Dear reader we have discussed some method to handle collapsible soil; in this part we will learn about some addition measure like providing deep foundation and checking moisture to penetrate foundation soil.
In choosing foundation systems if possible select deep foundation. It is the safest way but most costly method to mitigate foundation settlement in this type of soil. Replacing deposit of collapsible soil is considered cost effective when they remain in shallow depth. Otherwise replacing and flooding techniques both is not valid.
Deep foundation like piles can be rest on stratum below collapsible soil. Other foundation system like mat foundation or post tensioned foundation can also be designed to resist expected settlement in collapsible soil. Mat foundation is effective to reduce differential settlement. We have published many posts about design, construction and computer modeling of raft or mat foundation.
We know collapse in natural soil or fill of the same are triggered with the penetration of moisture. Now if we can check moisture to penetrate the triggering mechanism becomes inactive and foundation will remain safe against settlement.
The common sources of moisture infiltration are water from
• Leak in water supply line
• Breaking down of water supply or sewer line
• Ponding of rain water around or near foundation
• Any type of surface runoff
• Leaks in pools
So immediate repairing of any leak and break down in water or sewer line and providing effective drainage around building site to avoid ponding of rain water, in one word, all possible method providing moisture barrier will make your foundation and structure safe against collapsible soil.