Self-compacting Lightweight Aggregate Concrete Column Axial Compression Bearing Capacity Study

With the rapid development of science and technology and the improvement of people's quality of life,people are also beginning to pursue the pursuit of new building materials.In this paper,the existing ordinary concrete has a large self-weight,and requires mechanical vibration to fill the concrete when pouring.A series of problems such as pollution and poor seismic performance,using fly ash lightweight ceramsite,ordinary fine sand,admixture,ordinary Portland cement as the main material,designed the mix ratio of self-compacting lightweight aggregate,and Self-compacting lightweight aggregate concrete replaces ordinary concrete as the base material of the column,and designs and produces a self-compacting lightweight aggregate concrete column with light weight,strength conforming to the specification requirements,convenient construction,vibration-free pouring during pouring,and good mechanical properties.This article mainly carried out the following work:(1)Refer to the"Technical Regulations for Self-Compacting Concrete Application"(JGJT283-2012)and"Technical Regulations for Lightweight Aggregate Concrete"(JGJ51-2002),taking into account the effects of lightweight aggregates and mineral admixtures,and self-compacting in combination with tests.For the adjustment of the mix ratio of lightweight aggregate concrete,the strength grades were SCLC30,SCLC35,SCLC40 and SCLC45,and the apparent density was1630kg/m~3,1734kg/m~3,1820kg/m~3 and 1864kg/m~3.The concrete was then filled with the self-compacting concrete designed in this paper instead of ordinary concrete as the base material of the column.The self-compacting lightweight aggregate concrete column members were designed and fabricated.(2)The axial stress test of the self-compacting lightweight aggregate concrete column was carried out,and the different concrete strength grades(SCLC30,SCLC35,SCLC40 and SCLC45)and different longitudinal reinforcement ratios were studied(1.3%,1.7%,2.3%and 3%)and different slenderness ratios(4,4.75,5.5 and 6.25)have an effect on the compression characteristics of the positive section axial center;the results show that the self-compacting lightweight aggregate concrete column members have good compressive properties.It undergoes elastic phase,elastoplastic phase and failure phase when subjected to axial load to component failure,and the damage is manifested as brittleness;different concrete strength grades,longitudinal reinforcement ratio and slenderness ratio are all on the axis of the component.The compressive strength of the heart has a significant effect.For example,its compressive bearing capacity and compressive stiffness increase with the increase of the longitudinal compressive steel reinforcement ratio and concrete strength,and decrease with the increase of the slenderness ratio;its cracking load With the increase of concrete strength and slenderness ratio,the effect of longitudinal steel reinforcement ratio on the cracking load and tensile properties of axial compression members is not obvious.(3)Combining the test,the theoretical calculation of the calculation formula of the axial compression bearing capacity of the self-compacting lightweight aggregate concrete column is carried out,and the axial compression bearing capacity of the self-compacting lightweight aggregate concrete column suitable for the design of the paper is obtained.Calculation formula.(4)Based on the experiment,the numerical model was established by using the finite element software ABAQUS,and the numerical simulation analysis of the test conditions was carried out.The analysis results were compared with the test results,and the results of the finite element analysis were in good agreement with the test results.degree.