If I recall my geotechnical history, piles were loaded to 2X design load, not simply to provide a safety factor of 2 but to statistically assure that all production piles have a very high degree of certainty of having a capacity at or exceeding the design load.
If a pile load test is considered...
Many years ago I was involved with the construction of a new bulkhead in Vancouver. The bulkhead was backfilled with silty sand and was compacted using a vibratory Terraprobe.
Also, always remember first principles. The lateral stress at any location or depth is equal to the vertical effective stress multiplied by the appropriate pressure coefficient. When calculating the vertical effective stress, you must use the ACTUAL anticipated pore pressures. Since the...
I agree, all of your points are valid and must be considered in the final design. But is there any reference or published method that combines the two dissimilar supports - the passive soil pressure developed on the sheetpiles below the streambed and the lateral capacity of the gravity...
In my opinion, rock sockets need only be large enough to fit the pile assuming the necessary vertical and lateral capacity are provided. Any size concrete-filled hole large enough to fit the pile will provide sufficient concrete cover over the faces of the flanges and web for corrosion protection.
My client needs to create a temporary sheet pile diversion wall down the middle of river. The sheet pile diversion wall needs to resist about 5 feet of water at normal flow and about 11 feet of water at design flood stage. The sheets will be driven to bedrock to provide a cut-off through the...
In top-down construction, each floor level is cast on-grade then the soil below is mined out to get down to the next lower level. I am assuming the temporary anchors provide stability of the wall at that next lower level until the slab and/or floor beams are constructed at that level. Once the...
One point that is missing from the discussion is the fact that the anchors are being used in top-down construction. I'm assuming that once the permanent supports (eithier the full slab or just the permanent building beams) are in place, any given level of tiebacks is redundant and could (but...
I agree with TXStructural on this. I've used nuts on the tops of micropile core bars to develop the full tension load of the pile within "relatively" thin pile caps or into grade beams. The same mechanics apply as given in ACI 318 for headed bars. The nuts produced for threadbars by all of...
Provided there is no movement of "fines" along with the water, the seepage should not be a structural concern. The filter fabric backing on the drain mat will prevent most migration of fines. However, it is dfficult to check whether the fines are migrating along with the water. If possible...
I have designed and constructed many permanent soil nail walls. Hairline cracks are very common in the permanent concrete facing. Assuming the reinforcing in the facing was designed per GEC 7, then I would expect some cracks. Assuming the reinforcing is designed correctly, it should be...
Consider using a slide rail shoring system. There are several manufactures of slide rails or similar systems. I prefer the slide rail system available in the US through United Rentals Trench Saftey.
A 75'x75' excavation will require many internal braces but since, I presume, most of the...
Thanks for the replies. The two existing industrial buildings both have basements and the footings of the new walls will be at about the same elevation as the existing footings. There will be no unbalanced earth pressure loads since.
Also the alleyway is the same length as both buildings -...
I have a project in an alleyway between two existing buildings. The alleyway is about 7 feet wide and both buildings have basements that go down about 20 feet. At both ends of the alleyway, a retaining wall must be constructed. The walls will be about 20 feet tall but only about 7 feet...
We always assume the axial load is dissipated into the sheetpile or soldier pile wall then into the soil. The walers must be welded to the walls, particularly near the ends of the wales. A free-body diagram of the wale and load path would show that the end reactions pass must pass through the...
The earth pressure(s) from the higher terraces applied to the lower level walls can be approximated as if they were an embankment. Influence diagrams for various geometries were derived by Perloff (1967)and can be found summarized in the "Foundation Engineering Handbook" edited by Winterkorn...
