Problem 3 Based On Index Properties of Soil - Three Phase System - Soil Mechanics

TL;DR

This analysis discusses three level 3 problems involving the determination of maximum and minimum void ratio, reduction in porosity after adding different soil compositions, and calculation of shrinkage limit and shrinkage ratio.

Transcript

so we'll start with the level three problems the statement of the problem is as follows before the sandy soil which has the spherical variant shape when which is a uniform in nature that means all particles are spherical in shape and all have the equal diameters so in this case you're asked to determine the maximum and minimum void ratio so you hav... Read More

Key Insights

• 🥳 The arrangement of soil particles and their size determine the maximum and minimum void ratios in sandy soil.
• 🥪 The addition of dry sand and silt to a subgrade soil reduces its porosity.
• ⛔ The shrinkage limit can be calculated by analyzing the decrease in volume when the soil is dried from its liquid or plastic limit.
• 🫥 The shrinkage ratio indicates the soil's shrinkage potential and can be determined by dividing the slope of the shrinkage line by the dry volume of the soil.

Questions & Answers

Q: How do you calculate the maximum and minimum void ratios in sandy soil with spherical particles?

The maximum void ratio can be calculated using the formula 6π/PI - 1. The minimum void ratio is typically 0.35 for sandy soil.

Q: What happens to the porosity of a soil after adding dry sand and silt?

The addition of dry sand and silt reduces the porosity of the soil. The porosity can be calculated by dividing the volume of voids by the total volume.

Q: How do you calculate the shrinkage limit of a soil?

The shrinkage limit is determined by analyzing the decrease in volume when the soil is dried from its liquid or plastic limit. The shrinkage limit is typically expressed as a percentage.

Q: What is the shrinkage ratio and how is it calculated?

The shrinkage ratio is the slope of the shrinkage line divided by the dry volume of the soil. It provides a measure of the soil's shrinkage potential.

Summary & Key Takeaways

• The analysis discusses the determination of maximum and minimum void ratio in sandy soil with spherical particles. It provides formulas and explanations for calculating void ratios based on different particle arrangements.

• The analysis also explores the reduction in porosity after adding dry sand and silt to a subgrade soil. It explains how to calculate the new porosity and the decrease in porosity.

• Lastly, the analysis addresses the calculation of the shrinkage limit and shrinkage ratio based on the decrease in volume at different soil states.