低应变反射波法桩底反射信号问题的探讨的中期报告-第一文库 | 海量文档资源下载与分享平台

在线预览结束，喜欢就下载吧，查找使用更方便

5 金币

下载此文档

/ 2

下载提示文本预览

如果您无法下载资料，请参考说明：

1、部分资料下载需要金币，请确保您的账户上有足够的金币

2、已购买过的文档，再次下载不重复扣费

3、资料包下载后请先用软件解压，在使用对应软件打开

低应变反射波法桩底反射信号问题的探讨的中期报告Abstract:Thelow-strainreflectionwavemethodiscommonlyusedinpilefoundationqualitytesting.However,thebottomreflectionsignalofthepileoftenhasacomplicatedwaveformanditisdifficulttodistinguishthetruereflectionsignalfromthesecondaryreflectionsignals.Inthisreport,weanalyzedthecausesofthecomplexwaveformofthebottomreflectionsignalandproposedseveralmethodstoimprovethesignalquality.Introduction:Thelow-strainreflectionwavemethodisoneofthemostcommonlyusedmethodsforpilefoundationqualitytesting.Itisanon-destructivetestingmethodthatusesasmallhammertogeneratealow-energyimpactonthepilehead,andthereflectedwavesignaliscapturedbyareceiver.Thetime-domainwaveformofthereflectedwavesignalcanbeusedtoanalyzethepileintegrityanddetectanydefects.However,thebottomreflectionsignalofthepileoftenhasacomplexwaveform,whichmakesitdifficulttodistinguishthetruereflectionsignalfromothersecondarysignals.Inthisreport,weanalyzedthecausesofthecomplexwaveformofthebottomreflectionsignalandproposedseveralmethodstoimprovethesignalquality.Analysis:Thecomplexwaveformofthebottomreflectionsignalismainlycausedbythefollowingreasons:1.Reflectionatthepiletip:Ifthepiletipisnotproperlyseatedorthereissignificantsoilresistanceatthetip,thereflectedwavesignalwillcontainasignificantportionofthereflectionfromthepiletip.Thissignalwillbehighlyattenuatedanddistorted,makingitdifficulttodistinguishfromotherreflectionsignals.2.Multiplereflectionatthesoil-pileinterface:Whenthereflectedwavesignalencountersachangeinsoilproperties,suchasalayerofdifferentsoiloravoid,itwillproducemultiplereflections.Thesereflectionswillinterferewitheachotherandcreateacomplexwaveform.3.Reflectionfromthesurroundingstructure:Ifthepileisclosetoarigidstructureorotherpiles,thereflectedwavesignalwillalsocontainreflectionsfromthesenearbystructures.Thesereflectionswilladdtothecomplexityofthewaveform.Toimprovethesignalquality,weproposethefollowingmethods:1.Properseatingofthepiletip:Thepiletipshouldbeproperlyseatedtominimizethereflect