地基基础检测 技术 Theoretical knowledge of shallow plate load tests for foundation testing technology II-浅层 平板载荷试验理论知识65课件讲解

地基基础检测技术浅层平板载荷试验理论知识(二)

Theoreticalknowledgeofshallowplateloadtestsforfoundationtestingtechnology(II)设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation010101设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation1.反力装置

1.Reactiondevice压重平台反力装置

Reactiondeviceofballastplatform设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation提供的反力不得小于最大加载量的1.2倍

Thereactionprovidedshallnotbelessthan1.2timesofmaximumloadingcapacity应对其主要受力构件进行强度和变形验算

Checkingcalculationsshallbeperformedonstrengthanddeformationofitsmainload-bearingmember压重应在试验前一次加足

Theballastshallbefullyaddedatonetimebeforethetest施加于地基的压应力不宜大于地基承载力特征值的1.5倍

Thecompressivestressappliedtothefoundationshallnotbegreaterthan1.5timesthecharacteristicvalueofthebearingcapacityofthefoundation压重平台反力装置

Reactiondeviceofballastplatform压重平台反力装置应符合下列规定:

Thereactiondeviceofballastplatformshallmeetthefollowingrequirements:1.反力装置

1.Reactiondevice设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation为什么说加载反力装置能提供的反力不得小于最大加载量的1.2倍?

Whyisitthattheloadingreactiondeviceshallbecapableofprovidingareactionnotlessthan1.2timesofmaximumloadingcapacity?主要是考虑平台重心相对于千斤顶轴心的偏心影响可能造成的倾斜。

Thepossibleinclinationcausedbytheeccentricityoftheplatformcenterofgravityrelativetothejackaxisismainlyconsidered.1.反力装置

1.Reactiondevice岩基载荷试验

Rockfoundationloadtest为什么压重应在试验前一次加足?

Whyshouldtheballastbefullyaddedatonetimebeforethetest?加载反力装置应优先选用压重平台反力装置。与桩的静载试验相比，平板载荷试验的试验荷载要小得多，因此，要求压重应在试验前一次加足。

Thereactiondeviceofballastplatformshallbepreferredforloadingreactiondevice.Theplateloadtesthasamuchsmallertestloadthanthestaticloadtestofthepile.Therefore,itisrequiredthattheballastshouldbefullyaddedatonetimebeforethetest.1.反力装置

1.Reactiondevice岩基载荷试验

Rockfoundationloadtest为什么说压重平台支墩施加于地基的压应力不宜大于地基承载力特征值的1.5倍?

Whyshouldthecompressivestressappliedtothefoundationbythebuttressoftheballastplatformnotbegreaterthan1.5timesthecharacteristicvalueofthebearingcapacityofthefoundation?考虑压重平台施加于支墩地基的荷载不超过地基承载力极限值。因为试验措施为临时措施，所以没必要要求小于特征值，以减少试验准备的工作量。

Itisconsideredthattheloadappliedbytheballastplatformonthebuttressfoundationdoesnotexceedthelimitvalueofthebearingcapacityofthefoundation.Becausethetestmeasuresaretemporary,itisnotnecessarytorequirelessthanthecharacteristicvaluetoreducetheworkloadoftestpreparation.1.反力装置

1.Reactiondevice设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation2.荷重测量装置

2.Loadmeasuringdevice直接测定

Directlymeasuretheload形式一

TypeI测定油压，根据干斤顶率定曲线换算荷载

Measuretheoilpressureandtheloadshallbeconvertedaccordingtothejackratingcurve形式二

TypeII设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation3.位移量测装置

3.Displacementmeasuringdevice或

or位移传感器

Displacementsensor大量程百分表

Longrangedialgauge设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation3.位移量测装置

3.DisplacementmeasuringdeviceS>0.5m2安装数量

InstallationQuantity位移测

Displacementmeasuring量仪表

instrument位移测

Displacementmeasuring量仪表

instrumentS≤0.5m2位移传感器或大量程百分表安装应符合下列规定：

Theinstallationofdisplacementsensororlongrangedialindicatorshallmeetthefollowingrequirements:承压板

Bearingplate承压板

Bearingplate设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation3.位移量测装置

3.Displacementmeasuringdevice位移传感器或大量程百分表安装应符合下列规定：

Theinstallationofdisplacementsensororlongrangedialindicatorshallmeetthefollowingrequirements:承压板

Bearingplate承压板

Bearingplate位于承压板每边中点

Atthemidpointofeachsideofthebearingplate宜为25mm~50mm

Shallbe25mm~50mm设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation基准桩和基准梁应具有一定的刚度

Thereferencepileandreferencebeamshallhaveacertainstiffness3.位移量测装置

3.Displacementmeasuringdevice基准梁的一端应固定在基准桩上

Oneendofthereferencebeamshallbefixedtothereferencepile另一端应简支于基准桩上

Theotherendshallbesimplysupportedonthereferencepile设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation3.位移量测装置

3.Displacementmeasuringdevice固定和支撑位移测量仪表的夹具及基准梁应避免太阳照射、振动及其他外界因素的影响。

Fixtureforfixingandsupportingdisplacementmeasuringinstrumentandreferencebeamshallavoidtheinfluenceofsunlight,vibrationandotherexternalfactors.设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation4.仪器设备性能指标

4.PerformanceIndicatorsoftheInstrumentsandEquipment试验仪器设备性能指标应符合下列规定：

Theperformanceindicatorsofthetestinstrumentsandequipmentshallmeetthefollowingrequirements:压力传感器的测量误差不应大于1%，压力表精度应优于或等于0.4级；

Themeasurementerrorofthepressuresensorshallnotbegreaterthan1%,andtheaccuracyofthepressuregaugeshallbebetterthanorequaltograde0.4;试验用千斤顶、油泵、油管在最大试验荷载时的压力不应超过规定工作压力的80%。

Thepressureofjack,oilpumpandoilpipefortestundermaximumtestloadshallnotexceed80%ofthespecifiedworkingpressure.设备仪器及其安装

Equipmentandinstrumentsandtheirinstallation4.仪器设备性能指标

4.PerformanceIndicatorsoftheInstrumentsandEquipment试验仪器设备性能指标应符合下列规定：

Theperformanceindicatorsofthetestinstrumentsandequipmentshallmeetthefollowingrequirements:荷重传感器、千斤顶、压力表或压力传感器的量程不应大于最大加载量的3.0倍，且不应小于最大加载量的1.2倍；

Therangeofloadsensor,jack,pressuregaugeorpressuresensorshallnotbegreaterthan3.0timesofthemaximumloadingcapacityandshallnotbelessthan1.2timesofthemaximumloadingcapacity;位移测量仪表的测量误差不应大于0.1%FS，分辨力应优于或等于0.01mm。

Themeasurementerrorofdisplacementmeasuringinstrumentshallnotbegreaterthan0.1%offullscale,andtheresolutionshallbebetterthanorequalto0.01mm.设备仪器及其安装

Equipmentandinstrumentsandtheirinsta