【正文】 , present the stress of pressing in the middle. (2)Restrain the stress: All of the structure ones or it restrain external one some border,can39。 (2)Prevent the foundation from rising and falling too big。 Secondly, backfill varia and ponding should clear up the pit bottom in the front , respond to densification with layers when backfill. Waterproof structure vicinity layer pounds true backfill , self is a reliable and economical as well water proofing drapery under the ground. In project basement engineering construction Shanghai,since organizing water proofing down to earth strictly with all above seven passes, the concrete is under construction , effect is paratively percolating water phenomenon does not appear.Conclusions Construction temperature and relation of crack in concrete the above carry on preliminary discussion of theory and practice, though the academia has different theories to origin cause of formation and puting technology of the concrete crack, but to concrete prevention and improving the measure suggestion to relatively unify , application in practice result fine too at the same time, concrete to is it observe , pare more more by us to want in constructing, analyse more , summarize more after going wrong , bine many kinds of prevention and deal with the measure, the crack of the concrete can be avoided. 淺談混凝土的施工過程中溫度與裂縫控制By G. K. Kululanga, W. Kuotcha, R. McCaffer, Member, ASCE, and F. EdumFotwe美國土木工程師學(xué)會摘 要 為了防止業(yè)主對混凝土工程的索賠,就必須做好施工過程中溫度與裂縫控制。首先，在施工中混凝土常常出現(xiàn)溫度裂縫，影響到結(jié)構(gòu)的整體性和耐久性。在大體積混凝土中，溫度應(yīng)力及溫度控制具有重要意義。The waterproof structure reinforced bar is concentrated Should concrete altitude when higher , respond to according to the material stipulating that you go down material opening the door on form board or using string of barrels (chute) to fall, prevent a cement paste from parting from aggregate for , avoid at the same time also the cement paste or the concrete accumulating the place and cement paste alternating in the reinforced bar loosely splashing sticky Yu form board with outsideNow that material is difficult under bringing about a later, the surface affecting structure glossy , bees in the future leakage hidden trouble.4) concretes vibrating beat one important ring being to ensure that the concrete is closely knit , defend against to seep with a stick. Also, should adopt fixed point vibrating , handle meticulously on basis expecting that under determining the amounts of the ponents of a substance homogeneously in fixed point .Pay attention to high and low tier of linking upNow that needing to prevent from miss and vibrating , not vibrating enough , being going to prevent a fault from vibrating again, Need to forbid using prying the method ing to aid to vibrate moving a reinforced bar or shaking a reinforced bar especially, such separates to making the front already concrete the reinforced bar and concrete shaking the reality part , causes serious consequences. 5) being ready for the assured source of life degree taking over thick fluid measure , adjusting in time to collapse seriously .Average waterproof concrete structure construction, the construction joint being under construction respectively , posing namely on erecting wall sells be bottom board and vertical wall at reduced irrigate thick a layer of 5 cm ~ 10 cms surname indicia cement mortars in seam place first linking up closely knitting tier, in order to ensuring that the seam place vibrates when concrete vertical , improve step by step with concrete an altitude39。 (6)The concrete with medium and longterm and exposed construction builds a piece of surface or thin wall structure, take the measure of keeping warm in cold season。t deformation doing, often cause the crack too. The concrete is a kind of fragility material , tensile strength is about 1/10 of the pression strength, is it carry on one39。t out of shape and stress not cause not free. Such as case roof beam roof concrete and guardrail concrete. This two kinds of temperature stresses draw back stresses caused to act on with the doing of concrete together frequently. It is a more plicated job to want to analyse the distribution , size of the temperature stress accurately according to known temperature. In case of great majority , need to rely on the model test or the number value to calculate. To is it make temperature stress have sizable limp to creep concrete, at the stress accounting temperature, must consider the influence that creep , calculate concretly that no longer states thinly here. Control and preventing the measure of the crack of 3 temperature For prevent crack , lighten temperature stress can from control temperature and is it is it set about to restrain terms from two to improve. The measure of controlling temperature is as follows: (1)Is it improve aggregate grade mix , is it do rigid concrete to spend , mix mixture to adopt, is it guide angry pharmaceutical or plastification pharmaceutical ,etc. measure in order to reduce cement consumption of concrete to add。 (3)Rational arrangement construction process, prevent the too big discrepancy in elevation and side from exposing for a long time。本文通過多年的現(xiàn)場觀察，通過查閱有關(guān)混凝土內(nèi)部應(yīng)力方面的專著，對混凝土溫度裂縫產(chǎn)生的原因、現(xiàn)場混凝土溫度的控制和預(yù)防裂縫的措施進行等進行闡述。其次，在運轉(zhuǎn)過程中，溫度變化對結(jié)構(gòu)的應(yīng)力狀態(tài)具有顯著的不容忽視的影響。究其原因，我們對混凝土溫度應(yīng)力的變化注意不夠是其中之一。s had guarded against reinforced bar protective layer deviation piece big mass mon failings.The concrete stirring and mixing makes and transportsSince the waterproof concrete requires that higher closely knit , reason why stir and mix system also need to have the fairly good homogeneity , should be ready for burning as follows almost for this purpose 1) ensures that mixing time , mixing at every time are secondary jump into a expect the general ejection of pact block of wood less than 2 mins. 2) should use the apposition agent , the solution queen who should manufacture certain thickness from apposition agent adds the mixer inner, the dried powder