Fatima Al Zahraa Olleik

Thank you Sohaib and Ayesha for your quick response, The wall will be connected to the raft at both edges, so the sliding and overturning must not form a problem here. I calculated the earth pressure due to the surcharge, and checked the moments they induced, wall section and steel provided is adequate. I will check with the geotechnical engineer about the cyclopean concrete used, and the calculations I made. Thank you both for your help.

Sorry for being late Ayesha, here is a drawing of one of the cases: RAFT OVER EXISTING WALL.pdf DETAIL A.pdf

Dear fellow engineers, In a refugee camp reconstruction, we have the following dilemma: First, we have an existing retaining wall, height up to 4.5 meters, thickness ranging from 0.25 to 0.4 m. On the back of the wall we have existing an layer of cyclopean concrete :height up to 4.5, width 3m, and length along the wall. A 5 story building is to be built over the cyclopean concrete. This means that the Raft of the building (0.5m thick) will lie directly above the existing wall. The question is, what is the calculation required to ensure that this wall will withstand the loads of the raft?

Thanks a lot Engr Uzair , I'l do that and take the most critical case.

Thanks for replying Engr Uzair, the buildings are 18 m high which is relatively low. I modeled the whole thing in one ETABS model ( All buildings together) but did not use the multiple tower option. Then I also modeled all associated Raft Foundations in one model on SAFE. Afterwards, I modeled each Set of Buildings (on one Raft) in Separate models. The results varied with respect to steel reinforcement (in some places). The additional question is Is the software generating moments from set of buildings X on the Raft of set of buildings Y?

Salam Alaykom All, I am modeling a refugee camp on Etabs. I have over 20 buildings to be modeled, each 5 share the same raft foundation , and each raft foundation is no more than 3 meters away from the other. For simplicity I modeled all 20 buildings in the same Etabs Model to Calculate the forces on the raft foundations. My question is : 1_ Will the Raft Foundations be Affected by each other , knowing that the buildings they support arent connected in any way?