From the second Lula mandate applies in Brazil "Programa de Aceleração do Crescimento"(PAC), which created across the country several construction's large projects.Among the main were buildings of UHE Jirau, Santo Antonio in Rondônia and Belo Monte in Pará. These buildings were marked by strikes of workers that executed, mainly in the years 2011 and 2012, and these were characterized by occur outside the official union, spontaneously, and resort to a violent repertoire, with breaks and fire machines and structures of construction sites. Thus, throughout this research we aim to understand how these processes occurred and what motivated the workers to mobilize the way they did. For this, we turn to an approximation effort theoretical tools provided by Political Process Theory, by Sidney Tarrow, and the "classic" marxist production with the intent to understand these events. For this, we seek to profile the work of these buildings, which we call "peões-de-trecho", and the conditions that influence the decision on the outbreak of the strike process, we discussed the factory regimes which they are submitted, and the economic scenario and the union faced by them to mobilize. In addition, we held a debate about the influence of the Brazilian union structure of these workers, which we understand as a "Sindicalismo de Estado". From this, we discuss the repertoire that is adopted by these workers, the causes and consequences of using violent tactics. Finally, we realize that due to the open economic scenario by the PAC with several works the country and the maintenance of working conditions, wages and living in construction sites, not remaining alternatives to workers than mobilization. However, due to union structure and the presence of trade unions completely away from the workers, they were forced to completely organize the default of the official trade union leadership, which, coupled with the absence of individuals with previous experience in movements led them to adopt a repertoire spontaneous, and sometimes resort to violence. We also realize that these workers reached a satisfactory economic balance, however, the organizational-political field yet to realize a fundamental transformation. But the very act of making strikes on these conditions is already a great victory.