Application Research Of Limestone Manufactured Sand Concrete In Guangxi Area

At present,Infrastructure construction is developing rapidly in Guangxi,the demand for natural sand is increasing,while the qualified sand source of natural sand is decreasing continuously,which makes the contradiction of engineering construction in Guangxi area more and more obvious,it also increases the cost of the project.limestone is widely distributed in Guangxi area,such as Mashan county and Longan county.Therefore,natural sand is replaced by limestone manufactured sand as the fine aggregate of concrete,which is significant to the project cost and environment protection.In this paper,physical properties of the Mashan limestone manufactured sand and mechanical properties of the five kinds of concrete with different contents of stone powder are studied by experiment.The ultimate bearing capacity of the natural sand concrete beam and the manufactured sand concrete beam with stone powder content of 3%and 12%with the same size,reinforcement and mix ratio was analysed by ANSYS finite element software.The static load tests were carried out,and the mechanical properties of concrete beams were analysed.Experiment results are shown as below:1)The physical properties of Mashan limestone manufactured sand can meet the requirements of ordinary concrete.The preparation method of ordinary concrete is also suitable for the manufactured sand concrete.,the strength of concrete has a good performance when the sand concrete water cement ratio is about 0.45.2)The mechanical properties of the Mashan limestone manufactured sand concrete have the best performance when the content of limestone powder is about 3%,and it's better than natural sand concrete.3)Suggestions on the conversion coefficient of axial compressive strength of limestone concrete in Guangxi area was put forward,The relationship between the compressive strength and the concrete elastic modulus was fitted,which provides reference for the application of the limestone manufactured sand concrete in engineering of Guangxi area.4)The ultimate bearing capacity of the natural sand concrete beam is above the ultimate bearing capacity of manufactured sand concrete beam of 3%content of stone powder,and it's below the ultimate bearing capacity of manufactured sand concrete beam of 12%content of stone powder.The ultimate bearing capacity,crack width,cracking load and deflection of concrete beams have a higher guarantee rate based on the standard,which provides a reference for the application limestone manufactured sand concrete in practical projects in Guangxi area.