Research On Mechanical Properties Of Ceramsite Concrete Ultra-long Partition Walls

There are full of opportunities and challenges in the development of China's construction industry,it is an inevitable trend for China's construction industrialization to implement assembly building.Prefabricated partition slabs have been widely used as important building components in assembled buildings,but the cracking problems of slabs joints and the decreasing of construction efficiency caused by excessive construction joints are still troubles in the practical project.In view of the above problems,Ceramsite Concrete Ultra-long Partition Walls have been developed in this paper.As a new type of industrial product,the partition wall needs to be studied comprehensively before it can be used in practical projects.The properties of the new wallboards are studied from five aspects:characteristic of material,flexural behavior,impact resistance,anti-hanging property and compression performance,besides,bending and impact process of wallboard is simulated by finite element method.Finally,the requirements and suggestions for the construction measures of the wall are put forward.The specific contents are as follows:(1)Experimental study on the characteristic of the new wallboards' material.Through the experiment on the strength of ceramsite concrete during compressive age,it was found that the compressive strength of the material increases with logarithmically with age,and its early compressive strength is high.The constitutive relationship of the material was obtained by the experiment on the constitutive relation of ceramsite concrete under uniaxial compression,and it was found that the strain of the specimen increased linearly with the stress at the initial stage of loading,and the stress-strain relationship gradually deviated linearly with the increase of the load.When the stress exceeds 0.9fc,the test piece shows obvious cracks,and the strain starts to accelerate with the stress.Through the thermal insulation performance test of ceramsite concrete,it was found that the thermal conductivity of the material is only 27%of the ordinary concrete material,indicating that it has good thermal insulation performance;(2)Experimental study on flexural behavior,impact resistance,anti-hanging property and compression performance of the new wallboard.Through experimental study,it was found that the above four mechanical properties of the wall meet or exceed the requirements of the General Technical Requirements for Lightweight Strips for Building Partitions.In addition,the maximum tensile strain and maximum deflection of the wallboard both appear at the edge of the wallboard,and its bending failure mode has typical brittle characteristics.The failure modes of wallboard under compression are mostly fractured failure of weak walls of holes,besides,the compressive strength of the wallboard increases as the minimum rib-hole ratio increases.(3)Theoretical analysis of the flexural behavior,impact resistance,anti-hanging property and compression performance of new wallboard was carried out.After analysis,the theoretical calculation formulas for the flexural bearing capacity are proposed,and the theoretical formula of the stiffness of the wallboard is revised on the basis of the code,also a reasonable deflection formula is given.In addition,this paper also carries out theoretical analysis on the impact and anti-hanging resistance of wallboard,and the impact force of sand bags is tested,based on the theoretical analysis and test results,a reasonable formula for calculating the maximum impact force of sand bags is given,Meanwhile,the calculation methods for the impact bearing capacity and the hanging bearing capacity of wallboard are proposed.(4)Using ABAQUS finite element software to establish the flexural and impact model of the new wallboard,it is found that the stress distribution,deformation law,failure mode,ultimate bearing capacity of the model are consistent with the results of test and theoretical analysis by comparing the simulation results with the previous conclusions.(5)Several requirements are put forward for the storage,pre-construction preparation and installation methods of the Ceramsite Concrete Ultra-long Partition Walls,and several connections between wallboards and beams,columns,doors or windows are recommended.Through various research works,it is found that Ceramsite Concrete Ultra-long Partition Walls have the advantages of light weight,high early strength and excellent thermal insulation performance,but also its flexural,impact,anti-hanging and compressive performance exceed the requirements of the current specifications.Construction joints can be minimized to the greatest extent,the possibility of cracking at the joint and the construction cost can be reduced,and the construction efficiency and quality can be improved at the same time.This paper provides theoretical support for the design and construction of the new wallboard.