| Loading test is a dependable method to determine the loading-carrying capacity and deformation properties of foundation soil. The deep loading test is an experiment to test the strength and the deformation properties of certain layer in semi-infinite body. Compared with other soil test method and in–situ soil measurement, loading test can determine more reliable carrying layers, and the load-carrying capacity and elastic modulus is more reliable. For high-rise buildings, the physical and mechanical properties is not accurate enough because of the deep foundation and load-carrying layers. 《Code for Geotechnical Investigation of High-rise Buildings》and 《Code for Building Foundation Design》demand that loading test must be carried out to determine the bearing stratum, and the deformation modulus and load-carrying capacity of main bearing layers. At present, two deep-loading test methods commonly used in China and other countries are deep plate loading test and auger plate loading test. As early as 50's, our country started deep loading test, it is accept and press the plant and pass and spread the dint pillar descend go into the bore bottom. The jack pass to spread the dint pillar to accept to press the plank to bring pressure, from the form of the jack press the manifestation to accept to press the knothole lotus to carry, the bore bottom accept to press the knothole to move in the earth's surface measure to spread the dint pillar of under sink what quantity get. This kind of carries the lotus to experiment the method to exist two key problems: Superficial while is the natural rock soil that the neat bore bottom and assurances accept to press the plank to fall directly after pare away, namely the clearance bore bottom remnant and the bore wall stability problem; Two is a formula calculation that carries the lotus with the shallow layer to experiment to transform the amount of mold, because of the shallow layer and deep carry the lotus to experiment to press the plank the foundation soil of is different in response to the dint appearance, so think that the calculation result is out of accordance with physically; Also was little at that time because of the high building, to deep carry the lotus the on trial request is as well little, so deep carried the lotus to experiment the application at that time less. Since 1990's, with the increase of high-rise building, deep-loading test wasa northeast of request.92 year of the to deep carried the lotus to experiment to also have the surveys to design the institute for research to research to manufacture the deep flat panel to carry the lotus to experiment the instrument( type JZ-1).94Since year that set of on trial instrument carries on measuring actually in local several key figures the building place, providing the precious and deep rock soil body to calm down to carry the lotus to experiment the data for the high building design. .Moreover, know according to the article that Xinjiang synthesizes to investigate to design the institute for research to announce, that hospital as early as 92 years, June has already investigated deep flat panel carries the large unit supply and marketing mansion that the lotus experiments to used for Urumqi City etc. many projects with architectural key figures in the engineering, applying the result better. The deep flat panel carries the development application that the lotus experiment in the our country, is with our country the key figures construct the development of demand is related, the engineering practice to express that this kind of calms down to carry the lotus to experiment to also have the adaptability and credibilities under the condition of deep bore. But, also reflect for extend its application and raise some problem that it tests the accuracy demand to solve: (1)The on trial device adds to carry to spread the dint system ands to move to test the system to affect the problem to the test accuracy and the test depth. (2)The Existing two the basic data the that carry the lotus the to experiment the to get: The is accepting the to the press the lotus the on the plank to the carry( P) the and the correspond the lotus the to the carry under the of the sink the and decline value( S), the is the not the from accept the to the press the plank the to measure the directly of, the but has been spread the dint pillar to spread to the earth's surface to test to find out of, because of spreading the flection of the dint pillar to transform and it with an output Rub the resistance of the bore wall, make in the P, the S value that the earth's surface test to find out and accept to press the actual P, the S value of plank to appear the error margin, that error margin impossible and accurate estimate, and bore deeply and more deep, error margin more big, affect this kind of test accuracy that experiments the method and test the depth. Currently the local and deep flat panel carries the data manifestation that lotus experiment, it tests the bore deeply and generally within the scope of 20 m. The bore bottom handles and measures the perpendicular problem ofbore The bore bottom processing, expel the remnant, the bore wall stability and drill a hole to protect to keep the etc., the technique problem can not resolve effectively, so accept to press the plank and can't insure to fall in the bore bottom, the true and dependable that test is as a result is not high. The deep flat panel carries the lotus to experiment to transform how the amount of mold compute the problem. The, the can know: the deep foundation design, compound the foundation designs etc. the rock soil engineering the design need from deep carry the lotus to experiment the engineering characteristic parameter of provide the deep foundation soil, but existing and deep carry the lotus to experiment the method and techniques to equip and exist to have the as state above problem, therefore, further perfect and deep carry the technique device and the kit techniques that lotus experiment, with satisfy engineering design to the request that engineering investigate, become very the research topic of the meaning. 1)Aim at the existent problem of above-mentioned equipments, my hospital researches to manufacture a deep flat panel to carry the lotus to experiment the device by myself. That studies the result is a set of to measure at home and abroad currently deeply most deeply, test the test that accuracy is free from the deep flat panel of measure the deep influence to carry the lotus to experiment equip and should equip operation the rules distance and deep bore become the bore protects to keep and protect the craft technique of the wall stability. 2)A deep flat panel carries the lotus to experiment to equip from accept to press the plank, pressure to spread the feeling machine and spread the dint tube pillar, to move the pole and it pulls to keep the device, hydraulic-pneumatic jack, oil pump, to move to spread the feeling machine, automatic examination control instrument, anti-dint beam and ground anchor man etc.s to constitute. 3) An on trial instrument contain following characteristics: The Accept the to the press the knothole the to the move the diagraph, the through the an the appropriative steel the move the pole, the it's the bottom the carries the ballthe the in close the to the accept the to press the knothole the inside, the top the end connects the with each the other with the a thin the steel wire rope, the that rope the another a the carry through the direction pulley hang the heavy thing, the weight of the heavy thing is equal to or is no smaller than to move the pole heavy of 3/4, with the assurance move the pole to be placed in to pull to keep the appearance, andwith accept to press the synchronous ambulation of plank, from the that moves the pole top end move spreads the feeling machine spread of move the quantity would be accept to press the actual of knothole move. This kind of diagraph accuracy that moves to measure the system is free from the deep influence of bore. (3)The pressure spread the feeling machine pack at spread the dint pillar lower part and accept to press the plank upper part of conjunction, the pressure spreads the pressure value that the feeling machine spread to would be to accept to press the pressure value that the plank accepts physically. The Spreading thus resistance of Rub the resistance between the dint pillar and the bore wall will not affect to accept to press the plank the to spread the actual the measured value the of the feeling machine up, the depth of the test bore does not affect the lotus to carry the diagraph accuracy. (4)The adoption have another passage deep the Foundation examines the instrument automatically, the automatic manifestation, the short time saves to print the data of P-S-T the in good the time also; The automatic the control oil the pump adds the to press, carrying in the all levels lotus is steady to press the function under the auto that keep the high accuracy. The deep flat panel carries the bore processing technique that the lotus experiments to test the bore, the is a decisive technique of the reliability and influence that method application foreground that relates to to this kind of to carry the lotus to experiment the method to measure the result actually. The processing technique inside the bore include: The bore bottom is neat and expels the remnant; The bore wall stabilizes and protects to keep the problem of wait several. My hospital puts forward the homologous technique measure to above-mentioned problem of, and applies in the fulfillment, obtaining to compare good of result. Transform the calculation of the amount of mold According to the construction department synthesize to investigate to the design the institute for the research to the attend to the treasure and the and the together the university the ZHU the XIAO3 LIN2 the wait the for the someone of the research think, the deep flat panel carry the lotus to experiment and can make use of the type calculation soil transform the amount of mold: E0==I0I1(1-u2)Pd/S Where E0 is the mold of transform, kPa; I0 is the rigid accept to press theplank shape to the influence coefficient that sink to decline, the circular accepts to press the plank I0= p/4=0.785; I1 is the accept to press the correction coefficient that the plank covers up the deep Z hour, the when Z> d, I1?0.5+0.23d/2 ; when deep pit experiment I1=1; The poise of the u-soil is loose to compare, the crushed stones soil take 0.27, the sandy soil, the glue the soil the to take 0.3, the powder quality the glues the soil to take 0.35, the glue th soil the to take 0.42, don't drain under condition the saturation glues the soil to take 0.5; D-accept to press the plank diameter, mm; P-with loading the dint characteristic be worth to should of lotus carry, kPa; S-with loading the dint characteristic be worth to should of move, mm. The hospital made use of a deep flat panel to carry the lotus to experiment the instrument to do two on trial works that try the bore in the long spring engineering college east school District hospital practice base. Test the bore 1 and the test bore 2 of curve of P-S see the figure 2, Figure 2 1 number and 2 numbers experiment to order the deep flat panel to carry the lotus to experiment the curve diagram... |
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