Homes evacuated in San Antonio as hill crumbles

Link

Well I am glad no one got hurt. Could be something that has to do with the faults?

SAN ANTONIO – Construction crews moved dirt to shore up a group of houses precariously perched on a crumbling hill in San Antonio on Monday as engineers tried to determine why the land below was shifting, causing dozens of homes to evacuate.

[edit on 25-1-2010 by capgirl]

reply to post by capgirl


Something similar happened in the Atlanta area not long ago, shoddy work rather than a natural occurance. Homes were cracking up, sliding downhill, just like in this case, reports of pure residential building garbage being used as landfill, leaves the ground wide open to the ravages of erosion.

reply to post by space cadet


Are you saying that landfills can do that? wow I did not know that! Seriously....Maybe that was the case then? Maybe the media is hiding it so there wouldn't be a protest or something.

reply to post by capgirl


Actually what I meant was that the homes in the Atlanta area were built on essensially a bunch of garbage, because the graded land has passed inspection even though it had been filled with waste from the homes being built there. It wasn't a legal landfill. In San Antonio they are saying the building permit was not issued. I suppose it is possible that it was not issued to build the retainer wall due to the risk of collapse, or shoddy grading, whatever reason, they did not allow a permit.

reply to post by space cadet


Ohhhh ok I got ya now

From what I read in the article, it sounds like the area was filled because there was crumbling problems before. Also the area was too steep to build, therefore they probably did extensive fill work.

I have been a construction supervisor for several years. In construction for many more.

I see more in the photo then the article. When filling an area, a specific fill material must be used to create a stable base. The fill is laid in lifts of specific height and compaction tests are done to ensure correct compaction results. These stats are determined by an engineer to determine proper soil results.

That being said, from the picture it looks like the cause is either the soil conditions that existed before the fill was placed or the fill was placed improperly. Moisture of the fill material must be maintained to a certain percentage. To me, this looks exactly like some trenches we had problems with back in Fresno, the last place I was building. When the soil moisture is incorrect and you get rain or even landscape water on incorrect moisture content, the result is exactly what I see in the photo.

Also any retaining wall over a certain height (I think 12") must be designed by an engineer.

As for the city saying the permit for the retaining wall was not issued, this is total bull on the cities part. You cannot even have anyone move into a building until ALL components of a site are complete.

It is called a Safe to Occupy clearance. Everything necessary for move in, is required to be complete, including what is called a site inspection. The Fire Dept, City Plumbing and Water, City Building Inspector, City encroachment inspector among others need to verify all requirements are complete.

2 possibilities. Fill placement or the original soil problems. Or the failure of the retaining wall.

Roderick Sanchez, the city's planning and development director, said the builder built the retaining wall without a permit. The city was still waiting for verification that the wall was designed by a certified engineer and built to specifications, Sanchez said.

This right here sounds like the standard CYA (cover your ***) statement from the city.

It also could be a natural occurrence of movement of groundwater or other geological manifestations.

You will need a geologist or a soils engineer to make that call though.

[edit on 1/25/2010 by endisnighe]