国开在线答案
- 2022-09-12 [简答] 5．采取土样时，造成土样扰动的原因有哪些？要点：（1）外界条件引起的土试样的扰动，如钻进工艺、钻具、钻压、钻速、取土方法的选择等，若在选用上不够合理，都能造成其土质的天然结构被破坏。（2）采样过程造成的土体中应力条件发生了变化，引起土样内的质点间的相对位置的位移和组织结构的变化，甚至出现质点间的原有载聚力的破坏。（3）采取土试样时，不论采用何种取土器，它都有一定的壁厚、长度和面积，当切入土层时，会使土试样产生一定的压缩变形。
- 2022-09-12 [单选] 阐述原位测试的优缺点及其与室内土工的关系。要点：原位测试与室内土工试验相比，主要具有以下优点： （1）可以测定难以取得不扰动土样(如饱和砂土、粉土、流塑淤泥及淤泥质土、贝壳层等)的有关工程力学性质; （2）可以避免取样过程中应力释放的影响; （3）原位测试的土体影响范围远比室内试验大，因此代表性也强: （4）可大大缩短地基土层勘察周期。但是，原位测试也有不足之处。例如：各种原位测试都有其适用条件，若使用不当则会影响其效果；有些原位测试所得参数与土的工程力学性质间的关系往往建立在统计经验关系上；影响原位测试成果的因素较为复杂，使得对测定值的准确判定造成一定的困难；还有，原位测试中的主应力方向往往与实际岩土工程中的主应力方向并不一致等。因此，土的室内土工试验与原位测试，两者各有其独到之处，在全面研究土的各项性状中，两者不能偏废，而相辅相成。
- 2022-09-12 [单选] —Hello,mayIspeaktoHenry?—_______
- 2022-09-12 [单选] —Ifyou're short-listedfortheinterview,we'llringyoubyFriday.—_______
- 2022-09-12 [单选] Thereare ______studentsinClassOnethaninClassTwo.
- 2022-09-12 [单选] Whatmattersishowyourhouselooksandhowit_____ youandothersresidingin it.
- 2022-09-12 [单选] Thisgardenisthreetimesas______asthatone.
- 2022-09-12 [简答] Top3GreenHomeInnovations .Therearemanythingsyoucandotoreducecarbonemissionandhelptomaketheearthabetterplaceforfuturegenerations.Hereareafewsuggestions. AlthoughLEDlampscostmoremoneythanstandardincandescentorcompactfluorescentbulbsdoatthebeginning,theselong-lastingLEDlampswilleventuallybeworththemoneybecauseofnergy saved.LEDlampsalsoproduceacleaner,morenaturallight. .“Water”isahottopic,especiallyintheSouthwest.Household waterfiltersarenowavailabletocleanandreusewaterfromshowersandbaths.Graywaterreusesystemsredirecttheusedwaterfromwashingmachinestolawnsorgardens. .Buildingmaterialsandembellishmentslikepaintandcarpetscan emit chemicalcompoundsintotheatmosphere,andbecauseahomeisanenclosedspace,thosecompoundscansometimesaccumulatetodangerouslevels.Installingawhole-houseairpurificationsystemisonewaytokeepindooraircleanandcirculating. Going“green”doesn'thavetobeachallenge.Ahomeisalong-terminvestment.Youdon'thavetostartoverfromcratch. Makesmallchanges.ChooseenvironmentallyfriendlypaintorLEDbulbs. Chancesarethatyourhomewillneedimprovementseventually.Wheneverpossible,chooseupgradesthatwillreduceyourcarbonfootprint.It'sgoodfortheplanet,andit'sgoodforyou.A.Inrecentyearsindoorairpollutionhasgotalotofattention.B.AirPurificationC.WaterRecyclingD.Inthelastdecadeagrowingnumberofpeoplewereinterestedinconservingenergyandpreservingtheenvironmentbyliving“green”E.LEDLighting
- 2022-09-12 [单选] 经验事实表明， 的滥用是社会动荡的根源。
- 2022-09-12 [单选] 是自由主义的核心原则。