Cement is fast losing its strength and profits are shrinking and its makers are now focussing on ready-mix concrete (RMC) to push up sinking margins. After Lafarge took over the mantle of industry leader buying out Larsen & Toubro's RMC business, it is global rival Holcim's turn to strike as it combines the concrete power of its two local associates Ambuja Cements and ACC to build on the lucrative RMC business.