting, whether it be cohesive or granular soils.

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D G

1. Under what conditions can soils be chemically stabilized?

Soils can be chemically stabilized when there is a low strength of soil and it is being improved. Another condition when an individual is trying to improve the soil strength such as durability. By trying to improve the soil properties. When lime or any other chemical is used to alter the properties, the soil has been chemically stabilized.

Respond

2.   What errors can occur in density testing?

Some errors that can occur during density testing can be the temperature. Temperature will affect density. Another error that can occur is the measurement of mass or an irregular measurement of volume.

Respond

3.   What errors can occur in measuring percent compaction?

Soil compaction will stress the soil as air is displaced from the pores between the soil grains. Errors that can occur is loss of moisture, incorrect number of blows, or errors due to the wind and pressure change.  

Respond

I M

1.

Under what conditions can soils be chemically stabilized?

Stabilization of soils can be achieved by the addition of lime or
cement. Cement is added to the soil
to improve strength and durability. Because development of strength begins as soon as water and
cement are mixed, construction with soil
–
cement must be done according to a carefully controlled
schedule. Construction w
ith soil
–
cement may be done by a batch process or a mix in place process.
Lime is an effective stabilizing agent for fine soils with high plasticity. The addition of quicklime or
hydrated lime results in both a cementing action and an alteration of the p
hysical chemistry of the
soil
–
water system. The calcium in the lime reacts with available silicas in the soil to produce cement,
which increases strength.

Respond

2.
What errors can occur in density testing?

*Liquid volume measurement.

*Irregular solid volume.

*Temperature affects the density.

*The final source of error is measurement of mass.

Respond

3. What errors can occur in measuring percent compaction?

Soil compaction is process by which stresses are applied on soil which causes densification as air is
displa
ced from the pores between soil grains.

The errors that occur in measuring percent compaction are dry unit weight of soil measurement, loss of
moisture, wrong counting number of blows, maximum dry density of soil, digital balance used to weigh
soil, and
finally errors due to wind and pressure change. In addition, when zeroing the digital balance, a
slight wind or pressure change may make the value change from zero.

Respond

I M
1. Under what conditions can soils be chemically stabilized?
Stabilization of soils can be achieved by the addition of lime or cement. Cement is added to the soil
to improve strength and durability. Because development of strength begins as soon as water and
cement are mixed, construction with soil-cement must be done according to a carefully controlled
schedule. Construction with soil-cement may be done by a batch process or a mix in place process.
Lime is an effective stabilizing agent for fine soils with high plasticity. The addition of quicklime or
hydrated lime results in both a cementing action and an alteration of the physical chemistry of the
soil-water system. The calcium in the lime reacts with available silicas in the soil to produce cement,
which increases strength.
Respond

2. What errors can occur in density testing?

*Liquid volume measurement.

*Irregular solid volume.

*Temperature affects the density.

*The final source of error is measurement of mass.
Respond

3. What errors can occur in measuring percent compaction?
Soil compaction is process by which stresses are applied on soil which causes densification as air is
displaced from the pores between soil grains.
The errors that occur in measuring percent compaction are dry unit weight of soil measurement, loss of
moisture, wrong counting number of blows, maximum dry density of soil, digital balance used to weigh
soil, and finally errors due to wind and pressure change. In addition, when zeroing the digital balance, a
slight wind or pressure change may make the value change from zero.
Respond