Stiffening-ribbed-hollow-pipe cast-in place reinforced concrete girderless floor is a new-style hollow girderless floor system. Model experimental researches of simply-supported floor and four-corners bearing floor ha...Stiffening-ribbed-hollow-pipe cast-in place reinforced concrete girderless floor is a new-style hollow girderless floor system. Model experimental researches of simply-supported floor and four-corners bearing floor have been done on this new kind of floor system in this paper. The experiment results show that the floor system has good mechanical property such as high bearing capacity, big rigidity and good tensility. A theoretical method is presented in this paper that the stiffening-ribbed-hollow-pipe girderless floor can be analyzed by being converted equivalently to orthotropic solid slab. It is indicated that the method is correct and reasonable according to the contrast between theoretical calculated results and experimental measured results. The theoretical results coincide with the measured results well.展开更多
Upon the view of this work, industrial floor is a vital structure due to its relation to quality of production, labor comfort, and human health. Flooring costs may reach 20% of single-story building construction expen...Upon the view of this work, industrial floor is a vital structure due to its relation to quality of production, labor comfort, and human health. Flooring costs may reach 20% of single-story building construction expenditure, and the consumption of concrete for floors may come to 40% - 50% of the total size of concrete. Thereby, the efficient design of floor will reduce materials consumption and labor, and will increase the endurance of the floor. Fiber reinforcement reduces the thickness of the subfloor about 20% - 30%, hence enabling to reduce the consumption of cement and fillers. The use of fiber meshes will enable to save 30% - 40% of steel. Despite the flexible use of fiber in concrete reinforcement saves effort and money, still fiber reinforced concrete is lacking additional regulations in Jordan.展开更多
Floor diaphragms may provide an effective solution for reducing the seismic vulnerability of masonry buildings. Unfortunately, diaphragms are usually not present in historical building with wooden floors but often the...Floor diaphragms may provide an effective solution for reducing the seismic vulnerability of masonry buildings. Unfortunately, diaphragms are usually not present in historical building with wooden floors but often they are non present even in old R/C buildings where floors were made without shear reinforcement. A possible strengthening technique could be based on the application of a thin concrete plate reintbrced with a welded mesh. In order to reduce the thickness of the plate, some suitable solutions may be obtained by using Fiber Reinforced Concrete (FRC) since the minimum concrete cover is no longer required because the reinforcement (fibers) is spread all over the concrete matrix. The adoption of FRC floor diaphragms is proposed and discussed in this paper; the early results from a preliminary numerical study are analyzed in order to asses the feasibility of this new strengthening technique and better organize an experimental program that is currently in progress.展开更多
This paper experimentally investigates the namely, normal density concrete and structural low-density energy absorption potential of two types of concrete floors, concrete, containing secondary (shrinkage and tempera...This paper experimentally investigates the namely, normal density concrete and structural low-density energy absorption potential of two types of concrete floors, concrete, containing secondary (shrinkage and temperature) reinforcements. The test program considered the following secondary reinforcements: 1) traditional welded-wire steel mesh, 2) steel fiber and 3) poly composite fiber. To estimate the extent to which crushing of floor slab materials would help absorb energy, a series of concrete penetration tests employing patch loading was undertaken on scaled down model slabs. Each concrete-secondary reinforcement combination considered slabs of 50 mm in depth with square plan dimensions ranging from 50 to 500 mm, resulting in a total of 30 test specimens. The first part of the paper discusses the test specimens, the test setup, and the test procedure. The second part of the paper presents the experimental results and establishes the energy absorption of different concrete- secondary reinforcement combinations. Sieve analysis results of the crushed specimens were used to derive a "work index" value that relates the pulverized particle size distributions to energy inputs. The work index values of concrete-secondary reinforcement systems can be used to assess the energy dissipation potential associated with such floor slabs in buildings undergoing progressive collapse. The results indicate that floors with secondary reinforcements could play an important role in helping arrest global progressive collapse.展开更多
文摘Stiffening-ribbed-hollow-pipe cast-in place reinforced concrete girderless floor is a new-style hollow girderless floor system. Model experimental researches of simply-supported floor and four-corners bearing floor have been done on this new kind of floor system in this paper. The experiment results show that the floor system has good mechanical property such as high bearing capacity, big rigidity and good tensility. A theoretical method is presented in this paper that the stiffening-ribbed-hollow-pipe girderless floor can be analyzed by being converted equivalently to orthotropic solid slab. It is indicated that the method is correct and reasonable according to the contrast between theoretical calculated results and experimental measured results. The theoretical results coincide with the measured results well.
文摘Upon the view of this work, industrial floor is a vital structure due to its relation to quality of production, labor comfort, and human health. Flooring costs may reach 20% of single-story building construction expenditure, and the consumption of concrete for floors may come to 40% - 50% of the total size of concrete. Thereby, the efficient design of floor will reduce materials consumption and labor, and will increase the endurance of the floor. Fiber reinforcement reduces the thickness of the subfloor about 20% - 30%, hence enabling to reduce the consumption of cement and fillers. The use of fiber meshes will enable to save 30% - 40% of steel. Despite the flexible use of fiber in concrete reinforcement saves effort and money, still fiber reinforced concrete is lacking additional regulations in Jordan.
文摘Floor diaphragms may provide an effective solution for reducing the seismic vulnerability of masonry buildings. Unfortunately, diaphragms are usually not present in historical building with wooden floors but often they are non present even in old R/C buildings where floors were made without shear reinforcement. A possible strengthening technique could be based on the application of a thin concrete plate reintbrced with a welded mesh. In order to reduce the thickness of the plate, some suitable solutions may be obtained by using Fiber Reinforced Concrete (FRC) since the minimum concrete cover is no longer required because the reinforcement (fibers) is spread all over the concrete matrix. The adoption of FRC floor diaphragms is proposed and discussed in this paper; the early results from a preliminary numerical study are analyzed in order to asses the feasibility of this new strengthening technique and better organize an experimental program that is currently in progress.
文摘This paper experimentally investigates the namely, normal density concrete and structural low-density energy absorption potential of two types of concrete floors, concrete, containing secondary (shrinkage and temperature) reinforcements. The test program considered the following secondary reinforcements: 1) traditional welded-wire steel mesh, 2) steel fiber and 3) poly composite fiber. To estimate the extent to which crushing of floor slab materials would help absorb energy, a series of concrete penetration tests employing patch loading was undertaken on scaled down model slabs. Each concrete-secondary reinforcement combination considered slabs of 50 mm in depth with square plan dimensions ranging from 50 to 500 mm, resulting in a total of 30 test specimens. The first part of the paper discusses the test specimens, the test setup, and the test procedure. The second part of the paper presents the experimental results and establishes the energy absorption of different concrete- secondary reinforcement combinations. Sieve analysis results of the crushed specimens were used to derive a "work index" value that relates the pulverized particle size distributions to energy inputs. The work index values of concrete-secondary reinforcement systems can be used to assess the energy dissipation potential associated with such floor slabs in buildings undergoing progressive collapse. The results indicate that floors with secondary reinforcements could play an important role in helping arrest global progressive collapse.