Reinforced Concrete Waffle Sandwich Floor Experimental And Theoretical Study

Because they are two -- way ribbed and with re1ative1y smal1 ribspacing, Reinforced concrete waff1 e s1abs exhi b it higher st if fness andsmaller deflections and behave we11 under 1oads. Because of theirarchitectura1 benefits for 1ower structura1 height and l ight weight aswe1l as economic benefits, they are best suited for 1arge span structuresas wel1 as tal1 bui1dings.However, this kind of structures have not been used wide1y fQr theircomp1ex ca1culate theory and the restrict ion of the forms. We developeda kind of waff1e s1abs with .f il1ings with the co1laboration of somecompany. With the he1p of the fi11ings, forms and concrete can be great1yreduced and hence speed up the process of construction. The fi1lings cana1so he1p the cei1ings to be f1at and at the same time he1p strengthenheat preservation as we11 as heat and sound insu1ation of the f1oor.Waff1e s1abs with fi l1 ings can be ca1cu1ated with same theory of thewaff1e slabs However, there sti11 have been few investigat'ions on thesestructures up to now, especia1ly on that of supported periphera1ly.Theory ana1yses are carried out in this thesis according to theexperimenta1 studies. Main works that have been done in this thesisinc 1 udi ng:1. Tests of a fu11 -- scale simp1y supported square reinforcedconcrete waff1e slab as wel1 as a fu11 - sca1e simp1y supported squarereinforced concrete sol id s1ab under short--term uniform1y di stributed1oads have been carri ed out. Tests resu1ts show the waff1e slab has near1ythe same fai 1ure mode1 as that of the solid s1ab, with the former behavedwel1 than the latter.2. The plast ic moment--adjusted ca1culate theory has been put forwardand practical1y tab1es have been made for the waff1e s1abs, which canalso be used for so1 id slabs. According to the empirica1 design methQds, wecan safe1y say that the method proposed can satisfy the 1imit state ofload bearing capacity as we11 as that of the serviceabi1ity l imit state.3. A waff1e slab was rep1aced by a f1at slab which had the same heightand the same geometrical parameters of the waff1e s1ab. The ult imate 1oadof the waff1e s1ab can be calcu1ated as easy as that of two -- way so1ids1ab. The deformation of the waffle slab can be calcu1ated by using thetab1es of two -- way so1id s1ab .but with a changing flexural rigiditycoefficient, which was very c1ose to the test va1ue in the uncracked andcracked stages.4. As for the design of this kind of structure mentioned above, thethesis' ana1yzed 'systematica1ly the inf1uence of the over1ay of thetwO--Way reinforcement on its u1timate. 1oad capacity, the deciding ofsuch important factors as the depth--span ratio and the rib spacing etc.