Will there be any new technology where we can stabilize the foundation of existing structure aside from jet grouting procedures? especially in areas of limited space without affecting much the adjacent structures? please advise anyone thanks
Helical screw piles can be used to underpin. However, like anything else, you will have to determine if your situation allows this concept to be used. You may wish to solicit the views of a geotech engineer and screw pile contractor.
A bit more information on your particular problemmay be useful to obtain other ideas.
Its an existing school and we want to minimize the disruption of classes. The affected area is located at two corners of the bldg. which serves as classroom for the grade students. The access going to the area is 2m width door with a ht of 2.1m. The ceiling ht. is 3.5m
The equipments to be used is also a factor just wondering if the helical screw piles can best fit in the situation.
How much of the foundation has to be underpinned? You could do the work the old fashioned way by hand digging it in 4' wide sections and concreting it. It takes a little longer, but it is not particularly noisy.
bnard, there are many ways to underpin a structure besides jet grouting. A few of the ones that I have seen used: hand work (already noted), augered cast in place piles, screw anchors, pin piles (jacked into place), and drilled piers (installed from the outside and a needle beam placed under the corner).
Talk with the geotechnical engineer for the project, he/she should be able to give you a shorter list customized for the project.
bnard, GeoPaveTraffic mentions a variety of techniques to underpin. I'll add to his list with pressure grouted micropiles. Which method to use really depends on your given site conditions. Good Luck.