natgillin/translations-raw huggingface dataset:
Ključne riječi: proboj, posmična naprezanja, temelji, propisi, eksperimenti, usporedna analiza 
Key words: punching, shear stresses, foundations, codes, experiments, comparative analysis
Foundations connect and coordinate the work of the structure with the subgrade, whose characteristics in relation to the structure are very different, particularly in terms of deformability. 
Temelji povezuju i usklađuju ponašanje konstrukcije građevine s podlogom, čije su karakteristike u odnosu na konstrukciju vrlo različite, naročito s aspekta deformabilnosti.
Although foundations have a significant impact on the behaviour of the structure and the surrounding soil, their calculation has not been sufficiently considered, neither in literature nor in technical regulations (standards, norms, requirements). 
Iako temelji bitno utječu na ponašanje konstrukcije i okolnog tla, njihovom se proračunu ne posvećuje dovoljna pažnja niti u stručnoj literaturi niti u tehničkim propisima (standardi, norme, zahtjevi).
Approximate calculations are most often used in the design of shallow foundations, particularly column footings, which are considered as rigid foundations, and a linear distribution of contact pressures is adopted. 
Pri projektiranju plitkih temelja, naročito temelja samaca, najčešće se primjenjuju približni proračuni gdje se temelji smatraju krutim i usvaja linearna raspodjela kontaktnih pritisaka.
In this calculation, a considerable significance is given to the punching shear control, i.e. to the control of column punching through the floor slab with or without shear reinforcement for the assumption of shear in the column area. 
U takvom proračunu važan dio predstavlja kontrola temelja na proboj (engl. punching) uslijed posmika, tj. provjera proboja stupa kroz ploču s armaturom ili bez armature za prihvat posmika u području stupa.
This control, as well as the punching control of floor slabs, are usually based on experimental research. 
Ona se, kao i kontrola proboja međukatnih ploča, najčešće zasniva na eksperimentalnim istraživanjima.
Due to a small number of experiments aimed at studying the puncture strength of foundation slabs, their analysis is often based on theoretical and/or empirical equations such as those applied to the problem of column punching through floor slabs, which is based on experimental research [1-6]. 
Zbog malog broja eksperimenata usmjerenih na istraživanje ponašanja temeljne ploče na proboj, često se za njihovu analizu koriste teorijske i/ ili empirijske odredbe kao kod problema proboja stupa kroz međukatnu ploču zasnovanog na eksperimentalnim radovima [1-6].
A broader historical review of solutions to column punching through the slabs without shear reinforcement is given in [7], but here the focus is mostly on punching through floor slabs. 
Širi povijesni pregled rješenja problema proboja ploča bez armature za prihvat posmika dan je u radu [7], ali je uglavnom opisan i objašnjen proboj stropova.
At that, it is noted that first recommendations of the American Concrete Institute (ACI) on flat plates, given in 1925, were based on experimental results presented byTablot [8], who investigated column footings, as cited in [7]. 
Pri tome je naglašeno da su prve preporuke Američkog instituta za beton (ACI) iz 1925. g. za ravne ploče, bile zasnovane na eksperimentalnim rezultatima Tablota [8], koji je istraživao temeljne ploče citirano prema [7].
However, the difference between the punching mechanism of foundation plates and floor slabs, which is due to their considerable difference in height ("slenderness"), has generally been neglected in technical regulations (hereinafter referred to as "regulations") [9]. 
Ipak, u tehničkim propisima (u daljnjem tekstu propisi) uglavnom je zanemarivana razlika mehanizma proboja ploča temelja i međukatnih ploča koja nastaje uslijed njihove znatne razlike u visinama ("vitkosti") [9].
This is due to the fact that experimental research relating to foundations has so far been quite scarce, primarily because of the complicated organization of such experiments, higher material costs, and a number of significant parameters that need to be taken into account. 
Razlog je tomu što su eksperimentalna istraživanja na temeljima do sada bila znatno rjeđa, prije svega zbog složene organizacije eksperimenta, većih materijalnih izdataka i brojnih utjecajnih parametara koje treba razmatrati.
Here, It should also be noted that investigations in real soil are rare and expensive, and so in many experiments real conditions are simulated by steel springs or BY a set of small hydraulic jacks connected in parallel [3]. 
Pri tome treba uzeti u obzir da su istraživanja na realnom tlu rijetka i skupa, pa je u više eksperimenata podloga simulirana čeličnim oprugama ili skupom malih hidrauličnih preša paralelno povezanih [3].
With regard to the punching control of foundations plates, technical regulations allow subtracting the load from the superstructure for a part of soil reaction, but differences between some regulations/standards are quite noticeable [9]. 
Tehnički propisi dopuštaju da se pri provjeri temeljnih ploča na proboj dio vrijednosti reakcije tla oduzme od opterećenja gornje konstrukcije, ali su primjetne razlike u pojedinim normama/propisima [9].
This is the why 17 column footings are studied in [9] (five actually resting on sand to enable analysis of the soil-structure interaction). 
To je razlog da je u [9] prikazano 17 ispitivanih temelja (pet realno oslonjenih na pijesak radi proučavanja interakcije konstrukcija-tlo).
The varied parameter was the shear span (b) (leg b marked in Figure 4) to effective depth (d) ratio, with values between 1.25 and 2.0, while the concrete strength was between 20 and 40 MPa. 
Varirani parametar je bio odnos raspona (kraka) posmika (b) (krak b obilježen na slici 4. i efektivne visine (d) s vrijednostima između 1.25 i 2.0, a čvrstoća betona je bila između 20 i 40 MPa.
According to [11], the most important parameters that should be included in the finite element method (FEM) are: geometry, material properties, and flexural reinforcement. 
Najvažniji su parametri koje treba obuhvatiti pri analizi metodom konačnih elemenata (MKE), prema [11], geometrija te karakteristike materijala i armature za prihvat savijanja.
The specificity of column footings is that they have a small b/d ratio. 
Prikazano je obuhvaćanje najvažnijih parametara mehanike loma za opis duktilnosti ili krtosti (engl. brittleness).
The punching test for two circular columns passing through the footing has been simulated numerically by means of the FEM [10]. 
Test proboja dvaju kružnih stupova kroz temelj simuliran je numerički MKE u [10].
It was established that failure mechanisms of slender slabs are significantly different from the mechanism related to footings. 
Pokazano je da se mehanizmi loma vitkih ploča bitno razlikuju od onoga kod temelja.
It is stated that the angle of shear cracks at foundation plates is between 50 - 60 0, which is significantly higher than the angle for slender slabs (30 - 40 0). 
Navodi se da je kut nagiba posmičnih pukotina temelja između 50 0 i 60 0 znatno veći nego kod vitkih ploča (30-40 0).
The b/d ratio for foundation plates is much smaller compared to the ratio applied for floor slabs (most regulations are based on them). 
Odnos b/d temelja je znatno manji nego kod međukatnih ploča (većina propisa se zasniva na njima).
It has been established by parametric analyses that the compressive strength of concrete has a greater impact on the punching bearing capacity of column footings, compared to "slender" plates that are typical to floor slabs. 
Parametarskim analizama je ustanovljeno da tlačna čvrstoća betona ima veći utjecaj na nosivost ploče temelja stupa na proboj nego što je to kod "vitkih" ploča karakterističnih za stropove.
It should be noted that the punching failure through a footing is brittle, and so the failure of one column/support can lead to the progressive and unexpected failure of neighbouring supports, as cracks and deformations remain small until just prior to the actual failure. 
Treba imati na umu da je lom probojem stupa kroz ploču krt i da lom jednog stupa/oslonca može dovesti do progresivnog i nenagoviještenog loma i na susjednim osloncima, jer pukotine i deformacije ostaju male sve do trenutka neposredno prije loma.
The use of shear reinforcement increases the punching capacity significantly, while also contributing to the increase in ductility and the possibility of redistribution of forces [12]. 
Korištenje armature za prihvat posmika značajno povećava nosivost na proboj uz povećanje duktilnosti i mogućnost redistribucije sila [12].
It is emphasized in the same paper that most models described in regulations and literature are related to empirical connections, and that they do not contribute to the understanding of phenomena, which is why their introduction into the analysis is more difficult. 
U istom radu je naglašeno da se većina modela u propisima i literaturi odnosi na empirijske veze i da ne pridonose razumijevanju fenomena pa je njihovo uvođenje u analizu otežano.
The theory of plasticity, fracture mechanics, and nonlinear finite element method, are increasingly used in theoretical analyses. 
U teorijskim analizama sve više se primjenjuje teorija plastičnosti, mehanika loma i nelinearna metoda konačnih elemenata (MKE).
The absence of properly developed theories that would explain behaviour of reinforced concrete slabs has lead to practical use of models contained in various technical regulations. 
Zbog nedostatka razvijene teorije kojom bi se objasnilo ponašanje armiranih ploča, u praksi se primjenjuju modeli iz različitih tehničkih propisa.
In Switzerland, the shear reinforcement is calculated on the basis of the theory of plasticity, according to SIA 262. 
U Švicarskoj se posmična armatura proračunava na bazi teorije plastičnosti prema normi SIA 262.
At that, rough approximations are made, and the contribution of concrete to punching capacity is neglected, which leads to conservative calculation results for shear reinforcement. 
Pri tome se čine gruba pojednostavljenja, zanemarujući doprinos betona nosivosti na posmik, što vodi konzervativnim rezultatima proračuna posmične armature.
Generally, technical regulations do not distinguish between punching through floor slabs and punching through foundation slabs. 
U tehničkim propisima se uglavnom ne pravi razlika između proboja stupa kroz strop i kroz ploču temelja.
The comprehensive monograph fib 12 [13] also places a high emphasis on the problem of column 
I u opsežnoj monografiji fib 12 [13] pretežno je razmatran problem proboja stupa kroz ploču kod stropova.
Punching of column footings - comparison of experimental and calculation results 
Banka podataka sadrži pokuse za ploče s armaturom i bez armature za posmik.
The application of this theory to the punching of slabs with transverse reinforcement is presented in [16]. 
Primjena ove teorije na proboj ploče s poprečnom armaturom prikazana je u radu [16].
In the draft of the new fib Model Code 2010 [17], provisions for the punching-related slab design point to the above-mentioned CSCT formulated by A. Muttoni, and also to papers [14] and [16]. 
U fib draft novog modela Code fib 2010 [17] odredbe za projektiranje ploča na proboj upućuju na prije spomenutu TKSP, na engleskom (CSCT), koju je formulirao A. Muttoni, i na radove [14 i 16].
This is regulated in the draft [17] by provisions contained in section 7.3.5. 
To je u draftu [17] navedeno u poglavlju
In order to test some regulations and their applicability to the punching resistance calculation of column footings, an experimental program was conducted in the scope of paper [18]. 
Da bi se ispitali pojedini propisi i njihova primjenljivost na proračun posmične otpornosti ploče temelja samca, u okviru rada [18] realiziran je eksperimentalni program.
The program of experimental investigations was made with goals that have also been set by some other researchers [3]. 
Program eksperimentalnih istraživanja sastavljen je s ciljem koji su postavili i neki drugi istraživači [3].
The column footing punching behaviour was studied so as to obtain answers to the following questions: how does the soil pressure distribution at the base of the footing affect the punching bearing capacity, and what is the difference in behaviour between floor slabs and foundation slabs in terms of column punching through the slab? 
Proučavano je ponašanje temelja na proboj radi dobivanja odgovora o tome kako utječe raspodjela pritisaka tla u dnu temelja na kapacitet nosivosti na proboj i kakva je razlika ponašanja međukatnih i temeljnih ploča iz aspekta proboja stupa kroz ploču.
During the tests, punching mechanisms have also been registered, especially the angles at which shear cracks are formed. 
Tijekom ispitivanja registrirani su i mehanizmi loma, naročito kutovi pod kojima se formiraju posmične pukotine.
The above overview points to the need for comparative analysis of experimental results and provisions contained in appropriate regulations. 
Prethodno prikazani pregled upućuje na potrebu uspoređivanja odredbi pojedinih propisa međusobno i s eksperimentalnim rezultatima.
The comparative analysis comprises the following documents: Byelaw BAB 87 (Byelaw on technical standards for concrete and reinforced concrete ) which was until recently used in a number of countries of our region, and which was implemented on a large number of projects; American ACI 318-02 [22]; British BS 110-1-1997 [20]; German DIN 1045-1 [21]; European EN 1992 EC-2 [22], and Russian regulations SNiP-84 [23]. 
Usporednom analizom obuhvaćeni su: Pravilnik BAB 87, koji je donedavno primjenjivan u zemljama regije i prema njemu je realiziran velik broj građevina; američki ACI 318-02 [22]; britanski BS 110-1-1997 [20]; njemački DIN 1045-1 [21]; europske EN 1992EC 2 [22] i ruski propisi SNiP-84 [23].
A modified model based on the Model Code (fib) [24] and EN 1992-1: 2004, and also on the European Concrete Platform from 2010 [25], is proposed in this paper. 
U ovom radu predložen je modificirani model zasnovan na Model Code (fib) [24] i EN 1992-1: 2004 te na Platformi iz 2010. godine [25].
The above regulations were compared based on the results obtained by experimental testing of the column footings punching on a gravel bedding. 
Međusobna usporedba navedenih propisa provedena je na osnovi rezultata eksperimentalnih ispitivanja pri probijanju temelja samaca na podlozi od šljunka.
The punching failure of the column footing supported by gravel was recorded by varying the slab height: 10; 12.5; 15.0; 17.5; 20.0 and 25.0 cm. 
Lom posmikom temeljne ploče oslonjene na šljunak registriran je uz variranje visine ploče od 10;12.5; 15.0; 17.5; 20.0 i 25.0 cm.
2. Comparative review of some experiments 
2. Pregled provedenih eksperimenata
According to published data, a relatively small number of punching tests for column footings resting on a real bedding has been realized since the start of the twentieth century [18]. 
Prema objavljenim podacima od početka dvadesetog stoljeća do danas realiziran je relativno mali broj ispitivanja proboja na temeljima koji su bili oslonjeni na realnu podlogu [18].
The tests carried out by Dieterle and Rostasy, Kordina and Nölting, and Dieterle and Steinle, cited in [3], are also quite significant. 
Ispitivanje proboja temelja na realnom tlu praktično su proveli jedino Hegger i ostali [3-4] - u sanduku pijeska i Rivkin [27] - na glini in situ.
The data about geometric characteristics, the number of tested footings, and supports used, are clearly arranged and presented in Table 1. 
Obuhvaćeni su propisi ACI (1983), BS (1985), CEB-FIP (1990), prEN (1991) i dva japanska propisa: prvi je Architectural Institute of Japan (AIJ), a drugi Japan Society of CE (JSCE).
Type of support 
Način oslanjanja
Number of tested footings 
Broj ispitanih temelja
Geometry of footing 
Geometrija temelja
Shape 
oblik
Dimension [mm] 
dimenzije [mm]
Effective depth [mm] 
statička visina [mm]
Hegger and Ricker 
Hegger i Ricker
Sand in the box 
sanduk s pijeskom
square 
kvadratni
Line 
linijsko
Line/Surface 
linijsko/površinsko
square and circular 
kvadratni i kružni
Dieterle and Rostasy 1987. 
Dieterle i Rostasy 1987.
Surface 
površinsko
Kordina and Nölting 1981. 
Kordina i Nölting 1981.
rectangular 
pravokutni
Dieterle and Steinle 1981. 
Dieterle i Steinle 1981.
Surface /clay and sand 
površinsko /glina i pijesak
650 and 1000 
650 i 1000
Spring 
opruge
(punching) 
(na proboj)
Overview of previous column-footing experiments 
Pregled dosadašnjih eksperimenata na temeljima
The analysis focused on more than 300 tests of reinforced concrete slabs. 
3. Pregled postupaka proračuna prema tehničkim propisima
A brief overview of the column-footing punching calculations, as given in some current technical regulations, is provided below. 
U većini je zastupljena poluempirijska metoda kritičnog presjeka pri proračunu nosivosti ploče odnosno temelja na proboj.
This cross-section is called a critical or control section, with the perimeter length u. 
Taj presjek se naziva kritični ili kontrolni presjek duljine opsega - u.
Based on this, the punching calculation is reduced to the control of shear stress in the critical section, i.e. the calculated shear stress in critical cross section tcal, at some distance from column edges, is compared with the punching shear stress v. If the requirement tcal<v, is fulfilled there is no danger of punching. 
Na osnovi toga se proračun proboja svodi samo na kontrolu posmičnog naprezanja u kritičnom presjeku, odnosno uspoređuje se računsko posmično naprezanje u kritičnom presjeku trač, na određenoj udaljenosti od ruba stupa, s graničnim posmičnim naprezanjem pri proboju v. Ako je ispunjen uvjet trač<v, nema opasnosti od proboja,
Otherwise, the shear reinforcement should be introduced to prevent punching. 
dok u suprotnom treba uvesti armaturu za osiguranje od proboja.
For column footing, the shear stress at punching is calculated in the critical section tcal according to 
Za temelje se računsko posmično naprezanje u kritičnom presjeku pri proboju trač računa prema izrazu:
τcal = 
τrač =
Okp - perimeter of critical (control) section d - effective cross section depth (mean value of two 
Okp - opseg kritičnog (kontrolnog) presjeka, d - statička (efektivna) visina presjeka (srednja vrijednost u
perpendicular directions). 
dva okomita pravca).
According to regulations, the normal ultimate force in column Pu can be reduced for the part of the soil reaction beneath the punching body based on the following expression 
Propisi dopuštaju da se granična normalna sila u stupu Pu reducira za dio reakcije tla ispod tijela proboja prema izrazu:
dead weight of the footing), 
A0 - površina baze tijela proboja u ravnini armature.
γc - material resistance factor for concrete 
γc - parcij. koefic. sigurnosti za beton
αs = 40 for interior column αs = 30 for edge column αs = 20 for corner column 
αs = 40 za unutrašnje stupove αs = 30 za rubne stupove αs = 20 za ugaone stupove
γm - partial safety factor ρs - flexural reinforcement ratio fcu - characteristic concrete cube compres 
γm - parcijalni koeficijent sigurnosti ρs - postotak armiranja fcu - karakteristična tlačna čvrstoća betona
sive strength 
dobivena ispitivanjem kocke
α - coefficient of concrete characteristics (1.0 for 
Rbl.um.d
bases of the punching pyramid/cone um = 2(bc+lc+2d) bc, lc - column dimensions at the basis 
proboja um = 2(bc+lc+2d) bc, lc - dimenzije stupa u osnovici
Rd ct 
vlačnih napona
c l 
Rd ct
ck 
c l
ρ 
ck
d - effective depth of footing; fc - characteristic compressive strength of concrete cylinder; b - perimeter of critical section 
d - efektivna (statička) visina temelja; fc - karakteristična tlačna čvrstoća betona dobivena ispitivanjem valjka; b - opseg kontrolnog presjeka
Ultimate shear stress calculation methods according to various regulations 
Postupci proračuna graničnog posmičnog naprezanja pri proboju v prema različitim propisima
Regulations for calculating ultimate shear stress at punching in the control section are very varied, as illustrated in Table 1. 
Za usporednu analizu u obzir su uzeti svi kontrolni presjeci iz pojedinih propisa.
Control sections from different regulations are used for comparative analysis. 
Izrazi (3) do (8) upisani su u tablicu 2.
4. Experimental studies 
4. Provedena eksperimentalna istraživanja
The schematic of the experimental setup consisting of the test frame, test specimen - column footing, hydraulic jack, and prepared sub-grade is shown in Figure 2. 
Shema konstrukcijskog sklopa za provođenje eksperimenta koji čine ispitni okvir, pokusno tijelo - temelj samac, hidraulična preša i pripremljeno tlo prikazana je na slici 2.
Experiments were conducted in 2009. 
Eksperimentalna ispitivanja su provedena tijekom 2009. godine.
Section of the experimental setup 
Shematski prikaz eksperimenta
Experimental testing in situ 
Eksperimentalno ispitivanje in situ
Dimensions and reinforcement of some footings 
Dimenzije i armiranje jednog od ispitivanih temelja
Particle size distribution of gravel 
Krivulja granulometrijskog sastava šljunka
The compaction level is controlled for each layer by the circular plate test. 
Zbijenost svakog sloja je kontrolirana pokusom kružne ploče.
The control section in some regulations, as dependent on the effective footing depth d 
Kontrolni presjek prema pojedinim propisima u ovisnosti o efektivnoj visini temelja d
The truss structure of the frame, as well as its dimensions, enable an undisturbed formation of sliding surfaces in the soil beneath the foundations in case the soil failure should precede the punching shear in the course of the loading. 
Konstrukcija okvira kao i njegove dimenzije omogućavale su nesmetano formiranje kliznih površina u tlu ispod temelja ako bi pri opterećivanju prije došlo do loma tla nego proboja temelja.
This setup allows footings testing under completely realistic boundary conditions in terms of soil, as well as proper comparison and verification of earlier laboratory testing results with in situ tests. 
Time je bilo omogućeno ispitivanje temelja u realnim graničnim uvjetima u pogledu tla te uspoređivanje i vrednovanje prijašnjih rezultata ispitivanja u laboratoriju s ispitivanjima in situ.
The adopted footing dimensions are 85x85cm in plan, and they correspond to experiments made by Kinnunen and Hegger et al. [4], with regard to result comparison possibilities, and also according to the capacity of the available measuring equipment (approximately 1000 kN). 
Usvojene dimenzije temelja su 85x85 cm u tlocrtu i odgovaraju eksperimentima Kinnunena i Heggera, i dr. [4] radi uspoređivanja rezultata, a također i zato jer odgovaraju kapacitetu raspoložive mjerne opreme (približno 1000 kN).
The dimensions and characteristics of the footing are given in Table 3. and shown in Figure 4. 
Dimenzije i karakteristike temelja prikazane su u tablici 3. i na slici 4.
Steel bars 8 mm in diameter were used for the reinforcement of the footings, and the percentage of reinforcement amounted to approximately 0.4 % for all footings. 
Za armiranje temelja je korištena armatura promjera 8 mm, a postotak armiranja je iznosio približno 0.4 % za sve temelje.
Reinforcing steel characteristics were determined on three samples of the reinforcement used in the testing. 
Karakteristike upotrijebljenog čelika utvrđene su na tri uzorka korištene armature.
The obtained mean values were: tensile strength fsu = 653 MPa, yield point fsy = 570 MPa, and the corresponding yield strain ε ≈ 2,7 ‰. 
Dobivene srednje vrijednosti su iznosile: vlačna čvrstoća - 653 MPa, granica tečenja - 570 MPa i odgovarajuća dilatacija tečenja približno 2.7 ‰.
The experimental testing was conducted by placing the footing on the soil surface and by loading it with a vertical centric force, which was applied by a hydraulic jack positioned between the steel cross-beam and the footings (Figure 3). 
Eksperimentalno ispitivanje je provedeno tako što su temeljne stope postavljene na površinu tla i opterećivane vertikalnom centričnom silom koja se aplicira hidrauličnom prešom smještenom između poprečne grede i temelja (slika 3).